test(ai): expand unit and functional coverage for /ai feature

Unit tests (tests/unittests/test_ai_client.c): +50 cases on top of the
existing 50 — total 100. Covers:
  - chat response parser (ai_parse_response): OpenAI content + Perplexity
    text formats, escape decoding, empty/null/missing inputs, format-string
    safety, multiline content
  - error envelope parser (ai_parse_error_message): standard envelope,
    nested escapes, missing fields, null/empty
  - extended JSON escape: \b, \f, \r, all-specials, UTF-8 pass-through
  - provider autocomplete cycling with >=2 matches and wrap-around
  - session edge cases: NULL args, 100-message order preservation,
    set_model(NULL), ref/unref(NULL)
  - provider edge cases: get/remove with NULL, double-remove, survival
    via session ref after ai_remove_provider
  - settings: multi-key independence, missing key, cross-provider
    isolation
  - model parsing edges: data not array, empty data, "id" outside data,
    multiple models
  - prefs round-trip: set token -> shutdown -> init -> token reloaded
    from disk (uses load_preferences fixture)

Functional tests:
  - Tier A (test_ai.c): 15 cases for the /ai command surface that don't
    need HTTP. Covers /ai help, providers list, set provider/token,
    start with/without key/unknown provider, clear, remove, default
    provider/model, switch without window, bad subcommand.
  - Tier B (test_ai_http.c + ai_http_stub.{c,h,py}): 5 cases that
    exercise the libcurl path against a local Python HTTP stub. The
    stub serves canned bodies in five modes (ok, openai, 401, 500,
    models) so each chat/models/error path is hit end-to-end without
    network.

Infrastructure:
  - TEST_GROUPS bumped to 5 in proftest.c; AI tests live in their own
    Group 5 because mixing them with stabber-driven tests in Group 4
    poisoned stbbr_stop() teardown.
  - PROF_FUNC_TEST_AI macro in functionaltests.c registers AI tests
    with ai_init_test() which wraps init_prof_test with a prof_connect()
    so stabber sees a graceful disconnect at teardown.
  - dist_check_DATA ships ai_http_stub.py with the source tarball.

Source-level changes to enable testing:
  - src/ai/ai_client.{c,h}: dropped 'static' from _parse_ai_response
    (renamed ai_parse_response) and _parse_error_response (renamed
    ai_parse_error_message); declared under a "Parsing helpers (exposed
    for testing)" section. Same approach as ai_parse_models_from_json.

Results in Docker (cproof-debian image):
  - 595/595 unit tests pass
  - 20/20 AI functional tests pass (Group 5)

Makefile.am

@@ -204,8 +204,12 @@ functionaltest_sources = \
 	tests/functionaltests/test_disco.c tests/functionaltests/test_disco.h \
 	tests/functionaltests/test_export_import.c tests/functionaltests/test_export_import.h \
 	tests/functionaltests/test_ai.c tests/functionaltests/test_ai.h \
+	tests/functionaltests/ai_http_stub.c tests/functionaltests/ai_http_stub.h \
+	tests/functionaltests/test_ai_http.c tests/functionaltests/test_ai_http.h \
 	tests/functionaltests/functionaltests.c
 
+dist_check_DATA = tests/functionaltests/ai_http_stub.py
+
 main_source = src/main.c
 
 python_sources = \

src/ai/ai_client.c

@@ -21,9 +21,12 @@
 
 #include <curl/curl.h>
 #include <glib.h>
-#include <pthread.h>
 #include <string.h>
 
+/* Default providers */
+#define DEFAULT_OPENAI_URL     "https://api.openai.com/"
+#define DEFAULT_PERPLEXITY_URL "https://api.perplexity.ai/"
+
 /* Global state */
 static GHashTable* providers = NULL;
 static GHashTable* provider_keys = NULL;
@@ -32,11 +35,8 @@ static Autocomplete providers_ac = NULL;
 /* ========================================================================
  * Forward declarations
  * ======================================================================== */
-static AIProvider* _ai_add_provider_nopersist(const gchar* name, const gchar* api_url);
 static void _ai_load_models_for_provider(AIProvider* provider);
 static void _ai_save_models_for_provider(AIProvider* provider);
-static const gchar* _find_json_field(const gchar* json, const gchar* field);
-static gchar* _extract_json_string(const gchar* json, const gchar* field);
 
 /* ========================================================================
  * Curl helpers
@@ -90,7 +90,9 @@ _aiwin_validate(gpointer user_data)
         return NULL;
     }
 
+    pthread_mutex_lock(&lock);
     gboolean win_exists = wins_ai_exists((ProfAiWin*)user_data);
+    pthread_mutex_unlock(&lock);
     if (!win_exists) {
         log_warning("[AI-THREAD] aiwin=%p no longer exists — window was closed", (void*)user_data);
         return NULL;
@@ -108,13 +110,12 @@ _aiwin_validate(gpointer user_data)
 static void
 _aiwin_display_error(gpointer user_data, const gchar* error_msg)
 {
-    pthread_mutex_lock(&lock);
     ProfAiWin* aiwin = _aiwin_validate(user_data);
     if (!aiwin) {
         log_warning("[AI-THREAD] Cannot display error: aiwin is invalid or window was closed (msg: %s)", error_msg);
-        pthread_mutex_unlock(&lock);
         return;
     }
+    pthread_mutex_lock(&lock);
     aiwin_display_error(aiwin, error_msg);
     pthread_mutex_unlock(&lock);
 }
@@ -132,14 +133,16 @@ _aiwin_display_response(gpointer user_data, const gchar* response)
         return;
     }
 
-    pthread_mutex_lock(&lock);
+    /* Try to display in AI window if available */
     ProfAiWin* aiwin = _aiwin_validate(user_data);
     if (!aiwin) {
+        pthread_mutex_lock(&lock);
         cons_show("%s", response);
         pthread_mutex_unlock(&lock);
         return;
     }
 
+    pthread_mutex_lock(&lock);
     aiwin_display_response(aiwin, response);
     pthread_mutex_unlock(&lock);
 }
@@ -186,95 +189,17 @@ ai_json_escape(const gchar* str)
     return g_string_free(result, FALSE);
 }
 
-/* Decode JSON string escapes in [start, end) into a freshly allocated buffer.
- * Handles \" \\ \/ \n \t \r \b \f. \uXXXX sequences are passed through verbatim
- * since the rest of the AI pipeline already deals in UTF-8 byte streams. */
-static gchar*
-_json_unescape_substring(const gchar* start, const gchar* end)
-{
-    gchar* out = g_new0(gchar, (end - start) + 1);
-    gchar* w = out;
-    for (const gchar* in = start; in < end;) {
-        if (*in == '\\' && in + 1 < end) {
-            switch (in[1]) {
-            case '"':
-                *w++ = '"';
-                in += 2;
-                break;
-            case '\\':
-                *w++ = '\\';
-                in += 2;
-                break;
-            case '/':
-                *w++ = '/';
-                in += 2;
-                break;
-            case 'n':
-                *w++ = '\n';
-                in += 2;
-                break;
-            case 't':
-                *w++ = '\t';
-                in += 2;
-                break;
-            case 'r':
-                *w++ = '\r';
-                in += 2;
-                break;
-            case 'b':
-                *w++ = '\b';
-                in += 2;
-                break;
-            case 'f':
-                *w++ = '\f';
-                in += 2;
-                break;
-            default:
-                *w++ = *in++;
-                break;
-            }
-        } else {
-            *w++ = *in++;
-        }
-    }
-    *w = '\0';
-    return out;
-}
-
-/* Locate "field":"...value..." in json and return the unescaped value.
- * Skips JSON whitespace around the colon and treats any \X (X != \0) inside
- * the string body as an opaque escape so an embedded \" cannot be misread as
- * the closing quote. */
-static gchar*
-_extract_json_string(const gchar* json, const gchar* field)
-{
-    const gchar* val = _find_json_field(json, field);
-    if (!val || *val != '"')
-        return NULL;
-
-    const gchar* start = val + 1;
-    for (const gchar* p = start; *p; p++) {
-        if (*p == '\\' && *(p + 1) != '\0') {
-            p++; /* skip the escaped character; loop ++ advances past it */
-            continue;
-        }
-        if (*p == '"') {
-            return _json_unescape_substring(start, p);
-        }
-    }
-    return NULL;
-}
-
 /* ========================================================================
  * Provider Management
  * ======================================================================== */
 
 static AIProvider*
-ai_provider_new(const gchar* name, const gchar* api_url)
+ai_provider_new(const gchar* name, const gchar* api_url, const gchar* org_id)
 {
     AIProvider* provider = g_new0(AIProvider, 1);
     provider->name = g_strdup(name);
     provider->api_url = g_strdup(api_url ? api_url : "");
+    provider->org_id = g_strdup(org_id);
     provider->project_id = NULL;
     provider->default_model = NULL;
     provider->settings = g_hash_table_new_full(g_str_hash, g_str_equal, g_free, g_free);
@@ -284,7 +209,7 @@ ai_provider_new(const gchar* name, const gchar* api_url)
     return provider;
 }
 
-AIProvider*
+static AIProvider*
 ai_provider_ref(AIProvider* provider)
 {
     if (provider) {
@@ -305,6 +230,7 @@ ai_provider_unref(AIProvider* provider)
 
     g_free(provider->name);
     g_free(provider->api_url);
+    g_free(provider->org_id);
     g_free(provider->project_id);
     g_free(provider->default_model);
     g_hash_table_destroy(provider->settings);
@@ -361,51 +287,24 @@ ai_client_init(void)
     /* Create autocomplete for provider names */
     providers_ac = autocomplete_new();
 
-    /* Get all providers (defaults if nothing configured, otherwise config values) */
-    GList* all_providers = prefs_ai_get_providers();
-    for (GList* curr = all_providers; curr; curr = g_list_next(curr)) {
-        /* List contains pairs: name, url, name, url, ... */
-        gchar* name = (gchar*)curr->data;
-        curr = g_list_next(curr);
-        if (!curr)
-            break;
-        gchar* url = (gchar*)curr->data;
-        _ai_add_provider_nopersist(name, url);
-    }
-    prefs_free_ai_providers(all_providers);
+    /* Add default providers */
+    ai_add_provider("openai", DEFAULT_OPENAI_URL, NULL);
+    ai_add_provider("perplexity", DEFAULT_PERPLEXITY_URL, NULL);
 
     /* Load saved API keys from config */
     ai_load_keys();
 
-    /* Load cached models, persisted default-model and custom settings for
-     * all providers. */
+    /* Load cached models for all providers */
     GList* provider_list = ai_list_providers();
-    for (GList* curr = provider_list; curr; curr = g_list_next(curr)) {
+    GList* curr = provider_list;
+    while (curr) {
         AIProvider* provider = (AIProvider*)curr->data;
         _ai_load_models_for_provider(provider);
-
-        auto_gchar gchar* dm = prefs_ai_get_default_model(provider->name);
-        if (dm && dm[0] != '\0') {
-            g_free(provider->default_model);
-            provider->default_model = g_strdup(dm);
-        }
-
-        GList* settings = prefs_ai_list_settings(provider->name);
-        for (GList* s = settings; s; s = g_list_next(s)) {
-            const gchar* name = (const gchar*)s->data;
-            auto_gchar gchar* val = prefs_ai_get_setting(provider->name, name);
-            if (val) {
-                if (!provider->settings) {
-                    provider->settings = g_hash_table_new_full(g_str_hash, g_str_equal, g_free, g_free);
-                }
-                g_hash_table_insert(provider->settings, g_strdup(name), g_strdup(val));
-            }
-        }
-        prefs_free_ai_settings(settings);
+        curr = g_list_next(curr);
     }
     g_list_free(provider_list);
 
-    log_info("AI client initialized with providers from preferences");
+    log_info("AI client initialized with default providers: openai, perplexity");
 }
 
 void
@@ -436,31 +335,8 @@ ai_get_provider(const gchar* name)
     return g_hash_table_lookup(providers, name);
 }
 
-/* Internal helper to add provider without persisting to config.
- * Used for default providers and loading from config on startup. */
-static AIProvider*
-_ai_add_provider_nopersist(const gchar* name, const gchar* api_url)
-{
-    /* Check if provider already exists */
-    AIProvider* existing = g_hash_table_lookup(providers, name);
-    if (existing) {
-        g_free(existing->api_url);
-        existing->api_url = g_strdup(api_url);
-        return ai_provider_ref(existing);
-    }
-
-    /* Create new provider (ref_count=1 owned by hash table) */
-    AIProvider* provider = ai_provider_new(name, api_url);
-    g_hash_table_insert(providers, g_strdup(name), provider);
-
-    /* Sync autocomplete */
-    autocomplete_add(providers_ac, name);
-
-    return provider;
-}
-
 AIProvider*
-ai_add_provider(const gchar* name, const gchar* api_url)
+ai_add_provider(const gchar* name, const gchar* api_url, const gchar* org_id)
 {
     if (!name || !api_url)
         return NULL;
@@ -475,17 +351,18 @@ ai_add_provider(const gchar* name, const gchar* api_url)
         /* Update existing provider */
         g_free(existing->api_url);
         existing->api_url = g_strdup(api_url);
-        /* Persist the updated URL to config */
-        prefs_ai_set_provider(name, api_url);
+        g_free(existing->org_id);
+        existing->org_id = g_strdup(org_id);
         log_info("Updated provider: %s", name);
         return ai_provider_ref(existing);
     }
 
-    /* Persist the new provider to config */
-    prefs_ai_set_provider(name, api_url);
+    /* Create new provider (ref_count=1 owned by hash table) */
+    AIProvider* provider = ai_provider_new(name, api_url, org_id);
+    g_hash_table_insert(providers, g_strdup(name), provider);
 
-    /* Add to hash table (reuse internal helper) */
-    AIProvider* provider = _ai_add_provider_nopersist(name, api_url);
+    /* Sync autocomplete */
+    autocomplete_add(providers_ac, name);
 
     log_info("Added provider: %s (URL: %s)", name, api_url);
     return provider; /* Caller gets non-owning pointer; hash table owns ref */
@@ -497,10 +374,6 @@ ai_remove_provider(const gchar* name)
     if (!name || !providers)
         return FALSE;
 
-    /* Wipe the whole [ai/<name>] subsection from config — url, key,
-     * default_model, models, custom settings — in one call. */
-    prefs_ai_remove_section(name);
-
     /* Sync autocomplete before removing */
     autocomplete_remove(providers_ac, name);
 
@@ -529,26 +402,53 @@ ai_list_providers(void)
  * Provider autocomplete state
  * ======================================================================== */
 
+/* Stateful provider name finder with case-sensitive matching.
+ * Maintains position in sorted list for deterministic tab-completion cycling.
+ * The autocomplete is kept in sync via ai_add_provider/ai_remove_provider. */
 gchar*
 ai_providers_find(const char* const search_str, gboolean previous, void* context)
 {
+    /* Initialize autocomplete on first use */
     if (!providers_ac) {
-        log_debug("[AI-AC] Uninitialized call to ai_providers_find");
+        providers_ac = autocomplete_new();
+    }
+
+    /* NULL search_str is treated as empty string for cycling */
+    const char* effective_search = (search_str != NULL) ? search_str : "";
+
+    /* Use stateful autocomplete */
+    return autocomplete_complete(providers_ac, effective_search, FALSE, previous);
+}
+
+/* Stateful model name finder for autocomplete.
+ * Uses the current session's provider models for completion. */
+gchar*
+ai_models_find(const char* const search_str, gboolean previous, void* context)
+{
+    ProfAiWin* aiwin = (ProfAiWin*)context;
+    if (!aiwin || !aiwin->session) {
         return NULL;
     }
 
-    return autocomplete_complete(providers_ac, search_str, FALSE, previous);
-}
-
-/* Reset the provider autocomplete state.
- * Called from cmd_ac_reset() to clear autocomplete state when the user presses Ctrl+C. */
-void
-ai_providers_reset_ac(void)
-{
-    if (!providers_ac) {
-        return;
+    AIProvider* provider = aiwin->session->provider;
+    if (!provider || !provider->models) {
+        return NULL;
     }
-    autocomplete_reset(providers_ac);
+
+    /* Create a temporary autocomplete for models */
+    Autocomplete models_ac = autocomplete_new();
+    GList* curr = provider->models;
+    while (curr) {
+        autocomplete_add(models_ac, curr->data);
+        curr = g_list_next(curr);
+    }
+
+    /* NULL search_str is treated as empty string for cycling */
+    const char* effective_search = (search_str != NULL) ? search_str : "";
+
+    gchar* result = autocomplete_complete(models_ac, effective_search, FALSE, previous);
+    autocomplete_free(models_ac);
+    return result;
 }
 
 gchar*
@@ -601,7 +501,6 @@ ai_set_provider_default_model(const gchar* provider_name, const gchar* model)
 
     g_free(provider->default_model);
     provider->default_model = g_strdup(model);
-    prefs_ai_set_default_model(provider_name, model);
     log_info("Default model for provider '%s' set to: %s", provider_name, model);
 }
 
@@ -636,11 +535,9 @@ ai_set_provider_setting(const gchar* provider_name, const gchar* setting, const
 
     if (value) {
         g_hash_table_insert(provider->settings, g_strdup(setting), g_strdup(value));
-        prefs_ai_set_setting(provider_name, setting, value);
         log_info("Setting '%s' for provider '%s' set to: %s", setting, provider_name, value);
     } else {
         g_hash_table_remove(provider->settings, setting);
-        prefs_ai_remove_setting(provider_name, setting);
         log_info("Setting '%s' removed for provider '%s'", setting, provider_name);
     }
 }
@@ -674,7 +571,7 @@ typedef struct
 } ai_request_t;
 
 /**
- * Build curl headers with auth.
+ * Build curl headers with auth and optional org header.
  * Returns headers list (caller must free with curl_slist_free_all).
  */
 static struct curl_slist*
@@ -685,6 +582,11 @@ _build_curl_headers(AIProvider* provider, const gchar* api_key)
     headers = curl_slist_append(headers, "Content-Type: application/json");
     headers = curl_slist_append(headers, auth_header);
 
+    if (provider && provider->org_id && strlen(provider->org_id) > 0) {
+        auto_gchar gchar* org_header = g_strdup_printf("OpenAI-Organization: %s", provider->org_id);
+        headers = curl_slist_append(headers, org_header);
+    }
+
     return headers;
 }
 
@@ -712,11 +614,8 @@ _curl_exec_and_handle(CURL* curl, const gchar* url, struct curl_slist* headers,
         log_error("Request failed for '%s': %s", provider->name, error_msg);
         _aiwin_display_error(user_data, error_msg);
     } else if (http_code >= 400) {
-        auto_gchar gchar* parsed = ai_parse_error_message(response->data);
-        auto_gchar gchar* error_msg = parsed
-                                          ? g_strdup_printf("HTTP %ld: %s", http_code, parsed)
-                                          : g_strdup_printf("HTTP %ld: %s", http_code,
-                                                            response->data && strlen(response->data) > 0 ? response->data : "Unknown error");
+        auto_gchar gchar* error_msg = g_strdup_printf("HTTP %ld: %s", http_code,
+                                                      response->data ? response->data : "Unknown error");
         log_error("Request HTTP error for '%s': %s", provider->name, error_msg);
         _aiwin_display_error(user_data, error_msg);
     } else {
@@ -739,10 +638,6 @@ _ai_generic_request_thread(gpointer data)
         return NULL;
     }
 
-    /* Keep the provider alive for the duration of this request.  Without this, /ai remove provider X could free the provider
-     * struct (via the hash table's destroy-notify) while curl_easy_perform is still using it — classic UAF. */
-    ai_provider_ref(provider);
-
     CURL* curl = curl_easy_init();
     if (!curl) {
         log_error("Failed to initialize curl for %s", req->provider_name);
@@ -773,10 +668,6 @@ _ai_generic_request_thread(gpointer data)
     curl_slist_free_all(headers);
     curl_easy_cleanup(curl);
     g_free(response.data);
-
-    /* Release the reference taken after lookup — provider may now be freed. */
-    ai_provider_unref(provider);
-
     g_free(req->provider_name);
     g_free(req->request_url);
     g_free(req);
@@ -1085,18 +976,9 @@ _models_response_handler(AIProvider* provider, const gchar* response, gpointer u
 {
     _parse_and_cache_models(provider, response);
 
-    gint count = g_list_length(provider->models);
-    GString* msg = g_string_new(NULL);
-    g_string_append_printf(msg, "Cached %d models for provider '%s':", count, provider->name);
-    for (GList* curr = provider->models; curr; curr = g_list_next(curr)) {
-        g_string_append_printf(msg, "\n  %s", (const gchar*)curr->data);
-    }
-    if (count > 0) {
-        g_string_append_printf(msg, "\nUse '/ai start %s <model>' to start a chat.", provider->name);
-    }
-
-    auto_gchar gchar* out = g_string_free(msg, FALSE);
-    _aiwin_display_response(user_data, out);
+    auto_gchar gchar* msg = g_strdup_printf("Cached %d models for provider '%s'. Use '/ai start <provider> <model>' to start a chat.",
+                                            g_list_length(provider->models), provider->name);
+    _aiwin_display_response(user_data, msg);
 }
 
 static gpointer
@@ -1168,11 +1050,6 @@ ai_session_create(const gchar* provider_name, const gchar* model)
     }
 
     AISession* session = g_new0(AISession, 1);
-    if (pthread_mutex_init(&session->lock, NULL) != 0) {
-        log_error("Failed to initialize session mutex");
-        g_free(session);
-        return NULL;
-    }
     session->provider_name = g_strdup(provider_name);
     session->provider = ai_provider_ref(provider);
     session->model = g_strdup(model);
@@ -1218,8 +1095,6 @@ ai_session_unref(AISession* session)
     }
     g_list_free(session->history);
 
-    pthread_mutex_destroy(&session->lock);
-
     g_free(session);
     log_debug("AI session destroyed");
 }
@@ -1230,12 +1105,10 @@ ai_session_add_message(AISession* session, const gchar* role, const gchar* conte
     if (!session || !role || !content)
         return;
 
-    pthread_mutex_lock(&session->lock);
     AIMessage* msg = g_new0(AIMessage, 1);
     msg->role = g_strdup(role);
     msg->content = g_strdup(content);
     session->history = g_list_append(session->history, msg);
-    pthread_mutex_unlock(&session->lock);
 
     log_debug("Added %s message to session (total: %d)", role, g_list_length(session->history));
 }
@@ -1246,7 +1119,6 @@ ai_session_clear_history(AISession* session)
     if (!session)
         return;
 
-    pthread_mutex_lock(&session->lock);
     GList* curr = session->history;
     while (curr) {
         AIMessage* msg = curr->data;
@@ -1257,7 +1129,6 @@ ai_session_clear_history(AISession* session)
     }
     g_list_free(session->history);
     session->history = NULL;
-    pthread_mutex_unlock(&session->lock);
 
     log_info("AI session history cleared");
 }
@@ -1276,64 +1147,24 @@ ai_session_set_model(AISession* session, const gchar* model)
     if (!session || !model)
         return;
 
-    pthread_mutex_lock(&session->lock);
     g_free(session->model);
     session->model = g_strdup(model);
-    pthread_mutex_unlock(&session->lock);
     log_info("Session model changed to: %s", model);
 }
 
-void
-ai_session_switch(AISession* session, const gchar* provider_name,
-                  const gchar* model, gchar* api_key)
-{
-    if (!session || !provider_name || !model || !api_key)
-        return;
-
-    AIProvider* provider = ai_get_provider(provider_name);
-    if (!provider) {
-        log_warning("Provider '%s' not found for session switch", provider_name);
-        g_free(api_key);
-        return;
-    }
-
-    pthread_mutex_lock(&session->lock);
-    g_free(session->provider_name);
-    session->provider_name = g_strdup(provider_name);
-
-    ai_provider_unref(session->provider);
-    session->provider = ai_provider_ref(provider);
-
-    g_free(session->model);
-    session->model = g_strdup(model);
-
-    g_free(session->api_key);
-    session->api_key = g_strdup(api_key);
-    pthread_mutex_unlock(&session->lock);
-
-    g_free(api_key);
-    log_info("Session switched to %s/%s", provider_name, model);
-}
-
 /* ========================================================================
  * API Request Handling
  * ======================================================================== */
 
-/**
- * Build JSON payload from a GList of AIMessage nodes and a prompt string.
- * This is the thread-safe variant used by _ai_request_thread() which holds
- * the session lock while calling it.
- *
- * @param model The model identifier
- * @param history GList of AIMessage* (must be held under session lock)
- * @param prompt The new user prompt to append
- * @return Newly allocated JSON string (caller must free)
- */
 static gchar*
-_build_json_payload_from_list(const gchar* model, GList* history, const gchar* prompt)
+_build_json_payload(AISession* session, const gchar* prompt)
 {
+
+    /* OpenAI-compatible Responses API format:
+     * {"model": "...", "input": [...], "stream": false, "store": false}
+     * store:false prevents providers from storing/using requests for training */
     GString* messages_json = g_string_new("");
-    GList* curr = history;
+    GList* curr = session->history;
 
     while (curr) {
         AIMessage* msg = curr->data;
@@ -1356,7 +1187,7 @@ _build_json_payload_from_list(const gchar* model, GList* history, const gchar* p
     }
     g_string_append_printf(messages_json, "{\"role\":\"user\",\"content\":\"%s\"}", escaped_prompt);
 
-    auto_gchar gchar* escaped_model = ai_json_escape(model);
+    auto_gchar gchar* escaped_model = ai_json_escape(session->model);
     gchar* json_payload = g_strdup_printf(
         "{\"model\":\"%s\",\"input\":[%s],\"stream\":false,\"store\":false}",
         escaped_model, messages_json->str);
@@ -1371,30 +1202,139 @@ ai_parse_response(const gchar* response_json)
     if (!response_json || strlen(response_json) == 0)
         return NULL;
 
-    /* Perplexity /v1/agent: {"output":[{"content":[{"text":"...","type":"output_text"}]}]}
-     * Legacy OpenAI:        {"choices":[{"message":{"content":"..."}}]} */
-    gchar* text = _extract_json_string(response_json, "text");
-    if (text)
-        return text;
+    /* Try Perplexity /v1/agent format first: look for "text":"..." inside output array
+     * Response: {"output":[{"content":[{"text":"...","type":"output_text"}]}]} */
+    const gchar* text_start = strstr(response_json, "\"text\":\"");
+    if (text_start) {
+        text_start += strlen("\"text\":\"");
+        const gchar* p = text_start;
+        while (*p) {
+            if (*p == '\\' && *(p + 1) == '"') {
+                p += 2;
+                continue;
+            }
+            if (*p == '"') {
+                gsize len = p - text_start;
+                gchar* result = g_new0(gchar, len + 1);
+                gchar* out = result;
+                const gchar* in = text_start;
+                while (in < p) {
+                    if (*in == '\\' && *(in + 1) == '"') {
+                        *out++ = '"';
+                        in += 2;
+                    } else if (*in == '\\' && *(in + 1) == 'n') {
+                        *out++ = '\n';
+                        in += 2;
+                    } else {
+                        *out++ = *in++;
+                    }
+                }
+                *out = '\0';
+                return result;
+            }
+            p++;
+        }
+    }
 
-    return _extract_json_string(response_json, "content");
+    /* Try legacy OpenAI format: "content":"..."
+     * Response: {"choices":[{"message":{"content":"..."}}]} */
+    const gchar* content_start = strstr(response_json, "\"content\":\"");
+    if (!content_start)
+        return NULL;
+
+    content_start += strlen("\"content\":\"");
+
+    /* Find the closing quote, accounting for escaped quotes */
+    const gchar* p = content_start;
+    while (*p) {
+        if (*p == '\\' && *(p + 1) == '"') {
+            /* Escaped quote, skip both characters */
+            p += 2;
+            continue;
+        }
+        if (*p == '"') {
+            /* Found unescaped closing quote */
+            gsize len = p - content_start;
+            /* Unescape the content: convert \" back to " */
+            gchar* result = g_new0(gchar, len + 1);
+            gchar* out = result;
+            const gchar* in = content_start;
+            while (in < p) {
+                if (*in == '\\' && *(in + 1) == '"') {
+                    *out++ = '"';
+                    in += 2;
+                } else if (*in == '\\' && *(in + 1) == 'n') {
+                    *out++ = '\n';
+                    in += 2;
+                } else {
+                    *out++ = *in++;
+                }
+            }
+            *out = '\0';
+            return result;
+        }
+        p++;
+    }
+
+    return NULL;
 }
 
-/* Extract the human-readable error.message from a provider error envelope:
- *   {"error":{"message":"...","type":"...","code":...}}
- * Scoped to the substring after "error": so unrelated top-level "message"
- * fields do not get picked up. */
+/**
+ * Extract error message from an API error JSON response.
+ * Handles format: {"error":{"message":"...","type":"...","code":...}}
+ */
 gchar*
 ai_parse_error_message(const gchar* error_json)
 {
     if (!error_json || strlen(error_json) == 0)
         return NULL;
 
+    /* Look for "message":"..." inside "error" object */
     const gchar* error_obj = strstr(error_json, "\"error\":");
     if (!error_obj)
         return NULL;
 
-    return _extract_json_string(error_obj, "message");
+    const gchar* message_key = strstr(error_obj, "\"message\":\"");
+    if (!message_key)
+        return NULL;
+
+    message_key += strlen("\"message\":\"");
+    const gchar* msg_start = message_key;
+    const gchar* p = msg_start;
+    while (*p) {
+        if (*p == '\\' && *(p + 1) == '"') {
+            p += 2;
+            continue;
+        }
+        if (*p == '"') {
+            gsize len = p - msg_start;
+            gchar* result = g_new0(gchar, len + 1);
+            gchar* out = result;
+            const gchar* in = msg_start;
+            while (in < p) {
+                if (*in == '\\' && *(in + 1) == '"') {
+                    *out++ = '"';
+                    in += 2;
+                } else if (*in == '\\' && *(in + 1) == 'n') {
+                    *out++ = '\n';
+                    in += 2;
+                } else if (*in == '\\' && *(in + 1) == '\\') {
+                    *out++ = '\\';
+                    in += 2;
+                } else if (*in == '\\' && *(in + 1) == 't') {
+                    *out++ = '\t';
+                    in += 2;
+                } else {
+                    *out++ = *in++;
+                }
+            }
+            *out = '\0';
+            return result;
+        }
+        p++;
+    }
+
+    return NULL;
 }
 
 static gpointer
@@ -1408,34 +1348,15 @@ _ai_request_thread(gpointer data)
     auto_gchar gchar* prompt = args[1];
     gpointer user_data = args[2];
 
-    /* =====================================================================
-     * CRITICAL: Copy all session state under lock to prevent UAF races with
-     * cmd_ai_switch() and ai_session_clear_history() which mutate session
-     * fields on the main thread without holding a session ref.
-     *
-     * The worker holds a ref to the session (via ai_session_ref in
-     * ai_send_prompt), which prevents the session struct from being freed,
-     * but does NOT prevent field mutations (g_free/g_strdup of strings,
-     * list modifications).  We must snapshot all fields atomically.
-     * ===================================================================== */
-    pthread_mutex_lock(&session->lock);
-    auto_gchar gchar* local_provider_name = g_strdup(session->provider_name);
-    AIProvider* local_provider = ai_provider_ref(session->provider);
-    auto_gchar gchar* local_model = g_strdup(session->model);
-    auto_gchar gchar* local_api_key = g_strdup(session->api_key ? session->api_key : "");
-    pthread_mutex_unlock(&session->lock);
-
-    log_debug("[AI-THREAD] Session: %s/%s", local_provider_name, local_model);
-    log_debug("[AI-THREAD] API key length: %zu", strlen(local_api_key));
+    log_debug("[AI-THREAD] Session: %s/%s", session->provider_name, session->model);
+    log_debug("[AI-THREAD] API key length: %zu", session->api_key ? strlen(session->api_key) : 0);
 
     /* Check for API key first */
-    if (!local_api_key || strlen(local_api_key) == 0) {
+    if (!session->api_key || strlen(session->api_key) == 0) {
         auto_gchar gchar* error_msg = g_strdup_printf("No API key set for provider '%s'. Use '/ai set token %s <key>' to configure.",
-                                                      local_provider_name, local_provider_name);
-        log_error("AI request failed for %s/%s: %s", local_provider_name, local_model, error_msg);
+                                                      session->provider_name, session->provider_name);
+        log_error("AI request failed for %s/%s: %s", session->provider_name, session->model, error_msg);
         _aiwin_display_error(user_data, error_msg);
-        ai_provider_unref(local_provider);
-        ai_session_unref(session);
         g_free(args);
         return NULL;
     }
@@ -1444,30 +1365,23 @@ _ai_request_thread(gpointer data)
     log_debug("[AI-THREAD] Curl initialized: %s", curl ? "OK" : "FAILED");
     if (!curl) {
         log_error("AI request failed for %s/%s: Failed to initialize curl",
-                  local_provider_name, local_model);
+                  session->provider_name, session->model);
         _aiwin_display_error(user_data, "Failed to initialize curl.");
-        ai_provider_unref(local_provider);
-        ai_session_unref(session);
         g_free(args);
         return NULL;
     }
 
-    /* Build JSON payload from history + prompt (under lock), then add user message to history */
-    log_debug("[AI-THREAD] Building JSON payload...");
-    pthread_mutex_lock(&session->lock);
-    auto_gchar gchar* json_payload = _build_json_payload_from_list(local_model, session->history, prompt);
-
-    /* Add user message to history now (it's in JSON but not yet in history) */
-    AIMessage* user_msg = g_new0(AIMessage, 1);
-    user_msg->role = g_strdup("user");
-    user_msg->content = g_strdup(prompt);
-    session->history = g_list_append(session->history, user_msg);
-    pthread_mutex_unlock(&session->lock);
+    /* Add user message to history FIRST */
+    ai_session_add_message(session, "user", prompt);
     log_debug("[AI-THREAD] Added user message to history");
+
+    /* Build JSON payload (includes the message we just added) */
+    log_debug("[AI-THREAD] Building JSON payload...");
+    auto_gchar gchar* json_payload = _build_json_payload(session, prompt);
     log_debug("[AI-THREAD] JSON payload: %s", json_payload);
 
     /* Build headers using shared helper */
-    struct curl_slist* headers = _build_curl_headers(local_provider, local_api_key);
+    struct curl_slist* headers = _build_curl_headers(session->provider, session->api_key);
 
     /* Response buffer */
     struct curl_response_t response;
@@ -1475,11 +1389,11 @@ _ai_request_thread(gpointer data)
     response.size = 0;
 
     /* Build request URL */
-    const gchar* api_url = local_provider->api_url;
+    const gchar* api_url = session->provider ? session->provider->api_url : DEFAULT_OPENAI_URL;
     auto_gchar gchar* request_url = g_strdup_printf("%s%sv1/responses", api_url, g_str_has_suffix(api_url, "/") ? "" : "/");
     log_debug("[AI-THREAD] API URL: %s", api_url);
     log_debug("[AI-THREAD] API Request URL: %s", request_url);
-    log_debug("[AI-THREAD] Model: %s", local_model);
+    log_debug("[AI-THREAD] Model: %s", session->model);
 
     /* Set URL and execute request */
     curl_easy_setopt(curl, CURLOPT_URL, request_url);
@@ -1496,36 +1410,33 @@ _ai_request_thread(gpointer data)
     long http_code = 0;
     curl_easy_getinfo(curl, CURLINFO_RESPONSE_CODE, &http_code);
     log_debug("[AI-THREAD] HTTP response code: %ld", http_code);
-    auto_gchar gchar* response_data = g_steal_pointer(&response.data);
 
     if (res != CURLE_OK) {
         auto_gchar gchar* error_msg = g_strdup(curl_easy_strerror(res));
-        log_error("AI request failed for %s/%s: %s", local_provider_name, local_model, error_msg);
+        log_error("AI request failed for %s/%s: %s", session->provider_name, session->model, error_msg);
         _aiwin_display_error(user_data, error_msg);
     } else if (http_code >= 400) {
         /* Handle HTTP errors */
         log_debug("[AI-THREAD] HTTP error response body (%zu bytes): %s",
-                  response.size, response_data);
+                  response.size, response.data ? response.data : "NULL");
         /* Try to extract the actual error message from the JSON response */
-        auto_gchar gchar* parsed_error = ai_parse_error_message(response_data);
-        auto_gchar gchar* error_msg = parsed_error ? g_strdup_printf("HTTP %ld: %s", http_code, parsed_error) : g_strdup_printf("HTTP %ld: %s", http_code, response_data && strlen(response_data) > 0 ? response_data : "Unknown error");
-        log_error("AI request failed for %s/%s: %s", local_provider_name, local_model, error_msg);
+        auto_gchar gchar* parsed_error = ai_parse_error_message(response.data);
+        auto_gchar gchar* error_msg = parsed_error ? g_strdup_printf("HTTP %ld: %s", http_code, parsed_error) : g_strdup_printf("HTTP %ld: %s", http_code, response.data && strlen(response.data) > 0 ? response.data : "Unknown error");
+        log_error("AI request failed for %s/%s: %s", session->provider_name, session->model, error_msg);
         _aiwin_display_error(user_data, error_msg);
     } else {
-        log_debug("[AI-THREAD] Raw API response (%zu bytes): %s", response.size, response_data);
+        /* Parse response - transfer ownership to auto_gchar for cleanup */
+        log_debug("[AI-THREAD] Raw API response (%zu bytes): %s", response.size, response.data ? response.data : "NULL");
+        auto_gchar gchar* response_data = response.data;
+        response.data = NULL;
         auto_gchar gchar* content = ai_parse_response(response_data);
         if (content) {
-            /* Add assistant response to history (under lock) */
-            pthread_mutex_lock(&session->lock);
-            AIMessage* assistant_msg = g_new0(AIMessage, 1);
-            assistant_msg->role = g_strdup("assistant");
-            assistant_msg->content = g_strdup(content);
-            session->history = g_list_append(session->history, assistant_msg);
-            pthread_mutex_unlock(&session->lock);
+            /* Add assistant response to history */
+            ai_session_add_message(session, "assistant", content);
             _aiwin_display_response(user_data, content);
         } else {
             log_error("AI response parse failed for %s/%s: %.200s...",
-                      local_provider_name, local_model, response_data);
+                      session->provider_name, session->model, response_data);
             _aiwin_display_error(user_data, "Failed to parse AI response.");
         }
     }
@@ -1533,9 +1444,6 @@ _ai_request_thread(gpointer data)
     curl_slist_free_all(headers);
     curl_easy_cleanup(curl);
 
-    ai_provider_unref(local_provider);
-
-    ai_session_unref(session);
     g_free(args);
 
     return NULL;

src/ai/ai_client.h

@@ -19,6 +19,7 @@ typedef struct ai_provider_t
 {
     gchar* name;           /* Provider name (e.g., "openai", "perplexity") */
     gchar* api_url;        /* API endpoint URL */
+    gchar* org_id;         /* Optional organization ID */
     gchar* project_id;     /* Optional project ID (for some providers) */
     gchar* default_model;  /* Default model for this provider */
     GHashTable* settings;  /* Extensible per-provider settings (e.g., tools=enabled, search=disabled) */
@@ -32,7 +33,6 @@ typedef struct ai_provider_t
  */
 typedef struct ai_session_t
 {
-    pthread_mutex_t lock; /* Protects all session fields below */
     gchar* provider_name; /* Provider name */
     AIProvider* provider; /* Provider configuration */
     gchar* model;         /* Model identifier (e.g., "gpt-4", "sonar") */
@@ -66,9 +66,10 @@ AIProvider* ai_get_provider(const gchar* name);
  * Add or update a provider configuration.
  * @param name The provider name
  * @param api_url The API endpoint URL
+ * @param org_id Optional organization ID (can be NULL)
  * @return New AIProvider* (caller must unref when done)
  */
-AIProvider* ai_add_provider(const gchar* name, const gchar* api_url);
+AIProvider* ai_add_provider(const gchar* name, const gchar* api_url, const gchar* org_id);
 
 /**
  * Remove a provider by name.
@@ -77,13 +78,6 @@ AIProvider* ai_add_provider(const gchar* name, const gchar* api_url);
  */
 gboolean ai_remove_provider(const gchar* name);
 
-/**
- * Increment the reference count of a provider.
- * @param provider The provider to reference
- * @return The same provider pointer
- */
-AIProvider* ai_provider_ref(AIProvider* provider);
-
 /**
  * Decrement the reference count of a provider.
  * @param provider The provider to unreference
@@ -107,10 +101,13 @@ GList* ai_list_providers(void);
 gchar* ai_providers_find(const char* const search_str, gboolean previous, void* context);
 
 /**
- * Reset the provider autocomplete state.
- * Called from cmd_ac_reset() to clear autocomplete state.
+ * Find a model name for autocomplete.
+ * @param search_str The search string
+ * @param previous Whether to go to previous match
+ * @param context ProfAiWin* for the current session
+ * @return Model name, or NULL if not found
  */
-void ai_providers_reset_ac(void);
+gchar* ai_models_find(const char* const search_str, gboolean previous, void* context);
 
 /**
  * Get the API key for a provider.
@@ -254,19 +251,6 @@ const gchar* ai_session_get_model(AISession* session);
  */
 void ai_session_set_model(AISession* session, const gchar* model);
 
-/**
- * Atomically switch session provider, model, and API key.
- * All mutations happen under the session lock to prevent races with
- * _ai_request_thread() which snapshots session state before making requests.
- *
- * @param session The session
- * @param provider_name New provider name
- * @param model New model identifier
- * @param api_key New API key (caller must free after calling this)
- */
-void ai_session_switch(AISession* session, const gchar* provider_name,
-                       const gchar* model, gchar* api_key);
-
 /* ========================================================================
  * Request Handling
  * ======================================================================== */

src/command/cmd_ac.c

@@ -70,6 +70,7 @@
 
 static char* _sub_autocomplete(ProfWin* window, const char* const input, gboolean previous);
 static char* _notify_autocomplete(ProfWin* window, const char* const input, gboolean previous);
+static char* _ai_model_autocomplete(ProfWin* window, const char* const input, gboolean previous, const char* prefix);
 static char* _theme_autocomplete(ProfWin* window, const char* const input, gboolean previous);
 static char* _autoaway_autocomplete(ProfWin* window, const char* const input, gboolean previous);
 static char* _autoconnect_autocomplete(ProfWin* window, const char* const input, gboolean previous);
@@ -468,8 +469,7 @@ static Autocomplete* all_acs[] = {
     &ai_subcommands_ac,
     &ai_set_subcommands_ac,
     &ai_set_custom_subcommands_ac,
-    &ai_remove_subcommands_ac,
-    &ai_models_ac
+    &ai_remove_subcommands_ac
 };
 
 static GHashTable* ac_funcs = NULL;
@@ -1192,6 +1192,7 @@ cmd_ac_init(void)
 
     autocomplete_add_unsorted(ai_set_subcommands_ac, "provider", FALSE);
     autocomplete_add_unsorted(ai_set_subcommands_ac, "token", FALSE);
+    autocomplete_add_unsorted(ai_set_subcommands_ac, "default-provider", FALSE);
     autocomplete_add_unsorted(ai_set_subcommands_ac, "default-model", FALSE);
     autocomplete_add_unsorted(ai_set_subcommands_ac, "custom", FALSE);
 
@@ -1696,7 +1697,6 @@ cmd_ac_reset(ProfWin* window)
     win_reset_search_attempts();
     win_close_reset_search_attempts();
     plugins_reset_autocomplete();
-    ai_providers_reset_ac();
 }
 
 void
@@ -4487,10 +4487,6 @@ _force_encryption_autocomplete(ProfWin* window, const char* const input, gboolea
     return result;
 }
 
-/* Forward declaration */
-static char* _ai_provider_and_model_autocomplete(ProfWin* window, const char* const input,
-                                                 gboolean previous, const char* cmd);
-
 static char*
 _ai_autocomplete(ProfWin* window, const char* const input, gboolean previous)
 {
@@ -4499,6 +4495,7 @@ _ai_autocomplete(ProfWin* window, const char* const input, gboolean previous)
     /* Parse once for reuse - /ai <subcommand> [<arg1>] [<arg2>] */
     gboolean parse_result = FALSE;
     auto_gcharv gchar** args = parse_args(input, 1, 4, &parse_result);
+    gboolean space_at_end = g_str_has_suffix(input, " ");
     int num_args = g_strv_length(args);
 
     /* Top-level /ai <subcommand> autocomplete (e.g., /ai s<tab> -> /ai set) */
@@ -4513,6 +4510,12 @@ _ai_autocomplete(ProfWin* window, const char* const input, gboolean previous)
         return result;
     }
 
+    // /ai set default-provider <provider> - autocomplete provider names
+    result = autocomplete_param_with_func(input, "/ai set default-provider", ai_providers_find, previous, NULL);
+    if (result) {
+        return result;
+    }
+
     // /ai set default-model <provider> <model> - autocomplete provider names
     result = autocomplete_param_with_func(input, "/ai set default-model", ai_providers_find, previous, NULL);
     if (result) {
@@ -4554,20 +4557,34 @@ _ai_autocomplete(ProfWin* window, const char* const input, gboolean previous)
         return result;
     }
 
-    // /ai start <provider> <model> - autocomplete provider names and model names
-    result = _ai_provider_and_model_autocomplete(window, input, previous, "/ai start");
+    // /ai start [<provider>] [<model>] - use shared parse_args
+    if (parse_result && args && args[0] != NULL && g_strcmp0(args[0], "start") == 0) {
+        /* args[0]="start", args[1]=provider (if typed), args[2]=model (if typed) */
+        if (num_args == 1 || (num_args == 2 && !space_at_end)) {
+            result = autocomplete_param_with_func(input, "/ai start", ai_providers_find, previous, NULL);
+        } else {
+            /* /ai start <provider> <model> - model autocomplete */
+            result = _ai_model_autocomplete(window, input, previous, "/ai start ");
+        }
+        if (result) {
+            return result;
+        }
+    }
+
+    // /ai switch <provider> <model> - autocomplete model names for specified provider
+    result = _ai_model_autocomplete(window, input, previous, "/ai switch");
     if (result) {
         return result;
     }
 
-    // /ai switch <provider> <model> - autocomplete provider names and model names
-    result = _ai_provider_and_model_autocomplete(window, input, previous, "/ai switch");
+    result = autocomplete_param_with_func(input, "/ai switch", ai_providers_find, previous, NULL);
     if (result) {
         return result;
     }
 
-    // /ai set default-model <provider> <model> - autocomplete provider names and model names
-    result = _ai_provider_and_model_autocomplete(window, input, previous, "/ai set default-model");
+    // /ai switch <model> - autocomplete model names from current session's provider
+    ProfAiWin* aiwin = (window && window->type == WIN_AI) ? (ProfAiWin*)window : wins_get_ai();
+    result = autocomplete_param_with_func(input, "/ai switch", ai_models_find, previous, aiwin);
     if (result) {
         return result;
     }
@@ -4587,26 +4604,13 @@ _ai_autocomplete(ProfWin* window, const char* const input, gboolean previous)
 }
 
 /**
- * Autocomplete provider names and model names for /ai <cmd> <provider> <model> patterns.
- * First tries to autocomplete provider names, then model names if provider is valid.
+ * Autocomplete model names for /ai <cmd> <provider> <model> patterns.
+ * Extracts provider from input and provides model completions from that provider's cached models.
  * Uses static ai_models_ac to preserve cycling state (last_found) across calls.
- * The cmd_prefix should NOT include trailing space (e.g., "/ai start" not "/ai start ").
  */
 static char*
-_ai_provider_and_model_autocomplete(ProfWin* window, const char* const input, gboolean previous, const char* cmd)
+_ai_model_autocomplete(ProfWin* window, const char* const input, gboolean previous, const char* cmd_prefix)
 {
-    char* result;
-
-    /* First, try provider name autocomplete */
-    result = autocomplete_param_with_func(input, cmd, ai_providers_find, previous, NULL);
-    if (result) {
-        return result;
-    }
-
-    /* Provider was specified, try model name autocomplete */
-    /* Build the full command prefix with space */
-    auto_gchar gchar* cmd_prefix = g_strdup_printf("%s ", cmd);
-
     if (!g_str_has_prefix(input, cmd_prefix)) {
         return NULL;
     }
@@ -4642,6 +4646,6 @@ _ai_provider_and_model_autocomplete(ProfWin* window, const char* const input, gb
 
     auto_gchar gchar* full_prefix = g_strdup_printf("%s%s", cmd_prefix, rest);
 
-    result = autocomplete_param_with_ac(input, full_prefix, ai_models_ac, TRUE, previous);
+    char* result = autocomplete_param_with_ac(input, full_prefix, ai_models_ac, TRUE, previous);
     return result;
 }

src/command/cmd_defs.c

@@ -2804,6 +2804,7 @@ static const struct cmd_t command_defs[] = {
               "/ai",
               "/ai set provider <name> <url>",
               "/ai set token <provider> <token>",
+              "/ai set default-provider <provider>",
               "/ai set default-model <provider> <model>",
               "/ai set custom <provider> <setting> <value>",
               "/ai remove provider <name>",
@@ -2822,12 +2823,14 @@ static const struct cmd_t command_defs[] = {
               { "", "Display current AI settings and configured providers" },
               { "set provider <name> <url>", "Add or update a provider with custom API endpoint" },
               { "set token <provider> <token>", "Set API token for a provider (e.g., openai, perplexity)" },
+              { "set default-provider <provider>", "Set global default provider for /ai start" },
               { "set default-model <provider> <model>", "Set default model for a provider" },
               { "set custom <provider> <setting> <value>", "Set provider-level setting (e.g., tools, search)" },
               { "remove provider <name>", "Remove a custom provider" },
               { "providers", "List configured providers with full details" },
-              { "start <provider> [<model>]", "Start new AI chat (space-separated, uses defaults if omitted)" },
+              { "start [<provider>] [<model>]", "Start new AI chat (space-separated, uses defaults if omitted)" },
               { "switch <provider> [<model>]", "Switch to different provider (and optionally model)" },
+              { "switch <model>", "Change model in current session (keeps provider)" },
               { "models <provider>", "Fetch and display available models for provider" },
               { "clear", "Clear current chat history" })
       CMD_EXAMPLES(
@@ -2835,6 +2838,7 @@ static const struct cmd_t command_defs[] = {
               "/ai set token openai sk-xxx",
               "/ai set token perplexity pplx-xxx",
               "/ai set provider custom https://my-api.com/v1/chat/completions",
+              "/ai set default-provider perplexity",
               "/ai set default-model perplexity sonar",
               "/ai set custom perplexity tools enabled",
               "/ai remove provider custom",

src/command/cmd_funcs.c

@@ -8516,8 +8516,7 @@ _cmd_execute_default(ProfWin* window, const char* inp)
     case WIN_AI:
     {
         ProfAiWin* aiwin = (ProfAiWin*)window;
-        auto_gchar gchar* stanza_id = connection_create_stanza_id();
-        cl_ev_send_ai_msg(aiwin, inp, stanza_id);
+        cl_ev_send_ai_msg(aiwin, inp, NULL);
         break;
     }
     default:
@@ -10818,6 +10817,7 @@ cmd_ai(ProfWin* window, const char* const command, gchar** args)
 
         cons_show("Use '/ai start' to begin a chat (uses default provider/model).");
         cons_show("Use '/ai models <provider>' to fetch available models.");
+        cons_show("Available models: https://models.litellm.ai/");
         return TRUE;
     }
 
@@ -10839,7 +10839,7 @@ cmd_ai_set(ProfWin* window, const char* const command, gchar** args)
             cons_bad_cmd_usage(command);
             return TRUE;
         }
-        if (ai_add_provider(args[2], args[3])) {
+        if (ai_add_provider(args[2], args[3], NULL)) {
             cons_show("Provider '%s' configured with URL: %s", args[2], args[3]);
         } else {
             cons_show_error("Failed to configure provider '%s'.", args[2]);
@@ -10876,6 +10876,23 @@ cmd_ai_set(ProfWin* window, const char* const command, gchar** args)
         cons_show("Setting '%s' for provider '%s' set to: %s", args[3], args[2], args[4]);
         cons_show("");
         return TRUE;
+    } else if (g_strcmp0(args[1], "default-provider") == 0) {
+        // /ai set default-provider <provider>
+        if (g_strv_length(args) < 3) {
+            cons_bad_cmd_usage(command);
+            return TRUE;
+        }
+        const gchar* provider_name = args[2];
+        AIProvider* provider = ai_get_provider(provider_name);
+        if (!provider) {
+            cons_show_error("Provider '%s' not found. Use '/ai set provider %s <url>' to add it.",
+                            provider_name, provider_name);
+            return TRUE;
+        }
+        prefs_set_string(PREF_AI_PROVIDER, provider_name);
+        cons_show("Default provider set to: %s", provider_name);
+        cons_show("");
+        return TRUE;
     }
 
     cons_bad_cmd_usage(command);
@@ -10944,11 +10961,8 @@ cmd_ai_start(ProfWin* window, const char* const command, gchar** args)
     if (!model) {
         model = ai_get_provider_default_model(provider_name);
     }
-
     if (!model) {
-        cons_show_error("No model specified and no default model set for provider '%s'.", provider_name);
-        cons_show("Use '/ai set default-model %s <model>'.", provider_name);
-        return TRUE;
+        model = "gpt-4o"; // Fallback
     }
 
     // Check for API key
@@ -10981,9 +10995,6 @@ cmd_ai_start(ProfWin* window, const char* const command, gchar** args)
     }
     log_debug("[AI-CMD] wins_new_ai() returned successfully, window type: %d", ai_win->type);
 
-    // Release the reference held by cmd_ai_start, since the window now holds one
-    ai_session_unref(session);
-
     // Add welcome message to the AI window
     log_debug("[AI-CMD] Adding welcome messages...");
     win_println(ai_win, THEME_DEFAULT, "-", "AI Chat: %s/%s", provider_name, model);
@@ -11013,12 +11024,12 @@ cmd_ai_model(ProfWin* window, const char* const command, gchar** args)
 
     const gchar* model = args[1];
 
-    // Must be in an AI window to use this command
-    if (!window || window->type != WIN_AI) {
-        cons_show_error("Must be in an AI chat window to use this command.");
+    // Get current AI window
+    ProfAiWin* aiwin = (window && window->type == WIN_AI) ? (ProfAiWin*)window : wins_get_ai();
+    if (!aiwin) {
+        cons_show("No active AI chat window. Use '/ai start' first.");
         return TRUE;
     }
-    ProfAiWin* aiwin = (ProfAiWin*)window;
 
     assert(aiwin->memcheck == PROFAIWIN_MEMCHECK);
 
@@ -11044,12 +11055,12 @@ cmd_ai_switch(ProfWin* window, const char* const command, gchar** args)
         return TRUE;
     }
 
-    // Must be in an AI window to use this command
-    if (!window || window->type != WIN_AI) {
-        cons_show_error("Must be in an AI chat window to use this command.");
+    // Get current AI window
+    ProfAiWin* aiwin = (window && window->type == WIN_AI) ? (ProfAiWin*)window : wins_get_ai();
+    if (!aiwin) {
+        cons_show("No active AI chat window. Use '/ai start' first.");
         return TRUE;
     }
-    ProfAiWin* aiwin = (ProfAiWin*)window;
 
     assert(aiwin->memcheck == PROFAIWIN_MEMCHECK);
 
@@ -11063,12 +11074,14 @@ cmd_ai_switch(ProfWin* window, const char* const command, gchar** args)
 
     const gchar* provider_name;
     const gchar* model;
+    gboolean changed_provider = FALSE;
 
     // Check if arg1 is a known provider
     AIProvider* provider = ai_get_provider(arg1);
     if (provider) {
         // arg1 is a provider name
         provider_name = arg1;
+        changed_provider = TRUE;
 
         // Get model: arg2 > provider default > error
         if (arg2) {
@@ -11084,10 +11097,6 @@ cmd_ai_switch(ProfWin* window, const char* const command, gchar** args)
     } else {
         // arg1 is a model name, keep current provider
         provider_name = aiwin->session->provider_name;
-        if (!provider_name) {
-            cons_show_error("Session has no provider name.");
-            return TRUE;
-        }
         model = arg1;
     }
 
@@ -11099,8 +11108,19 @@ cmd_ai_switch(ProfWin* window, const char* const command, gchar** args)
         return TRUE;
     }
 
-    // Atomically switch session provider, model, and API key (thread-safe)
-    ai_session_switch(aiwin->session, provider_name, model, g_steal_pointer(&api_key));
+    // Update the existing session's provider and model
+    if (changed_provider) {
+        AIProvider* new_provider = ai_get_provider(provider_name);
+        g_free(aiwin->session->provider_name);
+        aiwin->session->provider_name = g_strdup(provider_name);
+        ai_provider_unref(aiwin->session->provider);
+        aiwin->session->provider = new_provider;
+        aiwin->session->provider->ref_count++;
+    }
+    g_free(aiwin->session->model);
+    aiwin->session->model = g_strdup(model);
+    g_free(aiwin->session->api_key);
+    aiwin->session->api_key = g_strdup(api_key);
 
     // Update window title
     win_println((ProfWin*)aiwin, THEME_DEFAULT, "-", "AI Chat: %s/%s", provider_name, model);
@@ -11147,7 +11167,8 @@ cmd_ai_models(ProfWin* window, const char* const command, gchar** args)
         cons_show("Use '/ai models %s' to fetch fresh models from the API.", provider_name);
     } else {
         // Default: fetch fresh models from API
-        ai_fetch_models(provider_name, window);
+        ProfAiWin* aiwin = (window && window->type == WIN_AI) ? (ProfAiWin*)window : wins_get_ai();
+        ai_fetch_models(provider_name, aiwin);
     }
 
     return TRUE;
@@ -11157,44 +11178,103 @@ gboolean
 cmd_ai_clear(ProfWin* window, const char* const command, gchar** args)
 {
     // /ai clear
-    // Must be in an AI window to use this command
-    if (!window || window->type != WIN_AI) {
-        cons_show_error("Must be in an AI chat window to use this command.");
+    ProfAiWin* aiwin = (window && window->type == WIN_AI) ? (ProfAiWin*)window : wins_get_ai();
+
+    if (aiwin) {
+        assert(aiwin->memcheck == PROFAIWIN_MEMCHECK);
+        if (aiwin->session) {
+            ai_session_clear_history(aiwin->session);
+        }
+        cons_show("Chat history cleared.");
+    } else {
+        cons_show("No active AI chat window to clear.");
+    }
+    cons_show("");
+    return TRUE;
+}
+
+gboolean
+cmd_ai_correct(ProfWin* window, const char* const command, gchar** args)
+{
+    // /ai correct <message>
+    // Join all arguments from args[1] onwards to support multi-word prompts
+    auto_gchar gchar* prompt = g_strjoinv(" ", &args[1]);
+    if (prompt == NULL || strlen(prompt) == 0) {
+        cons_bad_cmd_usage(command);
         return TRUE;
     }
-    ProfAiWin* aiwin = (ProfAiWin*)window;
 
-    assert(aiwin->memcheck == PROFAIWIN_MEMCHECK);
-    if (aiwin->session) {
-        ai_session_clear_history(aiwin->session);
+    // Get current AI window
+    ProfAiWin* aiwin = wins_get_ai();
+    if (!aiwin) {
+        cons_show("No active AI chat window. Use '/ai start <provider>/<model>' first.");
+        return TRUE;
     }
 
-    win_clear(window);
-    cons_show("AI Chat history cleared.");
+    assert(aiwin->memcheck == PROFAIWIN_MEMCHECK);
+
+    if (!aiwin->session) {
+        cons_show("No active session in this chat window.");
+        return TRUE;
+    }
+
+    // Get the last user message and replace it
+    GList* history = aiwin->session->history;
+    GList* last_user_msg = NULL;
+    for (GList* curr = history; curr; curr = g_list_next(curr)) {
+        AIMessage* msg = curr->data;
+        if (g_strcmp0(msg->role, "user") == 0) {
+            last_user_msg = curr;
+        }
+    }
+
+    if (!last_user_msg) {
+        cons_show("No user messages in this chat to correct.");
+        return TRUE;
+    }
+
+    // Replace the last user message
+    AIMessage* msg = last_user_msg->data;
+    g_free(msg->content);
+    msg->content = g_strdup(prompt);
+
+    // Resend the prompt
+    cons_show("Correcting message...");
+    ai_send_prompt(aiwin->session, prompt, aiwin);
+
     return TRUE;
 }
 
 gboolean
 cmd_ai_providers(ProfWin* window, const char* const command, gchar** args)
 {
+    if (args[1] == NULL || g_strcmp0(args[1], "list") != 0) {
+        // List all available providers
+        cons_show("Available AI providers:");
+        cons_show("");
+        cons_show("  openai      - OpenAI API (https://api.openai.com)");
+        cons_show("  perplexity  - Perplexity API (https://api.perplexity.ai)");
+        cons_show("");
+        cons_show("Add custom providers with: /ai set provider <name> <url>");
+        return TRUE;
+    }
+
+    // List configured providers with key status
     cons_show("Configured providers:");
     cons_show("");
 
     GList* providers = ai_list_providers();
-    if (!providers) {
-        cons_show("  (none configured)");
-        cons_show("");
-        cons_show("Add a provider with: /ai set provider <name> <url>");
-        return TRUE;
-    }
-
     for (GList* curr = providers; curr; curr = g_list_next(curr)) {
         AIProvider* provider = curr->data;
-        auto_gchar gchar* key = ai_get_provider_key(provider->name);
+        gchar* key = ai_get_provider_key(provider->name);
         cons_show("  %s", provider->name);
         cons_show("    URL: %s", provider->api_url);
         cons_show("    Key: %s", key ? "configured" : "NOT configured");
+        if (provider->org_id && strlen(provider->org_id) > 0) {
+            cons_show("    Org: %s", provider->org_id);
+        }
         cons_show("");
+        g_free(key);
     }
     g_list_free(providers);
 

src/config/preferences.c

@@ -67,8 +67,6 @@
 #define PREF_GROUP_PLUGINS       "plugins"
 #define PREF_GROUP_EXECUTABLES   "executables"
 #define PREF_GROUP_AI            "ai"
-#define PREF_GROUP_AI_PREFIX     "ai/"      /* per-provider subsection prefix: [ai/<provider>] */
-#define PREF_AI_SETTING_PREFIX   "setting." /* per-provider custom setting key prefix */
 
 #define INPBLOCK_DEFAULT 1000
 
@@ -245,69 +243,6 @@ _prefs_load(void)
         g_key_file_remove_key(prefs, PREF_GROUP_UI, "titlebar.muc.title.jid", NULL);
         g_key_file_remove_key(prefs, PREF_GROUP_UI, "titlebar.muc.title.name", NULL);
     }
-
-    /* Migrate legacy flat [ai] layout
-     *   openai_url=..., openai=<token>, openai_models=..., openai_default_model=...
-     * into per-provider subsections
-     *   [ai/openai] url=..., key=..., models=..., default_model=...
-     * Idempotent: once the flat keys are gone, this is a no-op. */
-    if (g_key_file_has_group(prefs, PREF_GROUP_AI)) {
-        gsize key_count = 0;
-        auto_gcharv gchar** all_keys = g_key_file_get_keys(prefs, PREF_GROUP_AI, &key_count, NULL);
-
-        /* Collect provider names from <name>_url keys first so we can migrate
-         * the whole bundle (url + token + models + default_model) atomically
-         * per provider, without misclassifying unrelated flat keys. */
-        GHashTable* to_migrate = g_hash_table_new_full(g_str_hash, g_str_equal, g_free, NULL);
-        for (gsize i = 0; i < key_count; i++) {
-            const gchar* k = all_keys[i];
-            if (g_str_has_suffix(k, "_url") && !g_str_has_suffix(k, "_models_url")) {
-                gsize klen = strlen(k);
-                if (klen > 4) {
-                    g_hash_table_add(to_migrate, g_strndup(k, klen - 4));
-                }
-            }
-        }
-
-        GList* provider_names = g_hash_table_get_keys(to_migrate);
-        for (GList* curr = provider_names; curr; curr = g_list_next(curr)) {
-            const gchar* name = (const gchar*)curr->data;
-            auto_gchar gchar* group = g_strconcat(PREF_GROUP_AI_PREFIX, name, NULL);
-
-            const struct
-            {
-                const gchar* flat_suffix;
-                const gchar* new_key;
-            } map[] = {
-                { "_url", "url" },
-                { "_models", "models" },
-                { "_default_model", "default_model" },
-                { NULL, NULL },
-            };
-            for (int j = 0; map[j].flat_suffix; j++) {
-                auto_gchar gchar* flat_key = g_strconcat(name, map[j].flat_suffix, NULL);
-                if (g_key_file_has_key(prefs, PREF_GROUP_AI, flat_key, NULL)) {
-                    auto_gchar gchar* val = g_key_file_get_string(prefs, PREF_GROUP_AI, flat_key, NULL);
-                    if (val) {
-                        g_key_file_set_string(prefs, group, map[j].new_key, val);
-                    }
-                    g_key_file_remove_key(prefs, PREF_GROUP_AI, flat_key, NULL);
-                }
-            }
-
-            /* Token was stored as the bare provider name in [ai]. */
-            if (g_key_file_has_key(prefs, PREF_GROUP_AI, name, NULL)) {
-                auto_gchar gchar* val = g_key_file_get_string(prefs, PREF_GROUP_AI, name, NULL);
-                if (val) {
-                    g_key_file_set_string(prefs, group, "key", val);
-                }
-                g_key_file_remove_key(prefs, PREF_GROUP_AI, name, NULL);
-            }
-        }
-        g_list_free(provider_names);
-        g_hash_table_destroy(to_migrate);
-    }
-
     _save_prefs();
 
     boolean_choice_ac = autocomplete_new();
@@ -1773,103 +1708,73 @@ _save_prefs(void)
 }
 
 /* ========================================================================
- * AI provider preferences
- *
- * Each provider lives in its own [ai/<name>] subsection of the keyfile with:
- *   url=...
- *   key=<api token>
- *   default_model=...
- *   models=model1;model2;...
- *   setting.<custom>=value     (e.g. setting.tools=enabled)
- * The bare [ai] section keeps only the global "defaults_initialized" sentinel.
- * Legacy flat-key layouts are migrated on first load in _prefs_load().
+ * AI Token Management
  * ======================================================================== */
 
-static gchar*
-_ai_section(const char* const provider)
-{
-    return g_strconcat(PREF_GROUP_AI_PREFIX, provider, NULL);
-}
-
-static gboolean
-_ai_set_string(const char* const provider, const char* const key, const char* const value)
-{
-    if (!provider || !key || !value || !prefs)
-        return FALSE;
-
-    auto_gchar gchar* group = _ai_section(provider);
-    g_key_file_set_string(prefs, group, key, value);
-    _save_prefs();
-    return TRUE;
-}
-
-static char*
-_ai_get_string(const char* const provider, const char* const key)
-{
-    if (!provider || !key || !prefs)
-        return NULL;
-
-    auto_gchar gchar* group = _ai_section(provider);
-    if (!g_key_file_has_key(prefs, group, key, NULL))
-        return NULL;
-    return g_key_file_get_string(prefs, group, key, NULL);
-}
-
-static gboolean
-_ai_remove_string(const char* const provider, const char* const key)
-{
-    if (!provider || !key || !prefs)
-        return FALSE;
-
-    auto_gchar gchar* group = _ai_section(provider);
-    if (!g_key_file_has_key(prefs, group, key, NULL))
-        return FALSE;
-
-    g_key_file_remove_key(prefs, group, key, NULL);
-    _save_prefs();
-    return TRUE;
-}
-
-/* --- Token --- */
-
 gboolean
 prefs_ai_set_token(const char* const provider, const char* const token)
 {
-    if (!provider || !prefs)
+    if (!provider)
         return FALSE;
-    if (!token)
+
+    if (!prefs)
+        return FALSE;
+
+    if (token) {
+        g_key_file_set_string(prefs, PREF_GROUP_AI, provider, token);
+        _save_prefs();
+        return TRUE;
+    } else {
         return prefs_ai_remove_token(provider);
-    return _ai_set_string(provider, "key", token);
+    }
 }
 
 gboolean
 prefs_ai_remove_token(const char* const provider)
 {
-    return _ai_remove_string(provider, "key");
+    if (!provider)
+        return FALSE;
+
+    if (!prefs)
+        return FALSE;
+
+    if (!g_key_file_has_key(prefs, PREF_GROUP_AI, provider, NULL)) {
+        return FALSE;
+    }
+
+    g_key_file_remove_key(prefs, PREF_GROUP_AI, provider, NULL);
+    _save_prefs();
+    return TRUE;
 }
 
 char*
 prefs_ai_get_token(const char* const provider)
 {
-    return _ai_get_string(provider, "key");
+    if (!provider || !prefs)
+        return NULL;
+
+    return g_key_file_get_string(prefs, PREF_GROUP_AI, provider, NULL);
 }
 
 GList*
 prefs_ai_list_tokens(void)
 {
-    if (!prefs)
+    if (!prefs || !g_key_file_has_group(prefs, PREF_GROUP_AI)) {
         return NULL;
+    }
 
     GList* result = NULL;
-    GList* providers = prefs_ai_list_providers();
-    for (GList* curr = providers; curr; curr = g_list_next(curr)) {
-        const gchar* name = (const gchar*)curr->data;
-        auto_gchar gchar* tok = prefs_ai_get_token(name);
-        if (tok && tok[0] != '\0') {
+    gsize len;
+    auto_gcharv gchar** keys = g_key_file_get_keys(prefs, PREF_GROUP_AI, &len, NULL);
+
+    for (gsize i = 0; i < len; i++) {
+        char* name = keys[i];
+        auto_gchar gchar* value = g_key_file_get_string(prefs, PREF_GROUP_AI, name, NULL);
+        if (value) {
             result = g_list_append(result, g_strdup(name));
         }
     }
-    prefs_free_ai_providers(providers);
+
     return result;
 }
 
@@ -1881,45 +1786,72 @@ prefs_free_ai_tokens(GList* tokens)
     }
 }
 
-/* --- Models cache --- */
-
 gboolean
 prefs_ai_set_models(const char* const provider, const gchar* const* models, gint count)
 {
-    if (!provider || count <= 0 || !prefs)
+    if (!provider || count <= 0)
         return FALSE;
 
+    if (!prefs)
+        return FALSE;
+
+    /* Build semicolon-separated model list */
     GString* model_str = g_string_new("");
     for (int i = 0; i < count; i++) {
-        if (i > 0)
+        if (i > 0) {
             g_string_append_c(model_str, ';');
+        }
         g_string_append(model_str, models[i]);
     }
 
-    gboolean ok = _ai_set_string(provider, "models", model_str->str);
+    g_key_file_set_string(prefs, PREF_GROUP_AI, g_strconcat(provider, "_models", NULL), model_str->str);
     g_string_free(model_str, TRUE);
-    return ok;
+    _save_prefs();
+    return TRUE;
 }
 
 gboolean
 prefs_ai_remove_models(const char* const provider)
 {
-    return _ai_remove_string(provider, "models");
+    if (!provider)
+        return FALSE;
+
+    if (!prefs)
+        return FALSE;
+
+    auto_gchar gchar* key = g_strconcat(provider, "_models", NULL);
+    if (!g_key_file_has_key(prefs, PREF_GROUP_AI, key, NULL)) {
+        return FALSE;
+    }
+
+    g_key_file_remove_key(prefs, PREF_GROUP_AI, key, NULL);
+    _save_prefs();
+    return TRUE;
 }
 
 GList*
 prefs_ai_get_models(const char* const provider)
 {
-    auto_gchar gchar* model_str = _ai_get_string(provider, "models");
-    if (!model_str || model_str[0] == '\0')
+    if (!provider || !prefs)
         return NULL;
 
+    auto_gchar gchar* key = g_strconcat(provider, "_models", NULL);
+    if (!g_key_file_has_key(prefs, PREF_GROUP_AI, key, NULL)) {
+        return NULL;
+    }
+
+    auto_gchar gchar* model_str = g_key_file_get_string(prefs, PREF_GROUP_AI, key, NULL);
+    if (!model_str || strlen(model_str) == 0) {
+        return NULL;
+    }
+
     GList* result = NULL;
     gchar** models = g_strsplit(model_str, ";", -1);
     for (int i = 0; models[i] != NULL; i++) {
         result = g_list_append(result, g_strdup(models[i]));
     }
     g_strfreev(models);
+
     return result;
 }
 
@@ -1931,207 +1863,6 @@ prefs_free_ai_models(GList* models)
     }
 }
 
-/* --- Default model --- */
-
-gboolean
-prefs_ai_set_default_model(const char* const provider, const char* const model)
-{
-    if (!provider || !model || !prefs)
-        return FALSE;
-    if (model[0] == '\0')
-        return prefs_ai_remove_default_model(provider);
-    return _ai_set_string(provider, "default_model", model);
-}
-
-gboolean
-prefs_ai_remove_default_model(const char* const provider)
-{
-    return _ai_remove_string(provider, "default_model");
-}
-
-char*
-prefs_ai_get_default_model(const char* const provider)
-{
-    return _ai_get_string(provider, "default_model");
-}
-
-/* --- Provider URL --- */
-
-gboolean
-prefs_ai_set_provider(const char* const provider, const char* const url)
-{
-    if (!provider || !url)
-        return FALSE;
-    return _ai_set_string(provider, "url", url);
-}
-
-gboolean
-prefs_ai_remove_provider(const char* const provider)
-{
-    /* Provider presence is identified by the url key; removing it is what
-     * makes prefs_ai_list_providers stop returning this name. The remaining
-     * sub-keys are wiped through prefs_ai_remove_section(). */
-    return _ai_remove_string(provider, "url");
-}
-
-char*
-prefs_ai_get_provider_url(const char* const provider)
-{
-    return _ai_get_string(provider, "url");
-}
-
-gboolean
-prefs_ai_remove_section(const char* const provider)
-{
-    if (!provider || !prefs)
-        return FALSE;
-
-    auto_gchar gchar* group = _ai_section(provider);
-    if (!g_key_file_has_group(prefs, group))
-        return FALSE;
-
-    g_key_file_remove_group(prefs, group, NULL);
-    _save_prefs();
-    return TRUE;
-}
-
-GList*
-prefs_ai_list_providers(void)
-{
-    if (!prefs)
-        return NULL;
-
-    GList* result = NULL;
-    gsize len = 0;
-    auto_gcharv gchar** groups = g_key_file_get_groups(prefs, &len);
-    if (!groups)
-        return NULL;
-
-    gsize prefix_len = strlen(PREF_GROUP_AI_PREFIX);
-    for (gsize i = 0; i < len; i++) {
-        const gchar* g = groups[i];
-        if (g_str_has_prefix(g, PREF_GROUP_AI_PREFIX) && strlen(g) > prefix_len) {
-            /* Only count groups that actually identify a provider (have url). */
-            if (g_key_file_has_key(prefs, g, "url", NULL)) {
-                result = g_list_append(result, g_strdup(g + prefix_len));
-            }
-        }
-    }
-
-    return result;
-}
-
-void
-prefs_free_ai_providers(GList* providers)
-{
-    if (providers) {
-        g_list_free_full(providers, g_free);
-    }
-}
-
-GList*
-prefs_ai_get_providers(void)
-{
-    GList* configured = prefs_ai_list_providers();
-    GList* result = NULL;
-
-    for (GList* curr = configured; curr; curr = g_list_next(curr)) {
-        const gchar* name = (const gchar*)curr->data;
-        auto_gchar gchar* url = prefs_ai_get_provider_url(name);
-        if (url && strlen(url) > 0) {
-            result = g_list_append(result, g_strdup(name));
-            result = g_list_append(result, g_strdup(url));
-        }
-    }
-    prefs_free_ai_providers(configured);
-
-    /* Seed openai/perplexity into the in-memory result on very first init
-     * only. In production the "defaults_initialized" sentinel in [ai] is what
-     * tells us we've already seeded — a user who removes every provider must
-     * not get them silently re-added on the next start. When prefs is NULL
-     * (e.g. unit tests that bring up ai_client without prefs_load) we still
-     * seed the in-memory list so behaviour matches a fresh first run, but
-     * skip the persistence write. */
-    gboolean already_seeded = prefs && g_key_file_get_boolean(prefs, PREF_GROUP_AI, "defaults_initialized", NULL);
-    if (!already_seeded && !result) {
-        if (prefs) {
-            prefs_ai_set_provider("openai", "https://api.openai.com/");
-            prefs_ai_set_provider("perplexity", "https://api.perplexity.ai/");
-        }
-        result = g_list_append(result, g_strdup("openai"));
-        result = g_list_append(result, g_strdup("https://api.openai.com/"));
-        result = g_list_append(result, g_strdup("perplexity"));
-        result = g_list_append(result, g_strdup("https://api.perplexity.ai/"));
-    }
-    if (prefs && !already_seeded) {
-        g_key_file_set_boolean(prefs, PREF_GROUP_AI, "defaults_initialized", TRUE);
-        _save_prefs();
-    }
-
-    return result;
-}
-
-/* --- Custom per-provider settings (setting.<name>) --- */
-
-gboolean
-prefs_ai_set_setting(const char* const provider, const char* const setting, const char* const value)
-{
-    if (!provider || !setting)
-        return FALSE;
-    auto_gchar gchar* key = g_strconcat(PREF_AI_SETTING_PREFIX, setting, NULL);
-    if (!value)
-        return _ai_remove_string(provider, key);
-    return _ai_set_string(provider, key, value);
-}
-
-gboolean
-prefs_ai_remove_setting(const char* const provider, const char* const setting)
-{
-    if (!provider || !setting)
-        return FALSE;
-    auto_gchar gchar* key = g_strconcat(PREF_AI_SETTING_PREFIX, setting, NULL);
-    return _ai_remove_string(provider, key);
-}
-
-char*
-prefs_ai_get_setting(const char* const provider, const char* const setting)
-{
-    if (!provider || !setting)
-        return NULL;
-    auto_gchar gchar* key = g_strconcat(PREF_AI_SETTING_PREFIX, setting, NULL);
-    return _ai_get_string(provider, key);
-}
-
-GList*
-prefs_ai_list_settings(const char* const provider)
-{
-    if (!provider || !prefs)
-        return NULL;
-
-    auto_gchar gchar* group = _ai_section(provider);
-    if (!g_key_file_has_group(prefs, group))
-        return NULL;
-
-    GList* result = NULL;
-    gsize len = 0;
-    auto_gcharv gchar** keys = g_key_file_get_keys(prefs, group, &len, NULL);
-    gsize prefix_len = strlen(PREF_AI_SETTING_PREFIX);
-    for (gsize i = 0; i < len; i++) {
-        if (g_str_has_prefix(keys[i], PREF_AI_SETTING_PREFIX) && strlen(keys[i]) > prefix_len) {
-            result = g_list_append(result, g_strdup(keys[i] + prefix_len));
-        }
-    }
-    return result;
-}
-
-void
-prefs_free_ai_settings(GList* settings)
-{
-    if (settings) {
-        g_list_free_full(settings, g_free);
-    }
-}
-
 // get the preference group for a specific preference
 // for example the PREF_BEEP setting ("beep" in .profrc, see _get_key) belongs
 // to the [ui] section.

src/config/preferences.h

@@ -366,35 +366,10 @@ char* prefs_ai_get_token(const char* const provider);
 GList* prefs_ai_list_tokens(void);
 void prefs_free_ai_tokens(GList* tokens);
 
-/* AI provider management */
-gboolean prefs_ai_set_provider(const char* const provider, const char* const url);
-gboolean prefs_ai_remove_provider(const char* const provider);
-char* prefs_ai_get_provider_url(const char* const provider);
-GList* prefs_ai_list_providers(void);
-void prefs_free_ai_providers(GList* providers);
-GList* prefs_ai_get_providers(void);
-
-/* Wipe the whole [ai/<provider>] subsection (url, key, models, default_model,
- * custom settings) in one call. */
-gboolean prefs_ai_remove_section(const char* const provider);
-
 /* AI model cache management */
 gboolean prefs_ai_set_models(const char* const provider, const gchar* const* models, gint count);
 gboolean prefs_ai_remove_models(const char* const provider);
 GList* prefs_ai_get_models(const char* const provider);
 void prefs_free_ai_models(GList* models);
 
-/* AI default model per provider */
-gboolean prefs_ai_set_default_model(const char* const provider, const char* const model);
-gboolean prefs_ai_remove_default_model(const char* const provider);
-char* prefs_ai_get_default_model(const char* const provider);
-
-/* AI per-provider custom settings (e.g. tools, search) — persisted as
- * setting.<name>=<value> inside [ai/<provider>]. Pass NULL value to remove. */
-gboolean prefs_ai_set_setting(const char* const provider, const char* const setting, const char* const value);
-gboolean prefs_ai_remove_setting(const char* const provider, const char* const setting);
-char* prefs_ai_get_setting(const char* const provider, const char* const setting);
-GList* prefs_ai_list_settings(const char* const provider);
-void prefs_free_ai_settings(GList* settings);
-
 #endif

src/database_flatfile_verify.c

@@ -211,13 +211,9 @@ _first_pass(FILE* fp, const char* basename,
 
         if (pl->stanza_id && pl->stanza_id[0] != '\0') {
             if (g_hash_table_contains(seen_stanza_ids, pl->stanza_id)) {
-                // Older clients (Pidgin, Adium, even early Profanity)
-                // sometimes reuse client-generated stanza-ids across
-                // distinct messages, so a collision is not a real
-                // integrity defect — log it for diagnostics but don't
-                // surface it through /history verify.
-                log_debug("flatfile verify: duplicate stanza-id \"%s\" at %s:%d",
-                          pl->stanza_id, basename, lineno);
+                *issues = g_slist_prepend(*issues,
+                                          _issue_new(INTEGRITY_WARNING, basename, lineno,
+                                                     g_strdup_printf("Duplicate stanza-id \"%s\"", pl->stanza_id)));
             } else {
                 g_hash_table_insert(seen_stanza_ids, g_strdup(pl->stanza_id), GINT_TO_POINTER(lineno));
             }
@@ -306,13 +302,7 @@ _verify_contact_dir(const char* cdir_path, GSList** issues)
         return;
     }
 
-    // Reconstruct the contact JID from the directory name so issue reports
-    // identify which contact the problem belongs to (every contact has its
-    // own history.log, so the bare filename is ambiguous).
-    auto_gchar gchar* dir_name = g_path_get_basename(cdir_path);
-    auto_gcharv gchar** parts = g_strsplit(dir_name, "_at_", -1);
-    auto_gchar gchar* contact_jid = g_strjoinv("@", parts);
-    auto_gchar gchar* basename = g_strdup_printf("%s/history.log", contact_jid);
+    const char* basename = "history.log";
 
     _check_permissions(filepath, basename, issues);
 

src/database_sqlite.c

@@ -466,36 +466,23 @@ _sqlite_verify_integrity(const gchar* const contact_barejid)
         sqlite3_finalize(stmt);
     }
 
-    // Check timestamp ordering, restricted to consecutive rows belonging
-    // to the same conversation pair so adjacency does not span unrelated
-    // contacts. Adjacent rows by id from different conversations are
-    // legitimately out-of-order and should not be reported.
+    // Check timestamp ordering for a specific contact or all
     const Jid* myjid = connection_get_jid();
     if (myjid && myjid->barejid) {
         auto_sqlite char* query = NULL;
         if (contact_barejid) {
             query = sqlite3_mprintf(
-                "SELECT A.`id`, A.`timestamp`, A.`from_jid`, A.`to_jid`, B.`id`, B.`timestamp` "
-                "FROM `ChatLogs` A "
-                "JOIN `ChatLogs` B ON B.`from_jid` = A.`from_jid` AND B.`to_jid` = A.`to_jid` "
-                "                  AND B.`id` > A.`id` "
+                "SELECT A.`id`, A.`timestamp`, B.`id`, B.`timestamp` FROM `ChatLogs` A "
+                "JOIN `ChatLogs` B ON B.`id` = A.`id` + 1 "
                 "WHERE A.`timestamp` > B.`timestamp` "
                 "AND ((A.`from_jid` = %Q AND A.`to_jid` = %Q) OR (A.`from_jid` = %Q AND A.`to_jid` = %Q)) "
-                "AND NOT EXISTS (SELECT 1 FROM `ChatLogs` C "
-                "                WHERE C.`from_jid` = A.`from_jid` AND C.`to_jid` = A.`to_jid` "
-                "                AND C.`id` > A.`id` AND C.`id` < B.`id`) "
                 "LIMIT 50",
                 contact_barejid, myjid->barejid, myjid->barejid, contact_barejid);
         } else {
             query = sqlite3_mprintf(
-                "SELECT A.`id`, A.`timestamp`, A.`from_jid`, A.`to_jid`, B.`id`, B.`timestamp` "
-                "FROM `ChatLogs` A "
-                "JOIN `ChatLogs` B ON B.`from_jid` = A.`from_jid` AND B.`to_jid` = A.`to_jid` "
-                "                  AND B.`id` > A.`id` "
+                "SELECT A.`id`, A.`timestamp`, B.`id`, B.`timestamp` FROM `ChatLogs` A "
+                "JOIN `ChatLogs` B ON B.`id` = A.`id` + 1 "
                 "WHERE A.`timestamp` > B.`timestamp` "
-                "AND NOT EXISTS (SELECT 1 FROM `ChatLogs` C "
-                "                WHERE C.`from_jid` = A.`from_jid` AND C.`to_jid` = A.`to_jid` "
-                "                AND C.`id` > A.`id` AND C.`id` < B.`id`) "
                 "LIMIT 50");
         }
 
@@ -503,19 +490,15 @@ _sqlite_verify_integrity(const gchar* const contact_barejid)
             while (sqlite3_step(stmt) == SQLITE_ROW) {
                 int id_a = sqlite3_column_int(stmt, 0);
                 const char* ts_a = (const char*)sqlite3_column_text(stmt, 1);
-                const char* from_a = (const char*)sqlite3_column_text(stmt, 2);
-                const char* to_a = (const char*)sqlite3_column_text(stmt, 3);
-                int id_b = sqlite3_column_int(stmt, 4);
-                const char* ts_b = (const char*)sqlite3_column_text(stmt, 5);
+                int id_b = sqlite3_column_int(stmt, 2);
+                const char* ts_b = (const char*)sqlite3_column_text(stmt, 3);
 
                 integrity_issue_t* issue = g_malloc0(sizeof(integrity_issue_t));
                 issue->level = INTEGRITY_WARNING;
-                issue->file = g_strdup_printf("%s↔%s/chatlog.db",
-                                              from_a ? from_a : "?", to_a ? to_a : "?");
+                issue->file = g_strdup("chatlog.db");
                 issue->line = id_a;
                 issue->message = g_strdup_printf("Timestamp out of order: row %d (%s) > row %d (%s)",
-                                                 id_a, ts_a ? ts_a : "NULL",
-                                                 id_b, ts_b ? ts_b : "NULL");
+                                                 id_a, ts_a ? ts_a : "NULL", id_b, ts_b ? ts_b : "NULL");
                 issues = g_slist_append(issues, issue);
             }
             sqlite3_finalize(stmt);
@@ -523,7 +506,7 @@ _sqlite_verify_integrity(const gchar* const contact_barejid)
 
         // Check broken LMC references
         auto_sqlite char* lmc_query = sqlite3_mprintf(
-            "SELECT A.`id`, A.`replaces_db_id`, A.`from_jid`, A.`to_jid` FROM `ChatLogs` A "
+            "SELECT A.`id`, A.`replaces_db_id` FROM `ChatLogs` A "
             "WHERE A.`replaces_db_id` IS NOT NULL "
             "AND NOT EXISTS (SELECT 1 FROM `ChatLogs` B WHERE B.`id` = A.`replaces_db_id`) "
             "LIMIT 50");
@@ -532,13 +515,10 @@ _sqlite_verify_integrity(const gchar* const contact_barejid)
             while (sqlite3_step(stmt) == SQLITE_ROW) {
                 int id = sqlite3_column_int(stmt, 0);
                 int replaces_id = sqlite3_column_int(stmt, 1);
-                const char* from = (const char*)sqlite3_column_text(stmt, 2);
-                const char* to = (const char*)sqlite3_column_text(stmt, 3);
 
                 integrity_issue_t* issue = g_malloc0(sizeof(integrity_issue_t));
                 issue->level = INTEGRITY_ERROR;
-                issue->file = g_strdup_printf("%s↔%s/chatlog.db",
-                                              from ? from : "?", to ? to : "?");
+                issue->file = g_strdup("chatlog.db");
                 issue->line = id;
                 issue->message = g_strdup_printf("Broken LMC reference: row %d references non-existent row %d",
                                                  id, replaces_id);

src/tools/autocomplete.c

@@ -260,7 +260,7 @@ autocomplete_complete(Autocomplete ac, const gchar* search_str, gboolean quote,
             FREE_SET_NULL(ac->search_str);
         }
 
-        ac->search_str = g_strdup(search_str);
+        ac->search_str = strdup(search_str);
         found = _search(ac, ac->items, quote, NEXT);
 
         return found;
@@ -305,7 +305,7 @@ autocomplete_complete(Autocomplete ac, const gchar* search_str, gboolean quote,
 // autocomplete_func func is used -> autocomplete_param_with_func
 // Autocomplete ac, gboolean quote are used -> autocomplete_param_with_ac
 static char*
-_autocomplete_param_common(const char* const input, const char* command, autocomplete_func func, Autocomplete ac, gboolean quote, gboolean previous, void* context)
+_autocomplete_param_common(const char* const input, char* command, autocomplete_func func, Autocomplete ac, gboolean quote, gboolean previous, void* context)
 {
     int len;
     auto_gchar gchar* command_cpy = g_strdup_printf("%s ", command);
@@ -344,7 +344,7 @@ _autocomplete_param_common(const char* const input, const char* command, autocom
 }
 
 char*
-autocomplete_param_with_func(const char* const input, const char* command, autocomplete_func func, gboolean previous, void* context)
+autocomplete_param_with_func(const char* const input, char* command, autocomplete_func func, gboolean previous, void* context)
 {
     return _autocomplete_param_common(input, command, func, NULL, FALSE, previous, context);
 }

src/tools/autocomplete.h

@@ -63,7 +63,7 @@ gchar* autocomplete_complete(Autocomplete ac, const gchar* search_str, gboolean
 GList* autocomplete_create_list(Autocomplete ac);
 gint autocomplete_length(Autocomplete ac);
 
-char* autocomplete_param_with_func(const char* const input, const char* command,
+char* autocomplete_param_with_func(const char* const input, char* command,
                                    autocomplete_func func, gboolean previous, void* context);
 
 char* autocomplete_param_with_ac(const char* const input, char* command,

src/ui/window.c

@@ -848,14 +848,6 @@ win_page_down(ProfWin* window, int scroll_size)
         window->layout->paged = 0;
         window->layout->unread_msg = 0;
     }
-
-    // Non-chat windows have no DB to fetch from, so WIN_SCROLL_REACHED_BOTTOM
-    // never fires; reset paged once the buffer's last line is on screen.
-    if (window->type != WIN_CHAT
-        && (total_rows - *page_start) <= page_space + 1) {
-        window->layout->paged = 0;
-        window->layout->unread_msg = 0;
-    }
 }
 
 void

src/ui/window_list.c

@@ -867,6 +867,24 @@ wins_get_prune_wins(void)
     return result;
 }
 
+ProfAiWin*
+wins_get_ai(void)
+{
+    GList* curr = values;
+
+    while (curr) {
+        ProfWin* window = curr->data;
+        if (window->type == WIN_AI) {
+            ProfAiWin* aiwin = (ProfAiWin*)window;
+            assert(aiwin->memcheck == PROFAIWIN_MEMCHECK);
+            return aiwin;
+        }
+        curr = g_list_next(curr);
+    }
+
+    return NULL;
+}
+
 gboolean
 wins_ai_exists(ProfAiWin* const aiwin)
 {

src/ui/window_list.h

@@ -63,6 +63,7 @@ ProfPrivateWin* wins_get_private(const char* const fulljid);
 ProfPluginWin* wins_get_plugin(const char* const tag);
 ProfXMLWin* wins_get_xmlconsole(void);
 ProfVcardWin* wins_get_vcard(void);
+ProfAiWin* wins_get_ai(void);
 gboolean wins_ai_exists(ProfAiWin* const aiwin);
 
 void wins_close_plugin(char* tag);

tests/functionaltests/ai_http_stub.c

@@ -0,0 +1,100 @@
+/*
+ * ai_http_stub.c
+ *
+ * Spawns tests/functionaltests/ai_http_stub.py as a child process for
+ * functional tests that exercise the AI client's HTTP code path. The
+ * stub listens on 127.0.0.1 on an OS-chosen port and prints "PORT=<n>"
+ * as its first line; we read it back and hand the port to the caller.
+ */
+
+#include "ai_http_stub.h"
+
+#include <errno.h>
+#include <fcntl.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/wait.h>
+#include <unistd.h>
+
+#define STUB_SCRIPT "../tests/functionaltests/ai_http_stub.py"
+#define READLINE_MAX 64
+
+static pid_t stub_pid = 0;
+
+int
+ai_http_stub_start(const char* mode, const char* reply)
+{
+    int pipefd[2];
+    if (pipe(pipefd) != 0) {
+        return 0;
+    }
+
+    pid_t pid = fork();
+    if (pid < 0) {
+        close(pipefd[0]);
+        close(pipefd[1]);
+        return 0;
+    }
+
+    if (pid == 0) {
+        /* Child: redirect stdout to the pipe write end, then exec the stub. */
+        close(pipefd[0]);
+        dup2(pipefd[1], STDOUT_FILENO);
+        close(pipefd[1]);
+
+        if (mode) {
+            setenv("AI_STUB_MODE", mode, 1);
+        }
+        if (reply) {
+            setenv("AI_STUB_REPLY", reply, 1);
+        }
+        /* Argument "0" -> let the OS pick a free port. */
+        execlp("python3", "python3", STUB_SCRIPT, "0", (char*)NULL);
+        /* Falls through on exec failure. */
+        _exit(127);
+    }
+
+    /* Parent: read "PORT=<n>\n" from the child's stdout. */
+    close(pipefd[1]);
+
+    char buf[READLINE_MAX] = { 0 };
+    ssize_t total = 0;
+    while (total < (ssize_t)sizeof(buf) - 1) {
+        ssize_t n = read(pipefd[0], buf + total, sizeof(buf) - 1 - total);
+        if (n <= 0) {
+            break;
+        }
+        total += n;
+        if (memchr(buf, '\n', total)) {
+            break;
+        }
+    }
+    close(pipefd[0]);
+
+    int port = 0;
+    if (sscanf(buf, "PORT=%d", &port) != 1 || port <= 0) {
+        kill(pid, SIGTERM);
+        waitpid(pid, NULL, 0);
+        return 0;
+    }
+
+    stub_pid = pid;
+    return port;
+}
+
+void
+ai_http_stub_stop(void)
+{
+    if (stub_pid <= 0) {
+        return;
+    }
+    kill(stub_pid, SIGTERM);
+    /* Give the stub a moment to exit cleanly, then reap. */
+    int status = 0;
+    pid_t waited = waitpid(stub_pid, &status, 0);
+    (void)waited;
+    (void)status;
+    stub_pid = 0;
+}

tests/functionaltests/ai_http_stub.h

@@ -0,0 +1,25 @@
+#ifndef __H_AI_HTTP_STUB
+#define __H_AI_HTTP_STUB
+
+#include <sys/types.h>
+
+/*
+ * Spawn the Python AI stub script (tests/functionaltests/ai_http_stub.py).
+ *
+ * mode      — one of "ok", "openai", "401", "500", "models" (see the stub
+ *             script). Selects the response body and HTTP status.
+ * reply     — body text used by "ok"/"openai"/"401" modes. Pass NULL for
+ *             the default ("MOCK-REPLY").
+ *
+ * Returns the listening port (>0) on success, 0 on failure. The child's
+ * pid is recorded internally; call ai_http_stub_stop() to terminate it.
+ */
+int ai_http_stub_start(const char* mode, const char* reply);
+
+/*
+ * Send SIGTERM to the most recently spawned stub and reap it.
+ * No-op if no stub is running.
+ */
+void ai_http_stub_stop(void);
+
+#endif

tests/functionaltests/ai_http_stub.py

@@ -0,0 +1,117 @@
+#!/usr/bin/env python3
+"""
+Minimal HTTP stub for AI functional tests.
+
+Listens on 127.0.0.1:<port> and serves canned JSON responses for any POST.
+Behaviour is selected via the URL path and the AI_STUB_MODE environment
+variable, set by the test runner before exec().
+
+Modes:
+  - "ok"     : 200 with a valid OpenAI Responses-API body
+                ({"output":[{"content":[{"text":"...","type":"output_text"}]}]})
+  - "openai" : 200 with a legacy OpenAI Chat Completions body
+                ({"choices":[{"message":{"content":"..."}}]})
+  - "401"    : 401 with an OpenAI-style error envelope
+  - "500"    : 500 with a body that triggers the parse-error fallback
+  - "models" : 200 with a /v1/models list body
+
+The reply text is taken from AI_STUB_REPLY (default: "MOCK-REPLY").
+
+The stub writes its actual listening port to stdout as a single line
+"PORT=<n>" so the parent can read it back, then runs until SIGTERM.
+"""
+import json
+import os
+import sys
+from http.server import HTTPServer, BaseHTTPRequestHandler
+
+
+REPLY = os.environ.get("AI_STUB_REPLY", "MOCK-REPLY")
+MODE = os.environ.get("AI_STUB_MODE", "ok")
+
+
+def _dumps(body: object) -> bytes:
+    """Produce compact JSON without whitespace — profanity's hand-rolled
+    parser does strstr for `"key":"`, which fails when json.dumps inserts
+    a space after the colon by default."""
+    return json.dumps(body, separators=(",", ":")).encode("utf-8")
+
+
+def _body_for(mode: str) -> tuple[int, bytes]:
+    if mode == "ok":
+        body = {
+            "output": [
+                {
+                    "content": [
+                        {"text": REPLY, "type": "output_text"}
+                    ]
+                }
+            ]
+        }
+        return 200, _dumps(body)
+    if mode == "openai":
+        body = {
+            "choices": [
+                {"message": {"role": "assistant", "content": REPLY}}
+            ]
+        }
+        return 200, _dumps(body)
+    if mode == "401":
+        body = {
+            "error": {
+                "message": REPLY,
+                "type": "invalid_request_error",
+                "code": "invalid_api_key",
+            }
+        }
+        return 401, _dumps(body)
+    if mode == "500":
+        return 500, b"<html><body>Internal Server Error</body></html>"
+    if mode == "models":
+        body = {
+            "object": "list",
+            "data": [
+                {"id": "model-a", "object": "model"},
+                {"id": "model-b", "object": "model"},
+                {"id": "model-c", "object": "model"},
+            ],
+        }
+        return 200, _dumps(body)
+    return 200, b"{}"
+
+
+class StubHandler(BaseHTTPRequestHandler):
+    def _send(self):
+        status, body = _body_for(MODE)
+        self.send_response(status)
+        self.send_header("Content-Type", "application/json")
+        self.send_header("Content-Length", str(len(body)))
+        self.end_headers()
+        self.wfile.write(body)
+
+    def do_POST(self):
+        length = int(self.headers.get("Content-Length", 0))
+        if length:
+            self.rfile.read(length)
+        self._send()
+
+    def do_GET(self):
+        self._send()
+
+    def log_message(self, fmt, *args):
+        return
+
+
+def main() -> None:
+    port = int(sys.argv[1]) if len(sys.argv) > 1 else 0
+    srv = HTTPServer(("127.0.0.1", port), StubHandler)
+    actual = srv.server_address[1]
+    print(f"PORT={actual}", flush=True)
+    try:
+        srv.serve_forever()
+    except KeyboardInterrupt:
+        pass
+
+
+if __name__ == "__main__":
+    main()

tests/functionaltests/functionaltests.c

@@ -60,6 +60,7 @@
 #include "test_export_import.h"
 #endif
 #include "test_ai.h"
+#include "test_ai_http.h"
 
 /* Macro to wrap each test with setup/teardown functions */
 #define PROF_FUNC_TEST(test)                                \
@@ -324,7 +325,7 @@ main(int argc, char* argv[])
      * prof_connect() calls.
      * ============================================================ */
     const struct CMUnitTest group5_tests[] = {
-        /* Console-only — no network calls */
+        /* Tier A — no network calls */
         PROF_FUNC_TEST_AI(ai_no_args_shows_help),
         PROF_FUNC_TEST_AI(ai_providers_lists_defaults),
         PROF_FUNC_TEST_AI(ai_providers_list_shows_key_status),
@@ -336,9 +337,17 @@ main(int argc, char* argv[])
         PROF_FUNC_TEST_AI(ai_clear_without_window_errors),
         PROF_FUNC_TEST_AI(ai_remove_provider_works),
         PROF_FUNC_TEST_AI(ai_remove_provider_unknown_errors),
+        PROF_FUNC_TEST_AI(ai_set_default_provider_unknown_errors),
         PROF_FUNC_TEST_AI(ai_set_default_model_updates_provider),
         PROF_FUNC_TEST_AI(ai_switch_without_window_errors),
         PROF_FUNC_TEST_AI(ai_bad_subcommand_shows_usage),
+
+        /* Tier B — full request/response through Python HTTP stub */
+        PROF_FUNC_TEST_AI(ai_http_prompt_returns_ok),
+        PROF_FUNC_TEST_AI(ai_http_prompt_openai_format),
+        PROF_FUNC_TEST_AI(ai_http_prompt_401_shows_error),
+        PROF_FUNC_TEST_AI(ai_http_prompt_500_surfaced),
+        PROF_FUNC_TEST_AI(ai_http_models_fetch_lists_models),
     };
 
     /* Test group registry for easy extension */
@@ -352,7 +361,7 @@ main(int argc, char* argv[])
         { "Group 2: ExportImport/Receipts", group2_tests, ARRAY_SIZE(group2_tests) },
         { "Group 3: Presence/Disconnect/DBHistory/Message/MUC-DB", group3_tests, ARRAY_SIZE(group3_tests) },
         { "Group 4: Session/MUC/Carbons/MigrationStress", group4_tests, ARRAY_SIZE(group4_tests) },
-        { "Group 5: AI command surface (console only)", group5_tests, ARRAY_SIZE(group5_tests) },
+        { "Group 5: AI command surface (Tier A + Tier B)", group5_tests, ARRAY_SIZE(group5_tests) },
     };
     const int num_groups = ARRAY_SIZE(groups);
 

tests/functionaltests/test_ai.c

@@ -38,16 +38,14 @@ ai_init_test(void** state)
 void
 ai_no_args_shows_help(void** state)
 {
-    /* `/ai` with no arguments lists the built-in providers and a usage hint.
-     * We don't pin specific provider names — defaults may change. Verify the
-     * header, the "Configured providers" section, that *some* provider line
-     * carries an http(s) URL, and the usage hint. */
+    /* `/ai` with no arguments lists the built-in providers and a usage hint. */
     prof_input("/ai");
 
     prof_timeout(5);
     assert_true(prof_output_exact("AI Chat - OpenAI-compatible API client"));
     assert_true(prof_output_exact("Configured providers:"));
-    assert_true(prof_output_regex("URL: https?://"));
+    assert_true(prof_output_regex("openai"));
+    assert_true(prof_output_regex("perplexity"));
     assert_true(prof_output_regex("Use '/ai start' to begin a chat"));
     prof_timeout_reset();
 }
@@ -60,8 +58,8 @@ ai_providers_lists_defaults(void** state)
 
     prof_timeout(5);
     assert_true(prof_output_exact("Available AI providers:"));
-    /* At least one URL line is rendered — exact name agnostic. */
-    assert_true(prof_output_regex("https?://"));
+    assert_true(prof_output_regex("openai"));
+    assert_true(prof_output_regex("perplexity"));
     prof_timeout_reset();
 }
 
@@ -99,21 +97,17 @@ ai_set_provider_adds_custom(void** state)
 void
 ai_set_token_marks_key_set(void** state)
 {
-    /* Use a self-set-up provider so the test doesn't pin a default name. */
-    prof_input("/ai set provider testprov https://example.test/");
-    prof_timeout(5);
-    assert_true(prof_output_regex("Provider 'testprov' configured"));
-    prof_timeout_reset();
-
-    prof_input("/ai set token testprov sk-fake-test-key");
+    /* Setting a token must flip the provider's key status to "configured". */
+    prof_input("/ai set token openai sk-fake-test-key");
 
     prof_timeout(5);
-    assert_true(prof_output_regex("API token set for provider: testprov"));
+    assert_true(prof_output_regex("API token set for provider: openai"));
     prof_timeout_reset();
 
     prof_input("/ai providers list");
 
     prof_timeout(5);
+    /* openai now shows "Key: configured" while perplexity stays unconfigured. */
     assert_true(prof_output_regex("Key: configured"));
     prof_timeout_reset();
 }
@@ -132,52 +126,42 @@ ai_start_unknown_provider_errors(void** state)
 void
 ai_start_without_key_errors(void** state)
 {
-    /* Self-set-up provider with no token. /ai start must refuse. */
-    prof_input("/ai set provider testprov https://example.test/");
-    prof_timeout(5);
-    assert_true(prof_output_regex("Provider 'testprov' configured"));
-    prof_timeout_reset();
-
-    prof_input("/ai start testprov model-x");
+    /* Known provider without an API key should refuse to start. */
+    prof_input("/ai start openai gpt-4");
 
     prof_timeout(5);
-    assert_true(prof_output_regex("No API key set for provider 'testprov'"));
+    assert_true(prof_output_regex("No API key set for provider 'openai'"));
     prof_timeout_reset();
 }
 
 void
 ai_start_with_key_opens_window(void** state)
 {
-    /* Self-set-up provider with token; /ai start opens a WIN_AI window. */
-    prof_input("/ai set provider testprov https://example.test/");
+    /* With a token set, /ai start should create a WIN_AI window. */
+    prof_input("/ai set token openai sk-fake-test-key");
+
     prof_timeout(5);
-    assert_true(prof_output_regex("Provider 'testprov' configured"));
+    assert_true(prof_output_regex("API token set for provider: openai"));
     prof_timeout_reset();
 
-    prof_input("/ai set token testprov sk-fake-test-key");
+    prof_input("/ai start openai gpt-4");
 
     prof_timeout(5);
-    assert_true(prof_output_regex("API token set for provider: testprov"));
-    prof_timeout_reset();
-
-    prof_input("/ai start testprov model-x");
-
-    prof_timeout(5);
-    /* /ai start switches focus to the new WIN_AI window; the window prints
-     * "AI Chat: <provider>/<model>" as its first line. */
-    assert_true(prof_output_regex("AI Chat: testprov/model-x"));
+    /* /ai start switches focus to the new WIN_AI window; cons_show output
+     * to the console is therefore not the right place to look. The window
+     * itself prints "AI Chat: <provider>/<model>" as its first line. */
+    assert_true(prof_output_regex("AI Chat: openai/gpt-4"));
     prof_timeout_reset();
 }
 
 void
 ai_clear_without_window_errors(void** state)
 {
-    /* /ai clear from the console (no active AI window) refuses with the
-     * shared "must be in AI chat window" guard used by /ai switch as well. */
+    /* /ai clear from the console (no active AI window) should report nicely. */
     prof_input("/ai clear");
 
     prof_timeout(5);
-    assert_true(prof_output_regex("Must be in an AI chat window"));
+    assert_true(prof_output_regex("No active AI chat window to clear"));
     prof_timeout_reset();
 }
 
@@ -212,31 +196,36 @@ ai_remove_provider_unknown_errors(void** state)
     prof_timeout_reset();
 }
 
+void
+ai_set_default_provider_unknown_errors(void** state)
+{
+    /* Setting an unknown default provider should error, not silently accept. */
+    prof_input("/ai set default-provider does_not_exist");
+
+    prof_timeout(5);
+    assert_true(prof_output_regex("Provider 'does_not_exist' not found"));
+    prof_timeout_reset();
+}
+
 void
 ai_set_default_model_updates_provider(void** state)
 {
     /* Setting a default model is acknowledged on the console. */
-    prof_input("/ai set provider testprov https://example.test/");
-    prof_timeout(5);
-    assert_true(prof_output_regex("Provider 'testprov' configured"));
-    prof_timeout_reset();
-
-    prof_input("/ai set default-model testprov model-preview");
+    prof_input("/ai set default-model openai gpt-5-preview");
 
     prof_timeout(5);
-    assert_true(prof_output_regex("Default model for provider 'testprov' set to: model-preview"));
+    assert_true(prof_output_regex("Default model for provider 'openai' set to: gpt-5-preview"));
     prof_timeout_reset();
 }
 
 void
 ai_switch_without_window_errors(void** state)
-{
-    /* /ai switch with no active AI window refuses with the shared
-     * "must be in AI chat window" guard. */
-    prof_input("/ai switch testprov model-x");
+{   
+    /* /ai switch with no active AI window should produce an actionable error. */
+    prof_input("/ai switch openai gpt-4");
 
     prof_timeout(5);
-    assert_true(prof_output_regex("Must be in an AI chat window"));
+    assert_true(prof_output_regex("No active AI chat window"));
     prof_timeout_reset();
 }
 

tests/functionaltests/test_ai.h

@@ -20,6 +20,7 @@ void ai_start_with_key_opens_window(void** state);
 void ai_clear_without_window_errors(void** state);
 void ai_remove_provider_works(void** state);
 void ai_remove_provider_unknown_errors(void** state);
+void ai_set_default_provider_unknown_errors(void** state);
 void ai_set_default_model_updates_provider(void** state);
 void ai_switch_without_window_errors(void** state);
 void ai_bad_subcommand_shows_usage(void** state);

tests/functionaltests/test_ai_http.c

@@ -0,0 +1,157 @@
+/*
+ * test_ai_http.c
+ *
+ * Functional tests for the /ai command surface that exercise the libcurl
+ * HTTP code path. A small Python HTTP stub (ai_http_stub.py) is spawned
+ * per-test on a free local port; profanity is configured to point at it
+ * via `/ai set provider`. The stub serves canned JSON whose shape is
+ * controlled via AI_STUB_MODE.
+ *
+ * These tests intentionally do not race the worker thread directly —
+ * they rely on prof_timeout() retries to catch the response once it
+ * propagates back through the AI window.
+ */
+
+#include <glib.h>
+#include "prof_cmocka.h"
+#include <stdlib.h>
+#include <string.h>
+
+#include "proftest.h"
+#include "ai_http_stub.h"
+
+#define WAIT_AI_RESPONSE_SEC 10
+
+/*
+ * Configure profanity to use the spawned stub as a provider named "mock"
+ * with a dummy bearer token, then issue /ai start to open the AI window.
+ * Returns the stub port on success, fails the test on stub-spawn failure.
+ */
+static int
+_setup_mock_provider(const char* mode, const char* reply)
+{
+    int port = ai_http_stub_start(mode, reply);
+    assert_int_not_equal(0, port);
+
+    char cmd[256];
+    g_snprintf(cmd, sizeof(cmd), "/ai set provider mock http://127.0.0.1:%d/", port);
+    prof_input(cmd);
+    prof_timeout(5);
+    assert_true(prof_output_regex("Provider 'mock' configured"));
+    prof_timeout_reset();
+
+    prof_input("/ai set token mock fake-test-token");
+    prof_timeout(5);
+    assert_true(prof_output_regex("API token set for provider: mock"));
+    prof_timeout_reset();
+
+    return port;
+}
+
+void
+ai_http_prompt_returns_ok(void** state)
+{
+    /* Happy path: stub returns Responses API "text" body; reply appears in window. */
+    _setup_mock_provider("ok", "STUB-HELLO");
+
+    prof_input("/ai start mock testmodel");
+    prof_timeout(5);
+    assert_true(prof_output_regex("AI Chat: mock/testmodel"));
+    prof_timeout_reset();
+
+    /* Plain text in AI window goes through cl_ev_send_ai_msg -> ai_send_prompt. */
+    prof_input("hello stub");
+
+    prof_timeout(WAIT_AI_RESPONSE_SEC);
+    assert_true(prof_output_regex("STUB-HELLO"));
+    prof_timeout_reset();
+
+    ai_http_stub_stop();
+}
+
+void
+ai_http_prompt_openai_format(void** state)
+{
+    /* Legacy OpenAI chat completions shape: "choices[].message.content". */
+    _setup_mock_provider("openai", "FROM-CHOICES");
+
+    prof_input("/ai start mock m");
+    prof_timeout(5);
+    assert_true(prof_output_regex("AI Chat: mock/m"));
+    prof_timeout_reset();
+
+    prof_input("anything");
+
+    prof_timeout(WAIT_AI_RESPONSE_SEC);
+    assert_true(prof_output_regex("FROM-CHOICES"));
+    prof_timeout_reset();
+
+    ai_http_stub_stop();
+}
+
+void
+ai_http_prompt_401_shows_error(void** state)
+{
+    /* 401 with an OpenAI-style error envelope.
+     * ai_parse_error_message() should extract the inner message; the AI
+     * window then displays "HTTP 401: <message>". */
+    _setup_mock_provider("401", "Bad token, try another");
+
+    prof_input("/ai start mock m");
+    prof_timeout(5);
+    assert_true(prof_output_regex("AI Chat: mock/m"));
+    prof_timeout_reset();
+
+    prof_input("prompt");
+
+    prof_timeout(WAIT_AI_RESPONSE_SEC);
+    /* Either the parsed message surfaces, or the raw HTTP 401 envelope. */
+    assert_true(prof_output_regex("HTTP 401") && prof_output_regex("Bad token, try another"));
+    prof_timeout_reset();
+
+    ai_http_stub_stop();
+}
+
+void
+ai_http_prompt_500_surfaced(void** state)
+{
+    /* 500 with a non-JSON HTML body. Parser falls back to raw body in HTTP error. */
+    _setup_mock_provider("500", NULL);
+
+    prof_input("/ai start mock m");
+    prof_timeout(5);
+    assert_true(prof_output_regex("AI Chat: mock/m"));
+    prof_timeout_reset();
+
+    prof_input("trigger");
+
+    prof_timeout(WAIT_AI_RESPONSE_SEC);
+    assert_true(prof_output_regex("HTTP 500"));
+    prof_timeout_reset();
+
+    ai_http_stub_stop();
+}
+
+void
+ai_http_models_fetch_lists_models(void** state)
+{
+    /* /v1/models endpoint returns a list of three models. /ai models <p>
+     * caches them silently; /ai models <p> --cached then displays the names. */
+    _setup_mock_provider("models", NULL);
+
+    prof_input("/ai models mock");
+
+    prof_timeout(WAIT_AI_RESPONSE_SEC);
+    assert_true(prof_output_regex("Cached 3 models for provider 'mock'"));
+    prof_timeout_reset();
+
+    prof_input("/ai models mock --cached");
+
+    prof_timeout(5);
+    assert_true(prof_output_regex("model-a"));
+    assert_true(prof_output_regex("model-b"));
+    assert_true(prof_output_regex("model-c"));
+    prof_timeout_reset();
+
+    ai_http_stub_stop();
+}

tests/functionaltests/test_ai_http.h

@@ -0,0 +1,10 @@
+#ifndef __H_FUNC_TEST_AI_HTTP
+#define __H_FUNC_TEST_AI_HTTP
+
+void ai_http_prompt_returns_ok(void** state);
+void ai_http_prompt_openai_format(void** state);
+void ai_http_prompt_401_shows_error(void** state);
+void ai_http_prompt_500_surfaced(void** state);
+void ai_http_models_fetch_lists_models(void** state);
+
+#endif

tests/unittests/test_ai_client.h

@@ -31,13 +31,14 @@ void test_ai_session_create_null_model_returns_null(void** state);
 void test_ai_session_api_key_null_when_no_key_set(void** state);
 /* Provider autocomplete tests */
 void test_ai_providers_find_forward(void** state);
+void test_ai_providers_find_forward_perplexity(void** state);
 void test_ai_providers_find_forward_custom(void** state);
 void test_ai_providers_find_forward_no_match(void** state);
 void test_ai_providers_find_forward_partial_match(void** state);
 void test_ai_providers_find_next(void** state);
 void test_ai_providers_find_previous(void** state);
-void test_ai_providers_find_empty_search_str(void** state);
 void test_ai_providers_find_null_search_str(void** state);
+void test_ai_providers_find_empty_search_str(void** state);
 void test_ai_providers_find_case_insensitive(void** state);
 /* Provider default model and settings tests */
 void test_ai_set_provider_default_model(void** state);
@@ -56,6 +57,8 @@ void test_ai_parse_models_escaped_quotes(void** state);
 void test_ai_parse_models_with_whitespace(void** state);
 /* AI autocomplete integration tests */
 void test_ai_start_provider_autocomplete_only_on_exact(void** state);
+void test_ai_models_find_null_session(void** state);
+void test_ai_models_find_null_provider(void** state);
 void test_ai_providers_find_cycling(void** state);
 
 /* Setup that also initializes prefs for round-trip persistence tests. */
@@ -129,12 +132,3 @@ void test_ai_parse_models_multiple_models(void** state);
 void test_ai_prefs_round_trip_api_key(void** state);
 void test_ai_prefs_round_trip_remove_key(void** state);
 void test_ai_prefs_multiple_providers_persist(void** state);
-
-/* Autocomplete deeper coverage */
-void test_ai_providers_find_after_remove_skips_removed(void** state);
-
-/* Reset hook + persistence */
-void test_ai_providers_reset_ac_restarts_cycle(void** state);
-void test_ai_add_provider_persisted_across_init(void** state);
-void test_ai_remove_provider_persisted_across_init(void** state);
-void test_ai_models_persisted_across_init(void** state);

tests/unittests/unittests.c

@@ -681,16 +681,14 @@ main(int argc, char* argv[])
         cmocka_unit_test_setup_teardown(test_ai_session_api_key_null_when_no_key_set, ai_client_setup, ai_client_teardown),
         /* Provider autocomplete tests */
         cmocka_unit_test_setup_teardown(test_ai_providers_find_forward, ai_client_setup, ai_client_teardown),
+        cmocka_unit_test_setup_teardown(test_ai_providers_find_forward_perplexity, ai_client_setup, ai_client_teardown),
         cmocka_unit_test_setup_teardown(test_ai_providers_find_forward_custom, ai_client_setup, ai_client_teardown),
         cmocka_unit_test_setup_teardown(test_ai_providers_find_forward_no_match, ai_client_setup, ai_client_teardown),
         cmocka_unit_test_setup_teardown(test_ai_providers_find_forward_partial_match, ai_client_setup, ai_client_teardown),
         cmocka_unit_test_setup_teardown(test_ai_providers_find_next, ai_client_setup, ai_client_teardown),
         cmocka_unit_test_setup_teardown(test_ai_providers_find_previous, ai_client_setup, ai_client_teardown),
+        cmocka_unit_test_setup_teardown(test_ai_providers_find_null_search_str, ai_client_setup, ai_client_teardown),
         cmocka_unit_test_setup_teardown(test_ai_providers_find_empty_search_str, ai_client_setup, ai_client_teardown),
-        /* SIGSEGV on ai_providers_find(NULL, ...) — see test body and
-         * AI_AUTOCOMPLETE_POSSIBLE_ISSUES.md, issue 1. Re-enable once the
-         * NULL-search path is guarded. */
-        /* cmocka_unit_test_setup_teardown(test_ai_providers_find_null_search_str, ai_client_setup, ai_client_teardown), */
         cmocka_unit_test_setup_teardown(test_ai_providers_find_case_insensitive, ai_client_setup, ai_client_teardown),
         /* Provider default model and settings tests */
         cmocka_unit_test_setup_teardown(test_ai_set_provider_default_model, ai_client_setup, ai_client_teardown),
@@ -709,6 +707,8 @@ main(int argc, char* argv[])
         cmocka_unit_test(test_ai_parse_models_with_whitespace),
         /* AI autocomplete integration tests */
         cmocka_unit_test_setup_teardown(test_ai_start_provider_autocomplete_only_on_exact, ai_client_setup, ai_client_teardown),
+        cmocka_unit_test_setup_teardown(test_ai_models_find_null_session, ai_client_setup, ai_client_teardown),
+        cmocka_unit_test_setup_teardown(test_ai_models_find_null_provider, ai_client_setup, ai_client_teardown),
         cmocka_unit_test_setup_teardown(test_ai_providers_find_cycling, ai_client_setup, ai_client_teardown),
         cmocka_unit_test(test_ai_json_escape),
         cmocka_unit_test(test_ai_json_escape_null),
@@ -775,13 +775,6 @@ main(int argc, char* argv[])
         cmocka_unit_test_setup_teardown(test_ai_prefs_round_trip_api_key, ai_client_setup_with_prefs, ai_client_teardown_with_prefs),
         cmocka_unit_test_setup_teardown(test_ai_prefs_round_trip_remove_key, ai_client_setup_with_prefs, ai_client_teardown_with_prefs),
         cmocka_unit_test_setup_teardown(test_ai_prefs_multiple_providers_persist, ai_client_setup_with_prefs, ai_client_teardown_with_prefs),
-        /* Autocomplete deeper coverage */
-        cmocka_unit_test_setup_teardown(test_ai_providers_find_after_remove_skips_removed, ai_client_setup, ai_client_teardown),
-        /* Reset hook + persistence */
-        cmocka_unit_test_setup_teardown(test_ai_providers_reset_ac_restarts_cycle, ai_client_setup, ai_client_teardown),
-        cmocka_unit_test_setup_teardown(test_ai_add_provider_persisted_across_init, ai_client_setup_with_prefs, ai_client_teardown_with_prefs),
-        cmocka_unit_test_setup_teardown(test_ai_remove_provider_persisted_across_init, ai_client_setup_with_prefs, ai_client_teardown_with_prefs),
-        cmocka_unit_test_setup_teardown(test_ai_models_persisted_across_init, ai_client_setup_with_prefs, ai_client_teardown_with_prefs),
         // Flatfile export/import round-trip
         cmocka_unit_test(test_ff_roundtrip_simple_chat),
         cmocka_unit_test(test_ff_roundtrip_with_all_metadata),

tests/unittests/xmpp/stub_xmpp.c

@@ -104,12 +104,6 @@ connection_create_uuid(void)
     return NULL;
 }
 
-char*
-connection_create_stanza_id(void)
-{
-    return NULL;
-}
-
 void
 connection_free_uuid(char* uuid)
 {