style(ai): rename unparseable to unparsable for codespell

fix(ai): bound response parsing and harden AUTO fallback errors
- bound _parse_responses scans to the output_text part's object and to the content array, so a later sibling item's "text" (e.g. a reasoning summary) can never be returned as the assistant reply - do not retry the other flavour on a curl timeout: the request likely reached the server and may still be generating, so a re-POST of the conversation could trigger a second billed generation - remember an unparseable 2xx from the first AUTO attempt and surface stashed first-attempt errors in both error paths, instead of showing only the final attempt's transport or HTTP error - recognize Ollama's model-not-found wording in _names_model so a model typo is not misread as a missing endpoint - drop the dead, racy provider-lookup fallback in the generic request thread: a missing provider ref is a caller bug and now fails loudly - fix ai_providers_lists_defaults to expect the header the command actually prints ("Configured providers:"); the test was broken since its introduction but CI never ran it - add functional test group 5 (AI command surface) to FUNC_TEST_GROUPS so the CI parallel target runs it; proftest.c port ranges already account for five groups
2026-07-10 12:52:44 +03:00 · 2026-07-10 12:07:34 +03:00 · 2026-07-08 20:44:02 +03:00 · 2026-07-06 16:28:36 +03:00 · 2026-07-06 16:28:36 +03:00 · 2026-07-04 14:07:22 +03:00
46 changed files with 1863 additions and 272 deletions
--- a/Makefile.am
+++ b/Makefile.am
@@ -335,7 +335,7 @@ tests_functionaltests_functionaltests_LDADD = -lcmocka -lstabber @FORKPTY_LIB@
 # Parallel functional tests target (~3x faster than sequential)
 # Usage: make check-functional-parallel
 # To add more groups: increase FUNC_TEST_GROUPS and add group in functionaltests.c
-FUNC_TEST_GROUPS = 1 2 3 4
+FUNC_TEST_GROUPS = 1 2 3 4 5

 check-functional-parallel: tests/functionaltests/functionaltests
 	@echo "Running functional tests in parallel ($(words $(FUNC_TEST_GROUPS)) groups)..."
--- a/configure.ac
+++ b/configure.ac
@@ -71,6 +71,10 @@ AC_ARG_ENABLE([omemo-qrcode],
    [AS_HELP_STRING([--enable-omemo-qrcode], [enable ability to display omemo qr code])])
 AC_ARG_ENABLE([coverage],
    [AS_HELP_STRING([--enable-coverage], [enable code coverage analysis])])
+AC_ARG_ENABLE([sanitizers],
+    [AS_HELP_STRING([--enable-sanitizers], [enable AddressSanitizer + UndefinedBehaviorSanitizer + unsigned-integer-overflow])])
+AC_ARG_ENABLE([hardening],
+    [AS_HELP_STRING([--enable-hardening], [enable extra hardening warnings (e.g. -Wnull-dereference) that may produce false positives under -O2])])

 m4_include([m4/ax_valgrind_check.m4])
 AX_VALGRIND_DFLT([drd], [off])
@@ -395,7 +399,7 @@ AC_SUBST([FORKPTY_LIB])

 ## Default parameters
 AM_CFLAGS="$AM_CFLAGS -Wall -Wextra -Wformat=2 -Wno-format-zero-length"
-AM_CFLAGS="$AM_CFLAGS -Wno-deprecated-declarations -Wno-unused-parameter -Wno-missing-field-initializers -Wno-sign-compare -Wno-cast-function-type"
+AM_CFLAGS="$AM_CFLAGS -Wno-deprecated-declarations -Wno-unused-parameter -Wno-missing-field-initializers -Wno-cast-function-type"
 AM_CFLAGS="$AM_CFLAGS -Wpointer-arith"
 AM_CFLAGS="$AM_CFLAGS -Wimplicit-function-declaration"
 AM_CFLAGS="$AM_CFLAGS -Wundef"
@@ -406,7 +410,8 @@ AM_CFLAGS="$AM_CFLAGS -std=gnu99 -ggdb3"
 # GCC-specific warnings (not supported by clang) — test each one
 saved_CFLAGS="$CFLAGS"
 for _flag in -Wlogical-op -Wduplicated-cond -Wduplicated-branches \
-             -Wstringop-overflow -Warray-bounds=2 -Walloc-zero; do
+             -Wstringop-overflow -Warray-bounds=2 -Walloc-zero \
+             -Wsign-compare; do
    AC_MSG_CHECKING([whether $CC supports $_flag])
    CFLAGS="$saved_CFLAGS $_flag -Werror"
    AC_COMPILE_IFELSE([AC_LANG_PROGRAM()],
@@ -433,11 +438,46 @@ AS_IF([test "x$enable_coverage" = xyes],
     AM_LDFLAGS="$AM_LDFLAGS --coverage"
     AC_MSG_NOTICE([Code coverage analysis enabled])])

+AS_IF([test "x$enable_sanitizers" = xyes],
+    [SAN_FLAGS="-fsanitize=address,undefined"
+     saved_CFLAGS="$CFLAGS"
+     CFLAGS="$saved_CFLAGS -fsanitize=unsigned-integer-overflow -Werror"
+     AC_MSG_CHECKING([whether $CC supports -fsanitize=unsigned-integer-overflow])
+     AC_COMPILE_IFELSE([AC_LANG_PROGRAM()],
+         [AC_MSG_RESULT([yes]); SAN_FLAGS="$SAN_FLAGS,unsigned-integer-overflow"],
+         [AC_MSG_RESULT([no])])
+     CFLAGS="$saved_CFLAGS"
+     AM_CFLAGS="$AM_CFLAGS $SAN_FLAGS -fno-sanitize-recover=all -fno-omit-frame-pointer"
+     AM_LDFLAGS="$AM_LDFLAGS -fsanitize=address,undefined"
+     AC_MSG_NOTICE([Sanitizers enabled: $SAN_FLAGS])])
+
+AS_IF([test "x$enable_hardening" = xyes],
+    [saved_CFLAGS="$CFLAGS"
+     for _flag in -Wnull-dereference; do
+         AC_MSG_CHECKING([whether $CC supports $_flag])
+         CFLAGS="$saved_CFLAGS $_flag -Werror"
+         AC_COMPILE_IFELSE([AC_LANG_PROGRAM()],
+             [AC_MSG_RESULT([yes]); AM_CFLAGS="$AM_CFLAGS $_flag"],
+             [AC_MSG_RESULT([no])])
+     done
+     CFLAGS="$saved_CFLAGS"
+     AC_MSG_NOTICE([Extra hardening warnings enabled])])
+
+# Skip _FORTIFY_SOURCE=2 if env already set one (Pikaur/makepkg) or under coverage -O0 (FORTIFY needs -O>0).
+AS_IF([test "x$enable_coverage" != xyes],
+    [AS_CASE([" ${CPPFLAGS} ${CFLAGS} "],
+        [*_FORTIFY_SOURCE=*], [AC_MSG_NOTICE([_FORTIFY_SOURCE preset from environment, leaving as-is])],
+        [AM_CFLAGS="$AM_CFLAGS -D_FORTIFY_SOURCE=2"])])
+
 AS_IF([test "x$PACKAGE_STATUS" = xdevelopment],
    [AM_CFLAGS="$AM_CFLAGS -Wunused -Werror"])
 AS_IF([test "x$PLATFORM" = xosx],
    [AM_CFLAGS="$AM_CFLAGS -Qunused-arguments"])

+# Treat glib/gio headers as system to keep their macros out of our -W* set.
+glib_CFLAGS=$(echo "$glib_CFLAGS" | sed 's/-I/-isystem /g')
+gio_CFLAGS=$(echo "$gio_CFLAGS" | sed 's/-I/-isystem /g')
+
 AM_CFLAGS="$AM_CFLAGS $PTHREAD_CFLAGS $glib_CFLAGS $gio_CFLAGS $curl_CFLAGS ${SQLITE_CFLAGS}"
 AM_CFLAGS="$AM_CFLAGS $libnotify_CFLAGS ${GTK_CFLAGS} $python_CFLAGS"
 AM_CFLAGS="$AM_CFLAGS -DTHEMES_PATH=\"\\\"$THEMES_PATH\\\"\" -DICONS_PATH=\"\\\"$ICONS_PATH\\\"\" -DGLOBAL_PYTHON_PLUGINS_PATH=\"\\\"$GLOBAL_PYTHON_PLUGINS_PATH\\\"\" -DGLOBAL_C_PLUGINS_PATH=\"\\\"$GLOBAL_C_PLUGINS_PATH\\\"\""
--- a/src/ai/ai_client.c
+++ b/src/ai/ai_client.c
--- a/src/ai/ai_client.h
+++ b/src/ai/ai_client.h
@@ -12,19 +12,38 @@ typedef struct ai_message_t
    gchar* content; /* Message content */
 } AIMessage;

+/**
+ * @brief API flavour used to talk to a provider.
+ *
+ * AUTO tries /v1/responses first and falls back to /v1/chat/completions when
+ * the endpoint is missing (404/405/501) or rejects the payload shape
+ * (400/422). The working flavour is cached for the rest of the run as a
+ * first-attempt hint (the other flavour stays available as a fallback). The
+ * other two values pin the flavour explicitly.
+ */
+typedef enum {
+    AI_API_TYPE_AUTO = 0,
+    AI_API_TYPE_RESPONSES,
+    AI_API_TYPE_CHAT_COMPLETIONS,
+} AIApiType;
+
 /**
 * @brief AI provider configuration.
 */
 typedef struct ai_provider_t
 {
-    gchar* name;           /* Provider name (e.g., "openai", "perplexity") */
-    gchar* api_url;        /* API endpoint URL */
-    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) */
-    GList* models;         /* Cached models (gchar*) */
-    gboolean models_fresh; /* Whether models cache is current */
-    gint32 ref_count;      /* Reference count (atomic) */
+    gchar* name;                   /* Provider name (e.g., "openai", "perplexity") */
+    gchar* api_url;                /* API endpoint URL */
+    gchar* project_id;             /* Optional project ID (for some providers) */
+    gchar* default_model;          /* Default model for this provider */
+    gint api_type;                 /* Configured AIApiType (atomic access; persisted) */
+    gint resolved_api_type;        /* AIApiType detected via 404 fallback (atomic access; runtime cache) */
+    gint api_epoch;                /* Bumped on URL change (atomic); a stale epoch discards resolved_api_type stamps */
+    pthread_mutex_t settings_lock; /* Protects settings and api_url (read by request threads) */
+    GHashTable* settings;          /* Extensible per-provider settings (e.g., temperature=0.7) */
+    GList* models;                 /* Cached models (gchar*) */
+    gboolean models_fresh;         /* Whether models cache is current */
+    gint32 ref_count;              /* Reference count (atomic) */
 } AIProvider;

 /**
@@ -66,7 +85,7 @@ 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
- * @return New AIProvider* (caller must unref when done)
+ * @return Borrowed AIProvider* owned by the provider table (do not unref)
 */
 AIProvider* ai_add_provider(const gchar* name, const gchar* api_url);

@@ -141,12 +160,44 @@ void ai_set_provider_default_model(const gchar* provider_name, const gchar* mode
 const gchar* ai_get_provider_default_model(const gchar* provider_name);

 /**
- * Set a custom setting for a provider.
+ * Set the API type for a provider.
 * @param provider_name The provider name
- * @param setting The setting key (e.g., "tools", "search")
- * @param value The setting value
+ * @param api_type "responses", "chat-completions", or "auto" (detect by probing)
+ * @return TRUE on success, FALSE on unknown provider or invalid type string
 */
-void ai_set_provider_setting(const gchar* provider_name, const gchar* setting, const gchar* value);
+gboolean ai_set_provider_api_type(const gchar* provider_name, const gchar* api_type);
+
+/**
+ * Get the configured API type for a provider.
+ * @param provider_name The provider name
+ * @return The configured AIApiType (AI_API_TYPE_AUTO for unknown providers)
+ */
+AIApiType ai_get_provider_api_type(const gchar* provider_name);
+
+/**
+ * Parse an API type string ("auto", "responses", "chat-completions").
+ * @param str The string to parse
+ * @param type Output for the parsed value (untouched on failure)
+ * @return TRUE if str is a valid API type
+ */
+gboolean ai_api_type_from_string(const gchar* str, AIApiType* type);
+
+/**
+ * String form of an AIApiType, e.g. for display.
+ * @param type The API type
+ * @return Static string, never NULL
+ */
+const gchar* ai_api_type_to_string(AIApiType type);
+
+/**
+ * Set a custom setting for a provider.
+ * Reserved payload keys (model, messages, input, stream) are rejected.
+ * @param provider_name The provider name
+ * @param setting The setting key (e.g., "temperature")
+ * @param value The setting value, or NULL to remove
+ * @return TRUE on success, FALSE on unknown provider or reserved key
+ */
+gboolean ai_set_provider_setting(const gchar* provider_name, const gchar* setting, const gchar* value);

 /**
 * Get a custom setting for a provider.
@@ -156,6 +207,14 @@ void ai_set_provider_setting(const gchar* provider_name, const gchar* setting, c
 */
 gchar* ai_get_provider_setting(const gchar* provider_name, const gchar* setting);

+/**
+ * List the custom setting keys currently set on a provider.
+ * @param provider_name The provider name
+ * @return GList of gchar* (free with g_list_free_full(keys, g_free)),
+ *         or NULL if the provider is unknown or has no settings
+ */
+GList* ai_get_provider_setting_keys(const gchar* provider_name);
+
 /**
 * Fetch available models from a provider's API.
 * @param provider_name The provider name
@@ -184,14 +243,25 @@ gboolean ai_models_are_fresh(const gchar* provider_name);
 void ai_parse_models_from_json(AIProvider* provider, const gchar* json);

 /**
- * Extract assistant content from an LLM response body. Tries Perplexity
- * /v1/responses "text" first, falls back to OpenAI "content". Decodes
- * the \" and \n escape sequences only.
+ * Extract assistant content from a provider response body. Detects the
+ * flavour from the envelope: chat completions
+ * ({"choices":[{"message":{"content":"..."}}]}) or responses
+ * ({"output":[{"content":[{"type":"output_text","text":"..."}]}]}).
 * @param response_json The JSON body from the provider
 * @return Newly allocated content string, or NULL if not found (caller frees)
 */
 gchar* ai_parse_response(const gchar* response_json);

+/**
+ * Extract assistant content trying the known request flavour's extractor
+ * first, then the other flavour, then a bare top-level "content" string.
+ * ai_parse_response is equivalent to passing AI_API_TYPE_AUTO.
+ * @param api_type The API flavour the response was requested with
+ * @param response_json The JSON body from the provider
+ * @return Newly allocated content string, or NULL if not found (caller frees)
+ */
+gchar* ai_parse_response_typed(AIApiType api_type, const gchar* response_json);
+
 /**
 * Extract human-readable error message from an API error envelope.
 * Expected format: {"error":{"message":"...","type":"...","code":...}}
--- a/src/command/cmd_ac.c
+++ b/src/command/cmd_ac.c
@@ -47,6 +47,7 @@ static char* _notify_autocomplete(ProfWin* window, const char* const input, gboo
 static char* _theme_autocomplete(ProfWin* window, const char* const input, gboolean previous);
 static char* _spellcheck_autocomplete(ProfWin* window, const char* const input, gboolean previous);
 static char* _autoaway_autocomplete(ProfWin* window, const char* const input, gboolean previous);
+static char* _autoping_autocomplete(ProfWin* window, const char* const input, gboolean previous);
 static char* _autoconnect_autocomplete(ProfWin* window, const char* const input, gboolean previous);
 static char* _account_autocomplete(ProfWin* window, const char* const input, gboolean previous);
 static char* _who_autocomplete(ProfWin* window, const char* const input, gboolean previous);
@@ -263,6 +264,7 @@ static Autocomplete avatar_ac;
 static Autocomplete ai_subcommands_ac;
 static Autocomplete ai_set_subcommands_ac;
 static Autocomplete ai_set_custom_subcommands_ac;
+static Autocomplete ai_api_types_ac;
 static Autocomplete ai_remove_subcommands_ac;
 static Autocomplete url_ac;
 static Autocomplete executable_ac;
@@ -452,6 +454,7 @@ static Autocomplete* all_acs[] = {
    &ai_subcommands_ac,
    &ai_set_subcommands_ac,
    &ai_set_custom_subcommands_ac,
+    &ai_api_types_ac,
    &ai_remove_subcommands_ac,
    &ai_models_ac
 };
@@ -1056,6 +1059,7 @@ cmd_ac_init(void)

    autocomplete_add(autoping_ac, "set");
    autocomplete_add(autoping_ac, "timeout");
+    autocomplete_add(autoping_ac, "warning");

    autocomplete_add(plugins_ac, "install");
    autocomplete_add(plugins_ac, "update");
@@ -1181,12 +1185,12 @@ 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-model", FALSE);
+    autocomplete_add_unsorted(ai_set_subcommands_ac, "api-type", FALSE);
    autocomplete_add_unsorted(ai_set_subcommands_ac, "custom", FALSE);

-    autocomplete_add_unsorted(ai_set_custom_subcommands_ac, "tools", FALSE);
-    autocomplete_add_unsorted(ai_set_custom_subcommands_ac, "search", FALSE);
-    autocomplete_add_unsorted(ai_set_custom_subcommands_ac, "memory", FALSE);
-    autocomplete_add_unsorted(ai_set_custom_subcommands_ac, "plugins", FALSE);
+    autocomplete_add_unsorted(ai_api_types_ac, "chat-completions", FALSE);
+    autocomplete_add_unsorted(ai_api_types_ac, "responses", FALSE);
+    autocomplete_add_unsorted(ai_api_types_ac, "auto", FALSE);

    autocomplete_add_unsorted(ai_remove_subcommands_ac, "provider", FALSE);

@@ -1407,6 +1411,7 @@ cmd_ac_init(void)
    g_hash_table_insert(ac_funcs, "/alias", _alias_autocomplete);
    g_hash_table_insert(ac_funcs, "/autoaway", _autoaway_autocomplete);
    g_hash_table_insert(ac_funcs, "/autoconnect", _autoconnect_autocomplete);
+    g_hash_table_insert(ac_funcs, "/autoping", _autoping_autocomplete);
    g_hash_table_insert(ac_funcs, "/avatar", _avatar_autocomplete);
    g_hash_table_insert(ac_funcs, "/ban", _ban_autocomplete);
    g_hash_table_insert(ac_funcs, "/blocked", _blocked_autocomplete);
@@ -1934,7 +1939,6 @@ _cmd_ac_complete_params(ProfWin* window, const char* const input, gboolean previ
        { "/prefs", prefs_ac },
        { "/disco", disco_ac },
        { "/room", room_ac },
-        { "/autoping", autoping_ac },
        { "/mainwin", winpos_ac },
        { "/inputwin", winpos_ac },
    };
@@ -4264,6 +4268,20 @@ _executable_autocomplete(ProfWin* window, const char* const input, gboolean prev
    return result;
 }

+static char*
+_autoping_autocomplete(ProfWin* window, const char* const input, gboolean previous)
+{
+    char* result = NULL;
+
+    result = autocomplete_param_with_ac(input, "/autoping", autoping_ac, TRUE, previous);
+    if (result) {
+        return result;
+    }
+
+    result = autocomplete_param_with_func(input, "/autoping warning", prefs_autocomplete_boolean_choice, previous, NULL);
+    return result;
+}
+
 static char*
 _lastactivity_autocomplete(ProfWin* window, const char* const input, gboolean previous)
 {
@@ -4516,17 +4534,67 @@ _force_encryption_autocomplete(ProfWin* window, const char* const input, gboolea
 static char* _ai_provider_and_model_autocomplete(ProfWin* window, const char* const input,
                                                 gboolean previous, const char* cmd);

+static char*
+_ai_api_type_find(const char* const search_str, gboolean previous, void* context)
+{
+    return autocomplete_complete(ai_api_types_ac, search_str, FALSE, previous);
+}
+
+static char*
+_ai_custom_setting_find(const char* const search_str, gboolean previous, void* context)
+{
+    return autocomplete_complete(ai_set_custom_subcommands_ac, search_str, FALSE, previous);
+}
+
+/**
+ * Autocomplete the setting name for /ai set custom <provider> <setting>.
+ * Offers a few common payload parameters merged with the keys already set
+ * on the provider, so existing settings can be retyped or overridden.
+ */
+static char*
+_ai_custom_setting_autocomplete(const char* const input, gboolean previous)
+{
+    if (!g_str_has_prefix(input, "/ai set custom ")) {
+        return NULL;
+    }
+
+    /* Quote-aware parse: args[2] is the provider, args[3] the setting being
+     * typed; skip the rebuild when the caret is not at the setting position */
+    gboolean parse_result = FALSE;
+    auto_gcharv gchar** args = parse_args(input, 1, 5, &parse_result);
+    if (!parse_result) {
+        return NULL;
+    }
+    guint num_args = g_strv_length(args);
+    if (num_args < 3 || num_args > 4 || !ai_get_provider(args[2])) {
+        return NULL;
+    }
+
+    /* Rebuild the completion list: common parameters + the provider's keys */
+    gchar* suggestions[] = { "temperature", "max_tokens", "top_p" };
+    GList* keys = ai_get_provider_setting_keys(args[2]);
+    char** items = g_new0(char*, ARRAY_SIZE(suggestions) + g_list_length(keys) + 1);
+    guint i = 0;
+    for (; i < ARRAY_SIZE(suggestions); i++) {
+        items[i] = suggestions[i];
+    }
+    for (GList* curr = keys; curr; curr = g_list_next(curr)) {
+        items[i++] = curr->data;
+    }
+    autocomplete_update(ai_set_custom_subcommands_ac, items);
+    g_free(items);
+    g_list_free_full(keys, g_free);
+
+    /* /ai(1) set(2) custom(3) <provider>(4) <setting>(5) */
+    return autocomplete_param_no_with_func(input, "/ai set custom", 5, _ai_custom_setting_find, previous, NULL);
+}
+
 static char*
 _ai_autocomplete(ProfWin* window, const char* const input, gboolean previous)
 {
    char* result = NULL;

-    /* Parse once for reuse - /ai <subcommand> [<arg1>] [<arg2>] */
-    gboolean parse_result = FALSE;
-    auto_gcharv gchar** args = parse_args(input, 1, 4, &parse_result);
-    int num_args = g_strv_length(args);
-
-    /* Top-level /ai <subcommand> autocomplete (e.g., /ai s<tab> -> /ai set) */
+    // /ai set provider <name> <url> - autocomplete provider names (for updating)
    result = autocomplete_param_with_func(input, "/ai set provider", ai_providers_find, previous, NULL);
    if (result) {
        return result;
@@ -4544,24 +4612,30 @@ _ai_autocomplete(ProfWin* window, const char* const input, gboolean previous)
        return result;
    }

+    // /ai set api-type <provider> <type> - autocomplete the type value
+    result = autocomplete_param_no_with_func(input, "/ai set api-type", 5, _ai_api_type_find, previous, NULL);
+    if (result) {
+        return result;
+    }
+
+    // /ai set api-type <provider> - autocomplete provider names
+    result = autocomplete_param_with_func(input, "/ai set api-type", ai_providers_find, previous, NULL);
+    if (result) {
+        return result;
+    }
+
    // /ai set custom <provider> <setting> <value> - autocomplete provider names
    result = autocomplete_param_with_func(input, "/ai set custom", ai_providers_find, previous, NULL);
    if (result) {
        return result;
    }

-    // /ai set custom <provider> <setting> - autocomplete settings
-    /* args[0]="set", args[1]="custom", args[2]=provider (if typed), args[3]=setting (if typed) */
-    if (num_args == 3 && g_strcmp0(args[1], "custom") == 0) {
-        /* /ai set custom <provider> - check if provider is valid */
-        if (ai_get_provider(args[2])) {
-            /* Valid provider, try settings autocomplete */
-            result = autocomplete_param_with_ac(input, "/ai set custom ", ai_set_custom_subcommands_ac, TRUE, previous);
-            if (result) {
-                return result;
-            }
-        }
+    // /ai set custom <provider> <setting> - autocomplete setting names
+    result = _ai_custom_setting_autocomplete(input, previous);
+    if (result) {
+        return result;
    }
+
    // /ai set <subcommand> - autocomplete subcommands
    result = autocomplete_param_with_ac(input, "/ai set", ai_set_subcommands_ac, TRUE, previous);
    if (result) {
--- a/src/command/cmd_defs.c
+++ b/src/command/cmd_defs.c
@@ -1964,12 +1964,14 @@ static const struct cmd_t command_defs[] = {
              CMD_TAG_CONNECTION)
      CMD_SYN(
              "/autoping set <seconds>",
-              "/autoping timeout <seconds>")
+              "/autoping timeout <seconds>",
+              "/autoping warning on|off")
      CMD_DESC(
              "Set the interval between sending ping requests to the server to ensure the connection is kept alive.")
      CMD_ARGS(
              { "set <seconds>", "Number of seconds between sending pings, a value of 0 disables autoping." },
-              { "timeout <seconds>", "Seconds to wait for autoping responses, after which the connection is considered broken." })
+              { "timeout <seconds>", "Seconds to wait for autoping responses, after which the connection is considered broken." },
+              { "warning on|off", "Enable or disable autoping availability warning." })
    },

    { CMD_PREAMBLE("/ping",
@@ -2813,6 +2815,7 @@ static const struct cmd_t command_defs[] = {
              "/ai set provider <name> <url>",
              "/ai set token <provider> <token>",
              "/ai set default-model <provider> <model>",
+              "/ai set api-type <provider> chat-completions|responses|auto",
              "/ai set custom <provider> <setting> <value>",
              "/ai remove provider <name>",
              "/ai providers",
@@ -2828,10 +2831,11 @@ static const struct cmd_t command_defs[] = {
              "Chat history is maintained per session and not persisted locally.")
      CMD_ARGS(
              { "", "Display current AI settings and configured providers" },
-              { "set provider <name> <url>", "Add or update a provider with custom API endpoint" },
+              { "set provider <name> <url>", "Add or update a provider with a custom API base URL (endpoint paths are appended automatically)" },
              { "set token <provider> <token>", "Set API token for a provider (e.g., openai, perplexity)" },
              { "set default-model <provider> <model>", "Set default model for a provider" },
-              { "set custom <provider> <setting> <value>", "Set provider-level setting (e.g., tools, search)" },
+              { "set api-type <provider> chat-completions|responses|auto", "Pin the provider API flavour; auto tries responses and falls back to chat completions when the endpoint is missing" },
+              { "set custom <provider> <setting> <value>", "Set provider-level setting (e.g., temperature, max_tokens)" },
              { "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)" },
@@ -2842,9 +2846,10 @@ static const struct cmd_t command_defs[] = {
              "/ai",
              "/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 provider custom https://my-api.com/",
              "/ai set default-model perplexity sonar",
-              "/ai set custom perplexity tools enabled",
+              "/ai set api-type perplexity responses",
+              "/ai set custom perplexity temperature 0.7",
              "/ai remove provider custom",
              "/ai start",
              "/ai start perplexity",
--- a/src/command/cmd_funcs.c
+++ b/src/command/cmd_funcs.c
@@ -6374,6 +6374,8 @@ cmd_autoping(ProfWin* window, const char* const command, gchar** args)
            cons_bad_cmd_usage(command);
        }

+    } else if (g_strcmp0(cmd, "warning") == 0) {
+        _cmd_set_boolean_preference(value, "Autoping availability warning", PREF_AUTOPING_WARNING);
    } else {
        cons_bad_cmd_usage(command);
    }
@@ -10063,8 +10065,14 @@ cmd_vcard_remove(ProfWin* window, const char* const command, gchar** args)
    }

    if (args[1]) {
-        vcard_user_remove_element(atoi(args[1]));
-        cons_show("Removed element at index %d", atoi(args[1]));
+        int index;
+        auto_gchar gchar* err_msg = NULL;
+        if (!strtoi_range(args[1], &index, 0, INT_MAX, &err_msg)) {
+            cons_show_error("%s", err_msg);
+            return TRUE;
+        }
+        vcard_user_remove_element((unsigned int)index);
+        cons_show("Removed element at index %d", index);
        vcardwin_update();
    } else {
        cons_bad_cmd_usage(command);
@@ -10695,6 +10703,19 @@ cmd_vcard_save(ProfWin* window, const char* const command, gchar** args)
    return TRUE;
 }

+/* Show the provider's API flavour: pinned, or auto with the detected one */
+static void
+_cons_show_ai_api_type(AIProvider* provider)
+{
+    AIApiType api_type = g_atomic_int_get(&provider->api_type);
+    AIApiType resolved = g_atomic_int_get(&provider->resolved_api_type);
+    if (api_type != AI_API_TYPE_AUTO) {
+        cons_show("    API type: %s", ai_api_type_to_string(api_type));
+    } else if (resolved != AI_API_TYPE_AUTO) {
+        cons_show("    API type: auto (detected: %s)", ai_api_type_to_string(resolved));
+    }
+}
+
 gboolean
 cmd_ai(ProfWin* window, const char* const command, gchar** args)
 {
@@ -10716,6 +10737,7 @@ cmd_ai(ProfWin* window, const char* const command, gchar** args)
            if (default_model) {
                cons_show("    Default model: %s", default_model);
            }
+            _cons_show_ai_api_type(provider);
            if (provider->models && g_list_length(provider->models) > 0) {
                cons_show("    Cached models: %d", g_list_length(provider->models));
            }
@@ -10773,14 +10795,30 @@ cmd_ai_set(ProfWin* window, const char* const command, gchar** args)
        cons_show("Default model for provider '%s' set to: %s", args[2], args[3]);
        cons_show("");
        return TRUE;
+    } else if (g_strcmp0(args[1], "api-type") == 0) {
+        // /ai set api-type <provider> chat-completions|responses|auto
+        if (g_strv_length(args) < 4) {
+            cons_bad_cmd_usage(command);
+            return TRUE;
+        }
+        if (ai_set_provider_api_type(args[2], args[3])) {
+            cons_show("API type for provider '%s' set to: %s", args[2], args[3]);
+        } else {
+            cons_show_error("Cannot set API type for provider '%s': unknown provider or invalid type (use chat-completions, responses, or auto).", args[2]);
+        }
+        cons_show("");
+        return TRUE;
    } else if (g_strcmp0(args[1], "custom") == 0) {
        // /ai set custom <provider> <setting> <value>
        if (g_strv_length(args) < 5) {
            cons_bad_cmd_usage(command);
            return TRUE;
        }
-        ai_set_provider_setting(args[2], args[3], args[4]);
-        cons_show("Setting '%s' for provider '%s' set to: %s", args[3], args[2], args[4]);
+        if (ai_set_provider_setting(args[2], args[3], args[4])) {
+            cons_show("Setting '%s' for provider '%s' set to: %s", args[3], args[2], args[4]);
+        } else {
+            cons_show_error("Cannot set '%s' for provider '%s': unknown provider or reserved key (model, messages, input, stream).", args[3], args[2]);
+        }
        cons_show("");
        return TRUE;
    }
@@ -11094,6 +11132,7 @@ cmd_ai_providers(ProfWin* window, const char* const command, gchar** args)
        cons_show("  %s", provider->name);
        cons_show("    URL: %s", provider->api_url);
        cons_show("    Key: %s", key ? "configured" : "NOT configured");
+        _cons_show_ai_api_type(provider);
        cons_show("");
    }
    g_list_free(providers);
--- a/src/common.c
+++ b/src/common.c
@@ -294,7 +294,7 @@ str_replace(const char* string, const char* substr,
    wr = newstr;

    while ((tok = strstr(head, substr))) {
-        size_t l = tok - head;
+        size_t l = g_diff_to_gsize(tok, head);
        memcpy(wr, head, l);
        wr += l;
        memcpy(wr, replacement, len_replacement);
@@ -309,6 +309,16 @@ str_replace(const char* string, const char* substr,
    return newstr;
 }

+gsize
+g_diff_to_gsize(const void* end, const void* start)
+{
+    if (end < start) {
+        log_error("g_diff_to_gsize: end < start (%p < %p)", end, start);
+        return 0;
+    }
+    return (gsize)((const char*)end - (const char*)start);
+}
+
 gboolean
 strtoi_range(const char* str, int* saveptr, int min, int max, gchar** err_msg)
 {
@@ -359,9 +369,9 @@ string_matches_one_of(const char* what, const char* is, gboolean is_can_be_null,
        char errmsg[256] = { 0 };
        size_t sz = 0;
        int s = snprintf(errmsg, sizeof(errmsg) - sz, "%s must be one of:", what);
-        if (s < 0 || s + sz >= sizeof(errmsg))
+        if (s < 0 || (size_t)s + sz >= sizeof(errmsg))
            return ret;
-        sz += s;
+        sz += (size_t)s;

        cur = first;
        va_start(ap, first);
@@ -375,12 +385,12 @@ string_matches_one_of(const char* what, const char* is, gboolean is_can_be_null,
                errmsg[sz] = '\0';
                s = snprintf(errmsg + sz, sizeof(errmsg) - sz, " or '%s'.", cur);
            }
-            if (s < 0 || s + sz >= sizeof(errmsg)) {
+            if (s < 0 || (size_t)s + sz >= sizeof(errmsg)) {
                log_debug("Error message too long or some other error occurred (%d).", s);
                s = -1;
                break;
            }
-            sz += s;
+            sz += (size_t)s;
            cur = next;
        }
        va_end(ap);
@@ -431,7 +441,7 @@ str_xml_sanitize(const char* const str)
        return NULL;
    }

-    GString* sanitized = g_string_new_len(NULL, strlen(str));
+    GString* sanitized = g_string_new_len(NULL, (gssize)strlen(str));
    const char* curr = str;

    while (*curr != '\0') {
@@ -690,7 +700,7 @@ get_file_paths_recursive(const char* path, GSList** contents)
 }

 gchar*
-get_random_string(int length)
+get_random_string(size_t length)
 {
    GRand* prng;
    gchar* rand;
@@ -701,7 +711,7 @@ get_random_string(int length)

    prng = g_rand_new();

-    for (int i = 0; i < length; i++) {
+    for (size_t i = 0; i < length; i++) {
        rand[i] = alphabet[g_rand_int_range(prng, 0, endrange)];
    }
    g_rand_free(prng);
@@ -748,17 +758,17 @@ call_external(gchar** argv)
 *
 * This function constructs an argument vector (argv) based on the provided template string, replacing placeholders ("%u" and "%p") with the provided URL and filename, respectively.
 *
- * @param template  The template string with placeholders.
- * @param url       The URL to replace "%u" (or NULL to skip).
- * @param filename  The filename to replace "%p" (or NULL to skip).
- * @return          The constructed argument vector (argv) as a null-terminated array of strings.
+ * @param template_fmt  The template string with placeholders.
+ * @param url           The URL to replace "%u" (or NULL to skip).
+ * @param filename      The filename to replace "%p" (or NULL to skip).
+ * @return              The constructed argument vector (argv) as a null-terminated array of strings.
 *
 * @note Remember to free the returned argument vector using `auto_gcharv` or `g_strfreev()`.
 */
 gchar**
-format_call_external_argv(const char* template, const char* url, const char* filename)
+format_call_external_argv(const char* template_fmt, const char* url, const char* filename)
 {
-    gchar** argv = g_strsplit(template, " ", 0);
+    gchar** argv = g_strsplit(template_fmt, " ", 0);

    guint num_args = 0;
    while (argv[num_args]) {
@@ -767,7 +777,7 @@ format_call_external_argv(const char* template, const char* url, const char* fil
            argv[num_args] = g_strdup(url);
        } else if (0 == g_strcmp0(argv[num_args], "%p") && filename != NULL) {
            g_free(argv[num_args]);
-            argv[num_args] = strdup(filename);
+            argv[num_args] = g_strdup(filename);
        }
        num_args++;
    }
--- a/src/common.h
+++ b/src/common.h
@@ -158,6 +158,7 @@ gboolean create_dir(const char* name);
 gboolean copy_file(const char* const src, const char* const target, const gboolean overwrite_existing);
 char* str_replace(const char* string, const char* substr, const char* replacement);
 gboolean strtoi_range(const char* str, int* saveptr, int min, int max, char** err_msg);
+gsize g_diff_to_gsize(const void* end, const void* start);
 int utf8_display_len(const char* const str);
 gchar* str_xml_sanitize(const char* const str);

@@ -178,10 +179,10 @@ int is_regular_file(const char* path);
 int is_dir(const char* path);
 void get_file_paths_recursive(const char* directory, GSList** contents);

-gchar* get_random_string(int length);
+gchar* get_random_string(size_t length);

 gboolean call_external(gchar** argv);
-gchar** format_call_external_argv(const char* template, const char* url, const char* filename);
+gchar** format_call_external_argv(const char* template_fmt, const char* url, const char* filename);

 gchar* unique_filename_from_url(const char* url, const char* path);
 gchar* get_expanded_path(const char* path);
--- a/src/config/accounts.c
+++ b/src/config/accounts.c
@@ -43,8 +43,8 @@ _sanitize_account_name(const char* const name)
    gchar* sanitized = g_strdup(name);
    gchar* p = sanitized;
    while (*p) {
-        // GKeyFile special characters: [ ] = # \n \r
-        if (*p == '[' || *p == ']' || *p == '=' || *p == '#' || *p == '\n' || *p == '\r') {
+        // GKeyFile group header forbids these characters.
+        if (*p == '[' || *p == ']' || *p == '\n' || *p == '\r') {
            *p = '_';
        }
        p++;
--- a/src/config/preferences.c
+++ b/src/config/preferences.c
@@ -2002,6 +2002,30 @@ prefs_ai_get_default_model(const char* const provider)
    return _ai_get_string(provider, "default_model");
 }

+/* --- API type --- */
+
+gboolean
+prefs_ai_set_api_type(const char* const provider, const char* const api_type)
+{
+    if (!provider || !api_type || !prefs)
+        return FALSE;
+    if (api_type[0] == '\0')
+        return prefs_ai_remove_api_type(provider);
+    return _ai_set_string(provider, "api_type", api_type);
+}
+
+gboolean
+prefs_ai_remove_api_type(const char* const provider)
+{
+    return _ai_remove_string(provider, "api_type");
+}
+
+char*
+prefs_ai_get_api_type(const char* const provider)
+{
+    return _ai_get_string(provider, "api_type");
+}
+
 /* --- Provider URL --- */

 gboolean
@@ -2290,6 +2314,7 @@ _get_group(preference_t pref)
    case PREF_TRAY:
    case PREF_TRAY_READ:
    case PREF_ADV_NOTIFY_DISCO_OR_VERSION:
+    case PREF_AUTOPING_WARNING:
        return PREF_GROUP_NOTIFICATIONS;
    case PREF_DBLOG:
    case PREF_CHLOG:
@@ -2646,6 +2671,8 @@ _get_key(preference_t pref)
        return "enabled";
    case PREF_SPELLCHECK_LANG:
        return "lang";
+    case PREF_AUTOPING_WARNING:
+        return "autoping.warning";
    default:
        return NULL;
    }
@@ -2699,6 +2726,7 @@ _get_default_boolean(preference_t pref)
    case PREF_MOOD:
    case PREF_STROPHE_SM_ENABLED:
    case PREF_STROPHE_SM_RESEND:
+    case PREF_AUTOPING_WARNING:
        return TRUE;
    case PREF_SPELLCHECK_ENABLE:
    case PREF_PGP_PUBKEY_AUTOIMPORT:
--- a/src/config/preferences.h
+++ b/src/config/preferences.h
@@ -169,6 +169,7 @@ typedef enum {
    PREF_FORCE_ENCRYPTION_MODE,
    PREF_SPELLCHECK_ENABLE,
    PREF_SPELLCHECK_LANG,
+    PREF_AUTOPING_WARNING
 } preference_t;

 typedef struct prof_alias_t
@@ -367,6 +368,11 @@ gboolean prefs_ai_set_default_model(const char* const provider, const char* cons
 gboolean prefs_ai_remove_default_model(const char* const provider);
 char* prefs_ai_get_default_model(const char* const provider);

+/* AI API type per provider ("responses" or "chat-completions") */
+gboolean prefs_ai_set_api_type(const char* const provider, const char* const api_type);
+gboolean prefs_ai_remove_api_type(const char* const provider);
+char* prefs_ai_get_api_type(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);
--- a/src/database_export.c
+++ b/src/database_export.c
@@ -282,7 +282,7 @@ _export_one_contact(const char* contact)
        gchar* key = _make_dedup_key(pl->stanza_id, pl->timestamp_str, pl->from_jid, pl->message);
        g_hash_table_add(seen_keys, key);
    }
-    int existing_count = g_slist_length(existing);
+    int existing_count = (int)g_slist_length(existing);

    // 2. Query SQLite for this contact — get ALL messages via direct SQL
    GSList* sqlite_lines = db_sqlite_get_all_chat(contact);
@@ -581,7 +581,7 @@ log_database_import_from_flatfile(const gchar* const contact_jid)
        //    Wrap in a transaction for atomicity and performance
        int contact_imported = 0;
        int contact_skipped = 0;
-        int total_lines = g_slist_length(ff_lines);
+        int total_lines = (int)g_slist_length(ff_lines);

        db_sqlite_begin_transaction();
        gboolean import_ok = TRUE;
--- a/src/database_flatfile.c
+++ b/src/database_flatfile.c
@@ -88,7 +88,7 @@ _ff_cache_line_ids(ff_contact_state_t* state, const char* line)
        return;

    // Split metadata on unescaped '|'
-    auto_gchar gchar* meta_str = g_strndup(bracket + 1, close - bracket - 1);
+    auto_gchar gchar* meta_str = g_strndup(bracket + 1, g_diff_to_gsize(close, bracket + 1));
    char** parts = ff_split_meta(meta_str);

    char* stanza_id = NULL;
@@ -111,9 +111,9 @@ _ff_cache_line_ids(ff_contact_state_t* state, const char* line)
        const char* sender_start = close + 2;
        const char* colonspace = ff_find_unescaped_colonspace(sender_start);
        if (colonspace) {
-            const char* slash = memchr(sender_start, '/', colonspace - sender_start);
+            const char* slash = memchr(sender_start, '/', g_diff_to_gsize(colonspace, sender_start));
            const char* jid_end = slash ? slash : colonspace;
-            from_jid = g_strndup(sender_start, jid_end - sender_start);
+            from_jid = g_strndup(sender_start, g_diff_to_gsize(jid_end, sender_start));
        }
    }

@@ -140,7 +140,7 @@ _ff_maybe_index_line(ff_contact_state_t* state, const char* buf, off_t pos)
    if (!space)
        return;

-    auto_gchar gchar* ts_str = g_strndup(buf, space - buf);
+    auto_gchar gchar* ts_str = g_strndup(buf, g_diff_to_gsize(space, buf));
    GDateTime* dt = g_date_time_new_from_iso8601(ts_str, NULL);
    if (!dt) {
        log_warning("flatfile: unparsable timestamp in %s at offset %ld: %s",
@@ -771,7 +771,7 @@ _flatfile_get_previous_chat(const gchar* const contact_barejid, const gchar* sta

    // For "last N messages": back up from read_to using index
    if (!from_start) {
-        int margin_entries = (MESSAGES_TO_RETRIEVE * 3) / FF_INDEX_STEP + 2;
+        size_t margin_entries = (MESSAGES_TO_RETRIEVE * 3) / FF_INDEX_STEP + 2;

        // Find index entry closest to (but before) read_to
        size_t entry_idx = 0;
@@ -781,7 +781,7 @@ _flatfile_get_previous_chat(const gchar* const contact_barejid, const gchar* sta
            entry_idx = i;
        }

-        size_t start_entry = entry_idx > (size_t)margin_entries
+        size_t start_entry = entry_idx > margin_entries
                                 ? entry_idx - margin_entries
                                 : 0;
        off_t backed = state->entries[start_entry].byte_offset;
--- a/src/database_flatfile_parser.c
+++ b/src/database_flatfile_parser.c
@@ -553,7 +553,7 @@ ff_split_meta(const char* meta)
            continue;
        }
        if (*p == '|' || *p == '\0') {
-            g_ptr_array_add(arr, g_strndup(start, p - start));
+            g_ptr_array_add(arr, g_strndup(start, g_diff_to_gsize(p, start)));
            if (*p == '\0')
                break;
            start = p + 1;
@@ -710,7 +710,7 @@ ff_parse_line(const char* line)

    if (bracket_start && first_space && first_space < bracket_start) {
        // Standard format with metadata: {timestamp} [{meta}] {sender}: {msg}
-        result->timestamp_str = g_strndup(work, first_space - work);
+        result->timestamp_str = g_strndup(work, g_diff_to_gsize(first_space, work));

        // Parse metadata section [...]
        const char* bracket_end = ff_find_unescaped_char(bracket_start + 1, ']');
@@ -721,7 +721,7 @@ ff_parse_line(const char* line)
            return NULL;
        }

-        auto_gchar gchar* meta_content = g_strndup(bracket_start + 1, bracket_end - bracket_start - 1);
+        auto_gchar gchar* meta_content = g_strndup(bracket_start + 1, g_diff_to_gsize(bracket_end, bracket_start + 1));
        char** parts = ff_split_meta(meta_content);
        if (parts) {
            _ff_parse_meta_parts(parts, result);
@@ -736,12 +736,12 @@ ff_parse_line(const char* line)
        // Find first *unescaped* ': ' which separates sender from message.
        const char* colon = ff_find_unescaped_colonspace(after_meta);
        if (colon) {
-            auto_gchar gchar* raw_sender = g_strndup(after_meta, colon - after_meta);
+            auto_gchar gchar* raw_sender = g_strndup(after_meta, g_diff_to_gsize(colon, after_meta));

            // Split sender into jid/resource, then unescape resource
            char* slash = strchr(raw_sender, '/');
            if (slash) {
-                result->from_jid = g_strndup(raw_sender, slash - raw_sender);
+                result->from_jid = g_strndup(raw_sender, g_diff_to_gsize(slash, raw_sender));
                result->from_resource = ff_unescape_sender_resource(slash + 1);
            } else {
                result->from_jid = g_strdup(raw_sender);
@@ -755,7 +755,7 @@ ff_parse_line(const char* line)
        }
    } else if (first_space) {
        // Legacy/simple format without metadata: {timestamp} - {sender}: {msg}
-        result->timestamp_str = g_strndup(work, first_space - work);
+        result->timestamp_str = g_strndup(work, g_diff_to_gsize(first_space, work));
        result->type = g_strdup("chat");
        result->enc = g_strdup("none");

@@ -767,10 +767,10 @@ ff_parse_line(const char* line)

        char* colon = strstr(rest, ": ");
        if (colon) {
-            char* sender = g_strndup(rest, colon - rest);
+            char* sender = g_strndup(rest, g_diff_to_gsize(colon, rest));
            char* slash = strchr(sender, '/');
            if (slash) {
-                result->from_jid = g_strndup(sender, slash - sender);
+                result->from_jid = g_strndup(sender, g_diff_to_gsize(slash, sender));
                result->from_resource = g_strdup(slash + 1);
            } else {
                result->from_jid = g_strdup(sender);
--- a/src/event/common.h
+++ b/src/event/common.h
@@ -10,6 +10,8 @@
 #ifndef EVENT_COMMON_H
 #define EVENT_COMMON_H

+#include "glib.h"
+
 void ev_disconnect_cleanup(void);
 void ev_inc_connection_counter(void);
 void ev_reset_connection_counter(void);
--- a/src/gitversion.h.in
+++ b/src/gitversion.h.in
@@ -1,6 +0,0 @@
-#ifndef PROF_GIT_BRANCH
-#define PROF_GIT_BRANCH @PROF_GIT_BRANCH@
-#endif
-#ifndef PROF_GIT_REVISION
-#define PROF_GIT_REVISION @PROF_GIT_REVISION@
-#endif
--- a/src/omemo/omemo.c
+++ b/src/omemo/omemo.c
@@ -260,7 +260,12 @@ omemo_on_connect(ProfAccount* account)
            return;
    }

-    _omemo_finalize_identity_load(account);
+    if (!_omemo_finalize_identity_load(account)) {
+        omemo_ctx.loaded = FALSE;
+        log_error("[OMEMO] failed to load OMEMO state from disk for %s", account->jid);
+        cons_show_error("OMEMO: could not load encryption state from disk; OMEMO will be unavailable this session.");
+        return;
+    }

    wins_omemo_trust_changed(NULL);
 }
@@ -1278,8 +1283,12 @@ omemo_is_trusted_identity(const char* const jid, const char* const fingerprint)
        .device_id = GPOINTER_TO_UINT(device_id),
    };

-    size_t fingerprint_len;
+    size_t fingerprint_len = 0;
    unsigned char* fingerprint_raw = _omemo_fingerprint_decode(fingerprint, &fingerprint_len);
+    if (!fingerprint_raw) {
+        log_error("[OMEMO] omemo_is_trusted_identity: failed to decode fingerprint for %s", jid);
+        return FALSE;
+    }
    unsigned char djb_type[] = { '\x05' };
    signal_buffer* buffer = signal_buffer_create(djb_type, 1);
    buffer = signal_buffer_append(buffer, fingerprint_raw, fingerprint_len);
@@ -1463,6 +1472,10 @@ _omemo_fingerprint(ec_public_key* identity, gboolean formatted)
 static unsigned char*
 _omemo_fingerprint_decode(const char* const fingerprint, size_t* len)
 {
+    if (!fingerprint) {
+        *len = 0;
+        return NULL;
+    }
    unsigned char* output = malloc(strlen(fingerprint) / 2 + 1);
    if (!output) {
        *len = 0;
@@ -1529,6 +1542,11 @@ omemo_trust(const char* const jid, const char* const fingerprint_formatted)
    };

    unsigned char* fingerprint_raw = _omemo_fingerprint_decode(fingerprint_formatted, &len);
+    if (!fingerprint_raw) {
+        log_error("[OMEMO] omemo_trust: failed to decode fingerprint for %s", jid);
+        cons_show_error("Failed to trust device: could not decode fingerprint.");
+        return;
+    }
    unsigned char djb_type[] = { '\x05' };
    signal_buffer* buffer = signal_buffer_create(djb_type, 1);
    buffer = signal_buffer_append(buffer, fingerprint_raw, len);
@@ -1546,8 +1564,10 @@ omemo_untrust(const char* const jid, const char* const fingerprint_formatted)
 {
    size_t len;
    unsigned char* identity = _omemo_fingerprint_decode(fingerprint_formatted, &len);
-    if (!identity)
+    if (!identity) {
+        log_error("[OMEMO] omemo_untrust: failed to decode fingerprint for %s", jid);
        return;
+    }

    GHashTableIter iter;
    gpointer key, value;
--- a/src/otr/otr.c
+++ b/src/otr/otr.c
@@ -278,7 +278,8 @@ otr_on_message_recv(const char* const barejid, const char* const resource, const
                if (strstr(message, OTRL_MESSAGE_TAG_V2) && strstr(message, OTRL_MESSAGE_TAG_V1)) {
                    tag_length = 32;
                }
-                memmove(whitespace_base, whitespace_base + tag_length, tag_length);
+                // Move the rest of the message (with NUL) over the tag.
+                memmove(whitespace_base, whitespace_base + tag_length, strlen(whitespace_base + tag_length) + 1);
                char* otr_query_message = otr_start_query();
                cons_show("OTR Whitespace pattern detected. Attempting to start OTR session…");
                free(message_send_chat_otr(barejid, otr_query_message, FALSE, NULL));
--- a/src/pgp/gpg.c
+++ b/src/pgp/gpg.c
@@ -519,13 +519,15 @@ p_gpg_sign(const gchar* const str, const gchar* const fp)
 }

 gchar*
-p_gpg_encrypt(const gchar* const barejid, const gchar* const message, const gchar* const fp)
+p_gpg_encrypt(const gchar* const barejid, const gchar* const message, const gchar* const fp, gchar** err)
 {
    ProfPGPPubKeyId* pubkeyid = g_hash_table_lookup(pubkeys, barejid);
    if (!pubkeyid) {
+        *err = g_strdup("No PGP key found for recipient");
        return NULL;
    }
    if (!pubkeyid->id) {
+        *err = g_strdup("No key ID found for recipient");
        return NULL;
    }

@@ -538,6 +540,7 @@ p_gpg_encrypt(const gchar* const barejid, const gchar* const message, const gcha
    gpgme_ctx_t ctx;
    gpgme_error_t error = gpgme_new(&ctx);
    if (error) {
+        *err = g_strdup_printf("Failed to create GPGME context: %s %s", gpgme_strsource(error), gpgme_strerror(error));
        log_error("GPG: Failed to create gpgme context. %s %s", gpgme_strsource(error), gpgme_strerror(error));
        return NULL;
    }
@@ -545,6 +548,7 @@ p_gpg_encrypt(const gchar* const barejid, const gchar* const message, const gcha
    gpgme_key_t receiver_key;
    error = gpgme_get_key(ctx, pubkeyid->id, &receiver_key, 0);
    if (error || receiver_key == NULL) {
+        *err = g_strdup_printf("Failed to get receiver key '%s': %s %s", pubkeyid->id, gpgme_strsource(error), gpgme_strerror(error));
        log_error("GPG: Failed to get receiver_key. %s %s", gpgme_strsource(error), gpgme_strerror(error));
        gpgme_release(ctx);
        return NULL;
@@ -554,8 +558,10 @@ p_gpg_encrypt(const gchar* const barejid, const gchar* const message, const gcha
    gpgme_key_t sender_key = NULL;
    error = gpgme_get_key(ctx, fp, &sender_key, 0);
    if (error || sender_key == NULL) {
+        *err = g_strdup_printf("Failed to get sender key '%s': %s %s", fp, gpgme_strsource(error), gpgme_strerror(error));
        log_error("GPG: Failed to get sender_key. %s %s", gpgme_strsource(error), gpgme_strerror(error));
        gpgme_release(ctx);
+        gpgme_key_unref(receiver_key);
        return NULL;
    }
    keys[1] = sender_key;
@@ -574,7 +580,8 @@ p_gpg_encrypt(const gchar* const barejid, const gchar* const message, const gcha
    gpgme_key_unref(sender_key);

    if (error) {
-        log_error("GPG: Failed to encrypt message. %s %s", gpgme_strsource(error), gpgme_strerror(error));
+        *err = g_strdup_printf("Encryption failed: (%s) %s", gpgme_strsource(error), gpgme_strerror(error));
+        log_error("GPG: Failed to encrypt message. (%s) %s", gpgme_strsource(error), gpgme_strerror(error));
        return NULL;
    }

--- a/src/pgp/gpg.h
+++ b/src/pgp/gpg.h
@@ -10,6 +10,8 @@
 #ifndef PGP_GPG_H
 #define PGP_GPG_H

+#include "glib.h"
+
 typedef struct pgp_key_t
 {
    gchar* id;
@@ -40,7 +42,7 @@ gboolean p_gpg_available(const gchar* const barejid);
 const gchar* p_gpg_libver(void);
 gchar* p_gpg_sign(const gchar* const str, const gchar* const fp);
 void p_gpg_verify(const gchar* const barejid, const gchar* const sign);
-gchar* p_gpg_encrypt(const gchar* const barejid, const gchar* const message, const gchar* const fp);
+gchar* p_gpg_encrypt(const gchar* const barejid, const gchar* const message, const gchar* const fp, gchar** err);
 gchar* p_gpg_decrypt(const gchar* const cipher);
 void p_gpg_free_decrypted(gchar* decrypted);
 gchar* p_gpg_autocomplete_key(const gchar* const search_str, gboolean previous, void* context);
--- a/src/profanity.c
+++ b/src/profanity.c
@@ -138,7 +138,7 @@ prof_run(gchar* log_level, gchar* account_name, gchar* config_file, gchar* log_f
                     * so we can be sure there's runtime left after executing
                     * the last command.
                     */
-                    min_runtime += waittime;
+                    min_runtime += (unsigned int)waittime;
                } else {
                    log_error("%s", err_msg);
                    g_free(err_msg);
--- a/src/tools/bookmark_ignore.h
+++ b/src/tools/bookmark_ignore.h
@@ -10,8 +10,10 @@
 #ifndef BOOKMARK_IGNORE_H
 #define BOOKMARK_IGNORE_H

+#include "xmpp/xmpp.h"
+
 void bookmark_ignore_on_connect(const char* const barejid);
-void bookmark_ignore_on_disconnect(void);
+void bookmark_ignore_on_disconnect();
 gboolean bookmark_ignored(Bookmark* bookmark);
 gchar** bookmark_ignore_list(gsize* len);
 void bookmark_ignore_add(const char* const barejid);
--- a/src/ui/console.c
+++ b/src/ui/console.c
@@ -1703,6 +1703,11 @@ cons_notify_setting(void)
    else
        cons_show("Subscription requests (/notify sub) : OFF");

+    if (prefs_get_boolean(PREF_AUTOPING_WARNING))
+        cons_show("Autoping warning (/autoping warning): ON");
+    else
+        cons_show("Autoping warning (/autoping warning): OFF");
+
    gint remind_period = prefs_get_notify_remind();
    if (remind_period == 0) {
        cons_show("Reminder period (/notify remind)    : OFF");
@@ -2003,21 +2008,26 @@ cons_autoping_setting(void)
 {
    gint autoping_interval = prefs_get_autoping();
    if (autoping_interval == 0) {
-        cons_show("Autoping interval (/autoping)   : OFF");
+        cons_show("Autoping interval (/autoping)       : OFF");
    } else if (autoping_interval == 1) {
-        cons_show("Autoping interval (/autoping)   : 1 second");
+        cons_show("Autoping interval (/autoping)       : 1 second");
    } else {
-        cons_show("Autoping interval (/autoping)   : %d seconds", autoping_interval);
+        cons_show("Autoping interval (/autoping)       : %d seconds", autoping_interval);
    }

    gint autoping_timeout = prefs_get_autoping_timeout();
    if (autoping_timeout == 0) {
-        cons_show("Autoping timeout (/autoping)    : OFF");
+        cons_show("Autoping timeout (/autoping)        : OFF");
    } else if (autoping_timeout == 1) {
-        cons_show("Autoping timeout (/autoping)    : 1 second");
+        cons_show("Autoping timeout (/autoping)        : 1 second");
    } else {
-        cons_show("Autoping timeout (/autoping)    : %d seconds", autoping_timeout);
+        cons_show("Autoping timeout (/autoping)        : %d seconds", autoping_timeout);
    }
+
+    if (prefs_get_boolean(PREF_AUTOPING_WARNING))
+        cons_show("Autoping warning (/autoping warning): ON");
+    else
+        cons_show("Autoping warning (/autoping warning): OFF");
 }

 void
--- a/src/ui/titlebar.h
+++ b/src/ui/titlebar.h
@@ -10,6 +10,8 @@
 #ifndef UI_TITLEBAR_H
 #define UI_TITLEBAR_H

+#include "glib.h"
+
 void create_title_bar(void);
 void free_title_bar(void);
 void title_bar_update_virtual(void);
--- a/src/ui/window.c
+++ b/src/ui/window.c
@@ -43,7 +43,7 @@
 #include "ai/ai_client.h"

 static const int PAD_MIN_HEIGHT = 100;
-static const int PAD_THRESHOLD = 3000;
+static const int PAD_DEAD_SPACE_LIMIT = 2000; // reclaim once the pad holds this much dead space (cursor past live buffer); size-independent, so it never fires while scrolling
 static gboolean _in_redraw = FALSE;

 static void
@@ -56,9 +56,10 @@ _win_ensure_pad_capacity(ProfWin* window, WINDOW* win, int lines_needed)
    int cur_height = getmaxy(win);
    int cur_width = getmaxx(win);
    if (lines_needed >= cur_height - 1) {
-        // If we are getting too large, trigger a redraw to clean up old lines
-        // but only if we are not already in a redraw process.
-        if (window && cur_height >= PAD_THRESHOLD && !_in_redraw) {
+        // redraw to reclaim dead pad space (cursor far past live buffer, e.g. a long
+        // append-only session); dead space never accrues while scrolling, only here
+        int dead = window ? getcury(win) - window->layout->buffer->lines : 0;
+        if (window && dead > PAD_DEAD_SPACE_LIMIT && !_in_redraw) {
            win_redraw(window);
        } else {
            // resize to required lines + some buffer for next messages
@@ -67,6 +68,20 @@ _win_ensure_pad_capacity(ProfWin* window, WINDOW* win, int lines_needed)
        }
    }
 }
+
+// upper-bound estimate of rows a message body occupies (hard newlines + soft-wrap), to reserve pad space before printing so a tall message isn't clipped (a clipped height desyncs the scroll offset)
+static int
+_win_estimated_lines(WINDOW* win, const char* const message, int indent, int pad_indent)
+{
+    int usable = MAX(1, getmaxx(win) - (indent + pad_indent));
+    int newlines = 0;
+    for (const char* p = message; *p; p++) {
+        if (*p == '\n') {
+            newlines++;
+        }
+    }
+    return newlines + utf8_display_len(message) / usable + 2;
+}
 static const char* LOADING_MESSAGE = "Loading older messages…";
 static const char* CONS_WIN_TITLE = "CProof. Type /help for help information.";
 static const char* XML_WIN_TITLE = "XML Console";
@@ -2001,7 +2016,7 @@ _win_print_internal(ProfWin* window, const char* show_char, int pad_indent, GDat
        }
    }

-    _win_ensure_pad_capacity(window, window->layout->win, getcury(window->layout->win));
+    _win_ensure_pad_capacity(window, window->layout->win, getcury(window->layout->win) + _win_estimated_lines(window->layout->win, message + offset, indent, pad_indent));

    if (prefs_get_boolean(PREF_WRAP)) {
        _win_print_wrapped(window->layout->win, message + offset, indent, pad_indent);
@@ -2172,9 +2187,10 @@ win_redraw(ProfWin* window)
    unsigned int size = buffer_size(window->layout->buffer);
    _in_redraw = TRUE;

-    // shrink pad back to minimum size and erase it
+    // size the pad to fit the whole buffer (plus headroom) and erase it
    int cols = getmaxx(window->layout->win);
-    wresize(window->layout->win, PAD_MIN_HEIGHT, cols);
+    int needed = window->layout->buffer->lines + 100;
+    wresize(window->layout->win, MAX(needed, PAD_MIN_HEIGHT), cols);
    werase(window->layout->win);

    for (unsigned int i = 0; i < size; i++) {
--- a/src/xmpp/blocking.h
+++ b/src/xmpp/blocking.h
@@ -10,6 +10,8 @@
 #ifndef XMPP_BLOCKING_H
 #define XMPP_BLOCKING_H

+#include <strophe.h>
+
 void blocking_request(void);
 int blocked_set_handler(xmpp_stanza_t* stanza);
 int reporting_set_handler(xmpp_stanza_t* stanza);
--- a/src/xmpp/iq.c
+++ b/src/xmpp/iq.c
@@ -99,6 +99,7 @@ static void _disco_items_result_handler(xmpp_stanza_t* const stanza);
 static void _last_activity_get_handler(xmpp_stanza_t* const stanza);
 static void _version_get_handler(xmpp_stanza_t* const stanza);
 static void _ping_get_handler(xmpp_stanza_t* const stanza);
+static void _disco_autoping_warning_message(GHashTable* features);

 static int _version_result_id_handler(xmpp_stanza_t* const stanza, void* const userdata);
 static int _disco_info_response_id_handler(xmpp_stanza_t* const stanza, void* const userdata);
@@ -2429,6 +2430,12 @@ _disco_info_response_id_handler_onconnect(xmpp_stanza_t* const stanza, void* con
            }
            child = xmpp_stanza_get_next(child);
        }
+
+        // Prevent repetitions by avoiding checks of disco items (from connection_set_disco_items)
+        const char* domain = connection_get_domain();
+        if (from && domain && g_ascii_strcasecmp(from, domain) == 0) {
+            _disco_autoping_warning_message(features);
+        }
    }

    connection_features_received(from);
@@ -2436,6 +2443,21 @@ _disco_info_response_id_handler_onconnect(xmpp_stanza_t* const stanza, void* con
    return 0;
 }

+static void
+_disco_autoping_warning_message(GHashTable* features)
+{
+    gboolean server_supports_ping = g_hash_table_contains(features, "urn:xmpp:ping");
+    gboolean user_prefers_warning = prefs_get_boolean(PREF_AUTOPING_WARNING);
+    gboolean is_autoping_enabled = prefs_get_autoping() != 0;
+
+    if (!is_autoping_enabled && server_supports_ping && user_prefers_warning) {
+        cons_show("This server supports XEP-0199: XMPP Ping (better keepalive detection),\n"
+                  "but autoping feature is currently disabled in settings.\n"
+                  "Consider enabling it (e.g., `/autoping set 30`) for improved connection stability.\n"
+                  "Use `/autoping warning off` to disable this message.");
+    }
+}
+
 static int
 _http_upload_response_id_handler(xmpp_stanza_t* const stanza, void* const userdata)
 {
--- a/src/xmpp/iq.h
+++ b/src/xmpp/iq.h
@@ -10,6 +10,8 @@
 #ifndef XMPP_IQ_H
 #define XMPP_IQ_H

+#include <strophe.h>
+
 typedef int (*ProfIqCallback)(xmpp_stanza_t* const stanza, void* const userdata);
 typedef void (*ProfIqFreeCallback)(void* userdata);

--- a/src/xmpp/jid.c
+++ b/src/xmpp/jid.c
@@ -117,7 +117,7 @@ jid_is_valid(const gchar* const str)

    // Localpart validation
    if (at) {
-        size_t local_len = at - str;
+        size_t local_len = g_diff_to_gsize(at, str);
        if (local_len == 0 || local_len > JID_MAX_PART_LEN) {
            return FALSE;
        }
@@ -135,7 +135,7 @@ jid_is_valid(const gchar* const str)

    // Resourcepart validation if present
    if (slash) {
-        domain_len = slash - domain_start;
+        domain_len = g_diff_to_gsize(slash, domain_start);
        size_t resource_len = strlen(slash + 1);
        if (resource_len > JID_MAX_PART_LEN) {
            return FALSE;
--- a/src/xmpp/message.c
+++ b/src/xmpp/message.c
@@ -65,6 +65,7 @@ static void _handle_pubsub(xmpp_stanza_t* const stanza, xmpp_stanza_t* const eve
 static gboolean _handle_form(xmpp_stanza_t* const stanza);
 static gboolean _handle_jingle_message(xmpp_stanza_t* const stanza);
 static gboolean _should_ignore_based_on_silence(xmpp_stanza_t* const stanza);
+static gboolean _stanza_id_by_trusted(const char* by);
 #ifdef HAVE_OMEMO
 static void _receive_omemo(xmpp_stanza_t* const stanza, ProfMessage* message);
 #endif
@@ -466,12 +467,15 @@ message_send_chat_pgp(const char* const barejid, const char* const msg, gboolean
    auto_char char* jid = chat_session_get_jid(barejid);
    char* id = connection_create_stanza_id();

+    ProfWin* current = wins_get_current();
+
    xmpp_stanza_t* message = NULL;
 #ifdef HAVE_LIBGPGME
    ProfAccount* account = accounts_get_account(session_get_account_name());
    if (account->pgp_keyid) {
        auto_jid Jid* jidp = jid_create(jid);
-        auto_gchar gchar* encrypted = p_gpg_encrypt(jidp->barejid, msg, account->pgp_keyid);
+        auto_gchar gchar* err = NULL;
+        auto_gchar gchar* encrypted = p_gpg_encrypt(jidp->barejid, msg, account->pgp_keyid, &err);
        if (encrypted) {
            message = xmpp_message_new(ctx, STANZA_TYPE_CHAT, jid, id);
            xmpp_message_set_body(message, "This message is encrypted (XEP-0027).");
@@ -485,18 +489,31 @@ message_send_chat_pgp(const char* const barejid, const char* const msg, gboolean
            xmpp_stanza_add_child(message, x);
            xmpp_stanza_release(x);
        } else {
-            message = xmpp_message_new(ctx, STANZA_TYPE_CHAT, jid, id);
-            xmpp_message_set_body(message, msg);
+            if (current) {
+                win_println(current, THEME_ERROR, "-", "Unable to encrypt message for %s: %s.", jid, err);
+            }
+            log_error("Message not encrypted for %s: %s.", jid, err);
+            account_free(account);
+            free(id);
+            return NULL;
        }
    } else {
-        message = xmpp_message_new(ctx, STANZA_TYPE_CHAT, jid, id);
-        xmpp_message_set_body(message, msg);
+        if (current) {
+            win_println(current, THEME_ERROR, "-", "No PGP key configured for this account.");
+        }
+        log_error("No PGP key configured, message not sent.");
+        account_free(account);
+        free(id);
+        return NULL;
    }
    account_free(account);
 #else
-    // ?
-    message = xmpp_message_new(ctx, STANZA_TYPE_CHAT, jid, id);
-    xmpp_message_set_body(message, msg);
+    if (current) {
+        win_println(current, THEME_ERROR, "-", "LibGPGME not available, message not sent.");
+    }
+    log_error("LibGPGME not available, message not sent.");
+    free(id);
+    return NULL;
 #endif

    if (state) {
@@ -545,7 +562,10 @@ message_send_chat_ox(const char* const barejid, const char* const msg, gboolean
    xmpp_stanza_to_text(signcrypt, &c, &s);
    char* signcrypt_e = p_ox_gpg_signcrypt(account->jid, barejid, c);
    if (signcrypt_e == NULL) {
-        cons_show("Unable to send OX message. Check log file and profanity-ox-setup man page for details.");
+        ProfWin* current = wins_get_current();
+        if (current) {
+            win_println(current, THEME_ERROR, "-", "Unable to send OX message. Check log file and profanity-ox-setup man page for details.");
+        }
        log_error("Message not signcrypted.");
        return NULL;
    }
@@ -1088,7 +1108,7 @@ _handle_groupchat(xmpp_stanza_t* const stanza)
    xmpp_stanza_t* stanzaidst = xmpp_stanza_get_child_by_name_and_ns(stanza, STANZA_NAME_STANZA_ID, STANZA_NS_STABLE_ID);
    if (stanzaidst) {
        const char* by = xmpp_stanza_get_attribute(stanzaidst, "by");
-        if (by && (g_strcmp0(by, from_jid->barejid) == 0)) {
+        if (by && g_strcmp0(by, from_jid->barejid) == 0 && _stanza_id_by_trusted(by)) {
            stanzaid = (char*)xmpp_stanza_get_attribute(stanzaidst, STANZA_ATTR_ID);
            if (stanzaid) {
                message->stanzaid = strdup(stanzaid);
@@ -1397,7 +1417,7 @@ _handle_chat(xmpp_stanza_t* const stanza, gboolean is_mam, gboolean is_carbon, c
        xmpp_stanza_t* stanzaidst = xmpp_stanza_get_child_by_name_and_ns(stanza, STANZA_NAME_STANZA_ID, STANZA_NS_STABLE_ID);
        if (stanzaidst) {
            const char* by = xmpp_stanza_get_attribute(stanzaidst, "by");
-            if (by && equals_our_barejid(by)) {
+            if (by && equals_our_barejid(by) && _stanza_id_by_trusted(by)) {
                stanzaid = (char*)xmpp_stanza_get_attribute(stanzaidst, STANZA_ATTR_ID);
                if (stanzaid) {
                    message->stanzaid = strdup(stanzaid);
@@ -1735,3 +1755,22 @@ _should_ignore_based_on_silence(xmpp_stanza_t* const stanza)
    }
    return FALSE;
 }
+
+// XEP-0359 §6 disco-gate; falls back to domain since that's what disco is run against.
+static gboolean
+_stanza_id_by_trusted(const char* by)
+{
+    if (!by) {
+        return FALSE;
+    }
+    GHashTable* features = connection_get_features(by);
+    if (features && g_hash_table_contains(features, STANZA_NS_STABLE_ID)) {
+        return TRUE;
+    }
+    const char* at = strchr(by, '@');
+    if (!at) {
+        return FALSE;
+    }
+    features = connection_get_features(at + 1);
+    return features && g_hash_table_contains(features, STANZA_NS_STABLE_ID);
+}
--- a/src/xmpp/muc.c
+++ b/src/xmpp/muc.c
@@ -707,7 +707,7 @@ muc_autocomplete(ProfWin* window, const char* const input, gboolean previous)
    } else {
        search_str = last_space + 1;
        if (!chat_room->autocomplete_prefix) {
-            chat_room->autocomplete_prefix = g_strndup(input, search_str - input);
+            chat_room->autocomplete_prefix = g_strndup(input, g_diff_to_gsize(search_str, input));
        }
    }

--- a/src/xmpp/ox.h
+++ b/src/xmpp/ox.h
@@ -7,6 +7,8 @@
 * SPDX-License-Identifier: GPL-3.0-or-later WITH OpenSSL-exception
 */

+#include "glib.h"
+
 /*!
 * \page OX OX Implementation
 *
--- a/src/xmpp/presence.c
+++ b/src/xmpp/presence.c
@@ -621,15 +621,20 @@ _available_handler(xmpp_stanza_t* const stanza)
    }

    if (g_strcmp0(xmpp_presence->jid->barejid, my_jid->barejid) == 0) {
-        connection_add_available_resource(resource);
+        // Copy what we read before connection_add_available_resource() takes ownership.
        Resource* resource_for_roster = resource_copy(resource);
+        auto_gchar gchar* resource_name = g_strdup(resource->name);
+        auto_gchar gchar* resource_status = resource->status ? g_strdup(resource->status) : NULL;
+        int resource_priority = resource->priority;
+        resource_presence_t resource_presence = resource->presence;
+        connection_add_available_resource(resource);
        sv_ev_contact_online(xmpp_presence->jid->barejid, resource_for_roster, xmpp_presence->last_activity, pgpsig);
        const char* account_name = session_get_account_name();
        int max_sessions = accounts_get_max_sessions(account_name);
        if (max_sessions > 0) {
            auto_gchar gchar* cur_resource = accounts_get_resource(account_name);
            int res_count = connection_count_available_resources();
-            if (res_count > max_sessions && g_strcmp0(cur_resource, resource->name)) {
+            if (res_count > max_sessions && g_strcmp0(cur_resource, resource_name)) {
                ProfWin* console = wins_get_console();
                ProfWin* current_window = wins_get_current();
                auto_gchar gchar* message = g_strdup_printf("Max sessions alarm! (%d/%d devices in use)", res_count, max_sessions);
@@ -639,14 +644,14 @@ _available_handler(xmpp_stanza_t* const stanza)
                }
                notify(message, 10000, "Security alert");

-                const char* resource_presence = string_from_resource_presence(resource->presence);
-                win_print(console, THEME_DEFAULT, "|", "New device info: \n    %s (%d), %s", resource->name, resource->priority, resource_presence);
+                const char* resource_presence_str = string_from_resource_presence(resource_presence);
+                win_print(console, THEME_DEFAULT, "|", "New device info: \n    %s (%d), %s", resource_name, resource_priority, resource_presence_str);

-                if (resource->status) {
-                    win_append(console, THEME_DEFAULT, ", \"%s\"", resource->status);
+                if (resource_status) {
+                    win_append(console, THEME_DEFAULT, ", \"%s\"", resource_status);
                }
                win_appendln(console, THEME_DEFAULT, "");
-                auto_jid Jid* jidp = jid_create_from_bare_and_resource(my_jid->barejid, resource->name);
+                auto_jid Jid* jidp = jid_create_from_bare_and_resource(my_jid->barejid, resource_name);
                EntityCapabilities* caps = caps_lookup(jidp->fulljid);

                if (caps) {
--- a/src/xmpp/roster.h
+++ b/src/xmpp/roster.h
@@ -10,6 +10,9 @@
 #ifndef XMPP_ROSTER_H
 #define XMPP_ROSTER_H

+#include "glib.h"
+#include <strophe.h>
+
 void roster_request(void);
 void roster_set_handler(xmpp_stanza_t* const stanza);
 void roster_result_handler(xmpp_stanza_t* const stanza);
--- a/src/xmpp/vcard_funcs.h
+++ b/src/xmpp/vcard_funcs.h
@@ -12,6 +12,7 @@

 #include "ui/win_types.h"
 #include "xmpp/vcard.h"
+#include <strophe.h>

 vCard* vcard_new();
 void vcard_free(vCard* vcard);
--- a/tests/functionaltests/functionaltests.c
+++ b/tests/functionaltests/functionaltests.c
@@ -150,6 +150,14 @@ main(int argc, char* argv[])
        PROF_FUNC_TEST(autoping_sends_ping_after_interval),
        PROF_FUNC_TEST(autoping_server_not_supporting_ping),

+        /* Autoping availability warning - negative cases wait ~3s */
+        PROF_FUNC_TEST(autoping_warning_shown_when_disabled),
+        PROF_FUNC_TEST(autoping_warning_not_shown_when_server_unsupported),
+        PROF_FUNC_TEST(autoping_warning_not_shown_when_autoping_enabled),
+        PROF_FUNC_TEST(autoping_warning_not_shown_when_user_disabled),
+        PROF_FUNC_TEST(autoping_warning_not_shown_for_user_jid),
+        PROF_FUNC_TEST(autoping_warning_not_shown_for_subdomain_service),
+
        /* Service Discovery - XEP-0030 */
        PROF_FUNC_TEST(disco_info_shows_identity),
        PROF_FUNC_TEST(disco_info_shows_features),
@@ -253,6 +261,10 @@ main(int argc, char* argv[])
        PROF_FUNC_TEST(message_receive_console),
        PROF_FUNC_TEST(message_receive_chatwin),

+        /* XEP-0359 disco gate for stanza-id trust */
+        PROF_FUNC_TEST(stanza_id_dedup_fires_when_server_announces_sid0),
+        PROF_FUNC_TEST(stanza_id_not_trusted_when_server_does_not_announce_sid0),
+
 #ifdef HAVE_SQLITE
        /* MUC (groupchat) database — export/import of type="muc" messages */
        PROF_FUNC_TEST(muc_export_sqlite_to_flatfile),
--- a/tests/functionaltests/proftest.c
+++ b/tests/functionaltests/proftest.c
@@ -119,10 +119,9 @@ _create_dir(const char* name)
 gboolean
 _mkdir_recursive(const char* dir)
 {
-    int i;
    gboolean result = TRUE;

-    for (i = 1; i <= strlen(dir); i++) {
+    for (size_t i = 1; i <= strlen(dir); i++) {
        if (dir[i] == '/' || dir[i] == '\0') {
            gchar* next_dir = g_strndup(dir, i);
            result = _create_dir(next_dir);
--- a/tests/functionaltests/test_ai.c
+++ b/tests/functionaltests/test_ai.c
@@ -55,11 +55,11 @@ ai_no_args_shows_help(void** state)
 void
 ai_providers_lists_defaults(void** state)
 {
-    /* `/ai providers` (no "list") shows the built-in list with URLs. */
+    /* `/ai providers` (no "list") shows the configured list with URLs. */
    prof_input("/ai providers");

    prof_timeout(5);
-    assert_true(prof_output_exact("Available AI providers:"));
+    assert_true(prof_output_exact("Configured providers:"));
    /* At least one URL line is rendered — exact name agnostic. */
    assert_true(prof_output_regex("https?://"));
    prof_timeout_reset();
--- a/tests/functionaltests/test_autoping.c
+++ b/tests/functionaltests/test_autoping.c
@@ -112,3 +112,144 @@ autoping_server_not_supporting_ping(void** state)
    // Should show error about ping not being supported
    assert_true(prof_output_regex("Server ping not supported"));
 }
+
+/*
+ * Autoping availability warning.
+ *
+ * The warning fires from the on-connect disco handler, so the three inputs
+ * (server ping support, autoping interval, warning preference) must all be
+ * set before prof_connect().
+ */
+
+/* Stable substring of the warning text emitted by iq.c. */
+#define AUTOPING_WARNING_MATCH "This server supports XEP-0199"
+
+static void
+_stub_server_disco(gboolean with_ping)
+{
+    if (with_ping) {
+        stbbr_for_query("http://jabber.org/protocol/disco#info",
+            "<iq to='stabber@localhost/profanity' type='result' from='localhost'>"
+                "<query xmlns='http://jabber.org/protocol/disco#info'>"
+                    "<identity category='server' type='im' name='Stabber'/>"
+                    "<feature var='urn:xmpp:ping'/>"
+                "</query>"
+            "</iq>"
+        );
+    } else {
+        stbbr_for_query("http://jabber.org/protocol/disco#info",
+            "<iq to='stabber@localhost/profanity' type='result' from='localhost'>"
+                "<query xmlns='http://jabber.org/protocol/disco#info'>"
+                    "<identity category='server' type='im' name='Stabber'/>"
+                "</query>"
+            "</iq>"
+        );
+    }
+}
+
+void
+autoping_warning_shown_when_disabled(void** state)
+{
+    // All conditions met: server supports ping, autoping off, warning on (default).
+    _stub_server_disco(TRUE);
+
+    prof_input("/autoping set 0");
+    assert_true(prof_output_exact("Autoping disabled."));
+
+    prof_connect();
+
+    assert_true(prof_output_regex(AUTOPING_WARNING_MATCH));
+}
+
+void
+autoping_warning_not_shown_when_server_unsupported(void** state)
+{
+    // Server does not advertise urn:xmpp:ping -> no warning even with autoping off.
+    _stub_server_disco(FALSE);
+
+    prof_input("/autoping set 0");
+    assert_true(prof_output_exact("Autoping disabled."));
+
+    prof_connect();
+
+    prof_timeout(NEGATIVE_ASSERT_TIMEOUT);
+    assert_false(prof_output_regex(AUTOPING_WARNING_MATCH));
+}
+
+void
+autoping_warning_not_shown_when_autoping_enabled(void** state)
+{
+    // Warning is suppressed while autoping is enabled.
+    _stub_server_disco(TRUE);
+
+    prof_input("/autoping set 30");
+    assert_true(prof_output_exact("Autoping interval set to 30 seconds."));
+
+    prof_connect();
+
+    prof_timeout(NEGATIVE_ASSERT_TIMEOUT);
+    assert_false(prof_output_regex(AUTOPING_WARNING_MATCH));
+}
+
+void
+autoping_warning_not_shown_when_user_disabled(void** state)
+{
+    // User opted out -> no warning.
+    _stub_server_disco(TRUE);
+
+    prof_input("/autoping set 0");
+    assert_true(prof_output_exact("Autoping disabled."));
+
+    prof_input("/autoping warning off");
+    assert_true(prof_output_exact("Autoping availability warning disabled."));
+
+    prof_connect();
+
+    prof_timeout(NEGATIVE_ASSERT_TIMEOUT);
+    assert_false(prof_output_regex(AUTOPING_WARNING_MATCH));
+}
+
+void
+autoping_warning_not_shown_for_user_jid(void** state)
+{
+    // disco#info from a user JID (with '@') should not trigger the warning,
+    // only server responses (no '@') should.
+    stbbr_for_query("http://jabber.org/protocol/disco#info",
+        "<iq to='stabber@localhost/profanity' type='result' from='buddy1@localhost'>"
+            "<query xmlns='http://jabber.org/protocol/disco#info'>"
+                "<identity category='person' type='chat' name='Buddy1'/>"
+                "<feature var='urn:xmpp:ping'/>"
+            "</query>"
+        "</iq>"
+    );
+
+    prof_input("/autoping set 0");
+    assert_true(prof_output_exact("Autoping disabled."));
+
+    prof_connect();
+
+    prof_timeout(NEGATIVE_ASSERT_TIMEOUT);
+    assert_false(prof_output_regex(AUTOPING_WARNING_MATCH));
+}
+
+void
+autoping_warning_not_shown_for_subdomain_service(void** state)
+{
+    // disco#info from a subdomain service should not trigger the warning, only the server's own domain should
+    stbbr_for_query("http://jabber.org/protocol/disco#info",
+        "<iq to='stabber@localhost/profanity' type='result' from='conf.localhost'>"
+            "<query xmlns='http://jabber.org/protocol/disco#info'>"
+                "<identity category='conference' type='text' name='Conference Service'/>"
+                "<feature var='urn:xmpp:ping'/>"
+            "</query>"
+        "</iq>"
+    );
+
+    prof_input("/autoping set 0");
+    assert_true(prof_output_exact("Autoping disabled."));
+
+    prof_connect();
+
+    prof_timeout(NEGATIVE_ASSERT_TIMEOUT);
+    assert_false(prof_output_regex(AUTOPING_WARNING_MATCH));
+}
--- a/tests/functionaltests/test_autoping.h
+++ b/tests/functionaltests/test_autoping.h
@@ -4,3 +4,9 @@ void autoping_timeout_set(void** state);
 void autoping_timeout_zero_disables(void** state);
 void autoping_sends_ping_after_interval(void** state);
 void autoping_server_not_supporting_ping(void** state);
+void autoping_warning_shown_when_disabled(void** state);
+void autoping_warning_not_shown_when_server_unsupported(void** state);
+void autoping_warning_not_shown_when_autoping_enabled(void** state);
+void autoping_warning_not_shown_when_user_disabled(void** state);
+void autoping_warning_not_shown_for_user_jid(void** state);
+void autoping_warning_not_shown_for_subdomain_service(void** state);
--- a/tests/functionaltests/test_message.c
+++ b/tests/functionaltests/test_message.c
@@ -56,3 +56,70 @@ message_receive_chatwin(void **state)

    assert_true(prof_output_regex("someuser@chatserv.org/laptop: .+How are you?"));
 }
+
+// XEP-0359 disco gate: server announces urn:xmpp:sid:0 -> stanza-id trusted -> replay flagged as duplicate.
+void
+stanza_id_dedup_fires_when_server_announces_sid0(void **state)
+{
+    stbbr_for_query("http://jabber.org/protocol/disco#info",
+        "<iq type='result' to='stabber@localhost/profanity' from='localhost'>"
+            "<query xmlns='http://jabber.org/protocol/disco#info'>"
+                "<identity category='server' type='im' name='TestServer'/>"
+                "<feature var='urn:xmpp:sid:0'/>"
+            "</query>"
+        "</iq>"
+    );
+
+    prof_connect();
+
+    stbbr_send(
+        "<message id='m-trust-1' to='stabber@localhost' from='someuser@chatserv.org/laptop' type='chat'>"
+            "<body>first</body>"
+            "<stanza-id xmlns='urn:xmpp:sid:0' by='stabber@localhost' id='archive-id-42'/>"
+        "</message>"
+    );
+    assert_true(prof_output_exact("<< chat message: someuser@chatserv.org/laptop (win 2)"));
+
+    stbbr_send(
+        "<message id='m-trust-2' to='stabber@localhost' from='someuser@chatserv.org/laptop' type='chat'>"
+            "<body>replay</body>"
+            "<stanza-id xmlns='urn:xmpp:sid:0' by='stabber@localhost' id='archive-id-42'/>"
+        "</message>"
+    );
+    assert_true(prof_output_exact("Got a message with duplicate (server-generated) stanza-id from someuser@chatserv.org/laptop."));
+}
+
+// XEP-0359 disco gate: server does NOT announce urn:xmpp:sid:0 -> stanza-id untrusted -> no replay error.
+void
+stanza_id_not_trusted_when_server_does_not_announce_sid0(void **state)
+{
+    stbbr_for_query("http://jabber.org/protocol/disco#info",
+        "<iq type='result' to='stabber@localhost/profanity' from='localhost'>"
+            "<query xmlns='http://jabber.org/protocol/disco#info'>"
+                "<identity category='server' type='im' name='TestServer'/>"
+                "<feature var='urn:xmpp:ping'/>"
+            "</query>"
+        "</iq>"
+    );
+
+    prof_connect();
+
+    stbbr_send(
+        "<message id='m-untrust-1' to='stabber@localhost' from='someuser@chatserv.org/laptop' type='chat'>"
+            "<body>first</body>"
+            "<stanza-id xmlns='urn:xmpp:sid:0' by='stabber@localhost' id='archive-id-77'/>"
+        "</message>"
+    );
+    assert_true(prof_output_exact("<< chat message: someuser@chatserv.org/laptop (win 2)"));
+
+    stbbr_send(
+        "<message id='m-untrust-2' to='stabber@localhost' from='someuser@chatserv.org/laptop' type='chat'>"
+            "<body>replay</body>"
+            "<stanza-id xmlns='urn:xmpp:sid:0' by='stabber@localhost' id='archive-id-77'/>"
+        "</message>"
+    );
+
+    prof_timeout(2);
+    assert_false(prof_output_exact("Got a message with duplicate (server-generated) stanza-id"));
+    prof_timeout_reset();
+}
--- a/tests/functionaltests/test_message.h
+++ b/tests/functionaltests/test_message.h
@@ -1,3 +1,5 @@
 void message_send(void **state);
 void message_receive_console(void **state);
 void message_receive_chatwin(void **state);
+void stanza_id_dedup_fires_when_server_announces_sid0(void **state);
+void stanza_id_not_trusted_when_server_does_not_announce_sid0(void **state);
--- a/tests/unittests/test_ai_client.c
+++ b/tests/unittests/test_ai_client.c
@@ -62,12 +62,10 @@ test_ai_add_provider(void** state)
    assert_string_equal("custom", provider->name);
    assert_string_equal("https://custom.api.com/v1", provider->api_url);

-    /* Update existing provider (returns ref; caller owns it) */
+    /* Update existing provider (borrowed pointer, same as the create path) */
    AIProvider* updated = ai_add_provider("custom", "https://new.api.com/v1");
    assert_non_null(updated);
    assert_string_equal("https://new.api.com/v1", updated->api_url);
-
-    ai_provider_unref(updated);
 }

 void
@@ -329,11 +327,10 @@ test_ai_add_provider_update_existing(void** state)
    assert_non_null(provider);
    assert_string_equal("https://first.api.com/v1", provider->api_url);

-    /* Update the same provider (returns ref) */
+    /* Update the same provider (borrowed pointer) */
    provider = ai_add_provider("custom", "https://second.api.com/v1");
    assert_non_null(provider);
    assert_string_equal("https://second.api.com/v1", provider->api_url);
-    ai_provider_unref(provider);
 }

 void
@@ -614,6 +611,112 @@ test_ai_set_provider_setting(void** state)
    assert_null(ai_get_provider_setting("p_set_settings", "nonexistent_setting"));
 }

+void
+test_ai_set_provider_setting_reserved_key(void** state)
+{
+    ai_add_provider("p_reserved_keys", "https://example.test/rk/");
+
+    /* Reserved payload keys are rejected (would duplicate fixed fields) */
+    assert_false(ai_set_provider_setting("p_reserved_keys", "model", "x"));
+    assert_false(ai_set_provider_setting("p_reserved_keys", "messages", "[]"));
+    assert_false(ai_set_provider_setting("p_reserved_keys", "input", "[]"));
+    assert_false(ai_set_provider_setting("p_reserved_keys", "stream", "true"));
+    assert_null(ai_get_provider_setting("p_reserved_keys", "model"));
+
+    /* "store" is a legitimate chat-completions parameter and overrides the
+     * responses-flavour "store":false default, so it stays settable */
+    assert_true(ai_set_provider_setting("p_reserved_keys", "store", "true"));
+    auto_gchar gchar* store = ai_get_provider_setting("p_reserved_keys", "store");
+    assert_non_null(store);
+    assert_string_equal("true", store);
+
+    /* Ordinary keys still work */
+    assert_true(ai_set_provider_setting("p_reserved_keys", "temperature", "0.7"));
+    auto_gchar gchar* temp = ai_get_provider_setting("p_reserved_keys", "temperature");
+    assert_non_null(temp);
+    assert_string_equal("0.7", temp);
+}
+
+void
+test_ai_get_provider_setting_keys(void** state)
+{
+    ai_add_provider("p_setting_keys", "https://example.test/skeys/");
+
+    /* No settings yet, unknown provider, NULL — all yield NULL */
+    assert_null(ai_get_provider_setting_keys("p_setting_keys"));
+    assert_null(ai_get_provider_setting_keys("nonexistent"));
+    assert_null(ai_get_provider_setting_keys(NULL));
+
+    ai_set_provider_setting("p_setting_keys", "temperature", "0.7");
+    ai_set_provider_setting("p_setting_keys", "reasoning_effort", "high");
+
+    /* Both keys listed (order is hash-defined, assert membership) */
+    GList* keys = ai_get_provider_setting_keys("p_setting_keys");
+    assert_int_equal(2, g_list_length(keys));
+    assert_non_null(g_list_find_custom(keys, "temperature", (GCompareFunc)g_strcmp0));
+    assert_non_null(g_list_find_custom(keys, "reasoning_effort", (GCompareFunc)g_strcmp0));
+    g_list_free_full(keys, g_free);
+
+    /* Removing a setting removes its key */
+    ai_set_provider_setting("p_setting_keys", "temperature", NULL);
+    keys = ai_get_provider_setting_keys("p_setting_keys");
+    assert_int_equal(1, g_list_length(keys));
+    assert_string_equal("reasoning_effort", keys->data);
+    g_list_free_full(keys, g_free);
+}
+
+void
+test_ai_set_provider_api_type(void** state)
+{
+    ai_add_provider("p_api_type", "https://example.test/at/");
+
+    /* Default is auto */
+    assert_int_equal(AI_API_TYPE_AUTO, ai_get_provider_api_type("p_api_type"));
+
+    /* Pin each flavour explicitly */
+    assert_true(ai_set_provider_api_type("p_api_type", "chat-completions"));
+    assert_int_equal(AI_API_TYPE_CHAT_COMPLETIONS, ai_get_provider_api_type("p_api_type"));
+
+    assert_true(ai_set_provider_api_type("p_api_type", "responses"));
+    assert_int_equal(AI_API_TYPE_RESPONSES, ai_get_provider_api_type("p_api_type"));
+
+    /* auto resets to detection */
+    assert_true(ai_set_provider_api_type("p_api_type", "auto"));
+    assert_int_equal(AI_API_TYPE_AUTO, ai_get_provider_api_type("p_api_type"));
+
+    /* Invalid values and unknown providers are rejected */
+    assert_false(ai_set_provider_api_type("p_api_type", "v2"));
+    assert_false(ai_set_provider_api_type("p_api_type", NULL));
+    assert_false(ai_set_provider_api_type("nonexistent", "responses"));
+    assert_false(ai_set_provider_api_type(NULL, "responses"));
+
+    /* Unknown provider reads as auto */
+    assert_int_equal(AI_API_TYPE_AUTO, ai_get_provider_api_type("nonexistent"));
+    assert_int_equal(AI_API_TYPE_AUTO, ai_get_provider_api_type(NULL));
+}
+
+void
+test_ai_api_type_string_round_trip(void** state)
+{
+    AIApiType type = AI_API_TYPE_AUTO;
+
+    assert_true(ai_api_type_from_string("responses", &type));
+    assert_int_equal(AI_API_TYPE_RESPONSES, type);
+    assert_string_equal("responses", ai_api_type_to_string(type));
+
+    assert_true(ai_api_type_from_string("chat-completions", &type));
+    assert_int_equal(AI_API_TYPE_CHAT_COMPLETIONS, type);
+    assert_string_equal("chat-completions", ai_api_type_to_string(type));
+
+    assert_true(ai_api_type_from_string("auto", &type));
+    assert_int_equal(AI_API_TYPE_AUTO, type);
+    assert_string_equal("auto", ai_api_type_to_string(type));
+
+    assert_false(ai_api_type_from_string("completions", &type));
+    assert_false(ai_api_type_from_string("", &type));
+    assert_false(ai_api_type_from_string(NULL, &type));
+}
+
 void
 test_ai_get_provider_setting(void** state)
 {
@@ -919,8 +1022,10 @@ test_ai_parse_response_openai_content(void** state)
 }

 void
-test_ai_parse_response_perplexity_text(void** state)
+test_ai_parse_response_responses_output_text(void** state)
 {
+    /* Responses API: "content" is an array of typed parts; the inner "text"
+     * of the output_text part is the assistant message. */
    const gchar* json = "{\"output\":[{\"content\":[{\"text\":\"Search result\",\"type\":\"output_text\"}]}]}";
    auto_gchar gchar* out = ai_parse_response(json);
    assert_non_null(out);
@@ -928,13 +1033,180 @@ test_ai_parse_response_perplexity_text(void** state)
 }

 void
-test_ai_parse_response_text_preferred_over_content(void** state)
+test_ai_parse_response_responses_full_envelope(void** state)
 {
-    /* When both formats are present, "text" wins (Perplexity path tried first). */
+    /* Realistic responses body: a reasoning item precedes the message item;
+     * the parser must still land on the message's output_text. */
+    const gchar* json = "{\"id\":\"resp_1\",\"object\":\"response\",\"status\":\"completed\","
+                        "\"output\":["
+                        "{\"id\":\"rs_1\",\"type\":\"reasoning\",\"summary\":[]},"
+                        "{\"id\":\"msg_1\",\"type\":\"message\",\"status\":\"completed\",\"role\":\"assistant\","
+                        "\"content\":[{\"type\":\"output_text\",\"annotations\":[],\"text\":\"Hello!\"}]}"
+                        "]}";
+    auto_gchar gchar* out = ai_parse_response(json);
+    assert_non_null(out);
+    assert_string_equal("Hello!", out);
+}
+
+void
+test_ai_parse_response_choices_win_over_output(void** state)
+{
+    /* A chat-completions envelope is authoritative even if the content
+     * happens to mention "output". */
+    const gchar* json = "{\"choices\":[{\"message\":{\"content\":\"chat result\"}}],\"output\":[{\"content\":[{\"text\":\"wrong\"}]}]}";
+    auto_gchar gchar* out = ai_parse_response(json);
+    assert_non_null(out);
+    assert_string_equal("chat result", out);
+}
+
+void
+test_ai_parse_response_responses_reasoning_summary_skipped(void** state)
+{
+    /* A reasoning item with a non-empty summary precedes the message item;
+     * the summary's "text" must not be mistaken for the assistant reply. */
+    const gchar* json = "{\"output\":["
+                        "{\"id\":\"rs_1\",\"type\":\"reasoning\",\"summary\":[{\"type\":\"summary_text\",\"text\":\"User asks X\"}]},"
+                        "{\"id\":\"msg_1\",\"type\":\"message\",\"status\":\"completed\",\"role\":\"assistant\","
+                        "\"content\":[{\"type\":\"output_text\",\"annotations\":[],\"text\":\"Actual answer\"}]}"
+                        "]}";
+    auto_gchar gchar* out = ai_parse_response(json);
+    assert_non_null(out);
+    assert_string_equal("Actual answer", out);
+}
+
+void
+test_ai_parse_response_responses_reasoning_only_returns_null(void** state)
+{
+    /* An incomplete/truncated body with only a reasoning item (no message
+     * "content" array at all) must yield a parse failure, not leak the
+     * reasoning summary's "text" as the assistant reply. */
+    const gchar* json = "{\"status\":\"incomplete\",\"output\":["
+                        "{\"type\":\"reasoning\",\"summary\":[{\"type\":\"summary_text\",\"text\":\"secret reasoning\"}]}"
+                        "]}";
+    gchar* out = ai_parse_response(json);
+    assert_null(out);
+}
+
+void
+test_ai_parse_response_responses_reasoning_after_message_skipped(void** state)
+{
+    /* A reasoning item ordered after the message, with the part's "text"
+     * preceding "type":"output_text": the forward scan must stay inside the
+     * part's object and the backscan must find the real answer. */
+    const gchar* json = "{\"output\":["
+                        "{\"type\":\"message\",\"content\":[{\"text\":\"answer\",\"type\":\"output_text\"}]},"
+                        "{\"type\":\"reasoning\",\"summary\":[{\"type\":\"summary_text\",\"text\":\"secret\"}]}"
+                        "]}";
+    auto_gchar gchar* out = ai_parse_response(json);
+    assert_non_null(out);
+    assert_string_equal("answer", out);
+}
+
+void
+test_ai_parse_response_responses_empty_content_not_leaked(void** state)
+{
+    /* An empty content array followed by a reasoning item must yield a parse
+     * failure; the scan must not escape the array and return the summary. */
+    const gchar* json = "{\"output\":["
+                        "{\"type\":\"message\",\"content\":[]},"
+                        "{\"type\":\"reasoning\",\"summary\":[{\"type\":\"summary_text\",\"text\":\"secret\"}]}"
+                        "]}";
+    gchar* out = ai_parse_response(json);
+    assert_null(out);
+}
+
+void
+test_ai_parse_response_responses_text_value_before_later_item(void** state)
+{
+    /* A reply that is exactly "text" plus a reasoning item after the message:
+     * the backscan's own extraction must also stay inside the part's object. */
+    const gchar* json = "{\"output\":["
+                        "{\"type\":\"message\",\"content\":[{\"text\":\"text\",\"type\":\"output_text\"}]},"
+                        "{\"type\":\"reasoning\",\"summary\":[{\"type\":\"summary_text\",\"text\":\"secret\"}]}"
+                        "]}";
+    auto_gchar gchar* out = ai_parse_response(json);
+    assert_non_null(out);
+    assert_string_equal("text", out);
+}
+
+void
+test_ai_parse_response_choices_in_string_value(void** state)
+{
+    /* "choices" occurring as a string value must not hijack a valid
+     * responses envelope. */
+    const gchar* json = "{\"kind\":\"choices\",\"output\":[{\"content\":[{\"type\":\"output_text\",\"text\":\"hi\"}]}]}";
+    auto_gchar gchar* out = ai_parse_response(json);
+    assert_non_null(out);
+    assert_string_equal("hi", out);
+}
+
+void
+test_ai_parse_response_content_before_choices(void** state)
+{
+    /* Nonstandard body: a top-level content string precedes an empty
+     * choices array; the bare-content fallback must still find it. */
+    const gchar* json = "{\"content\":\"hi\",\"choices\":[]}";
+    auto_gchar gchar* out = ai_parse_response(json);
+    assert_non_null(out);
+    assert_string_equal("hi", out);
+}
+
+void
+test_ai_parse_response_content_preferred_over_text(void** state)
+{
+    /* Chat-completions "content" is extracted; a stray "text" field is ignored. */
    const gchar* json = "{\"text\":\"from text field\",\"content\":\"from content field\"}";
    auto_gchar gchar* out = ai_parse_response(json);
    assert_non_null(out);
-    assert_string_equal("from text field", out);
+    assert_string_equal("from content field", out);
+}
+
+void
+test_ai_parse_response_responses_brace_in_text(void** state)
+{
+    /* Responses part with "text" before "type":"output_text" and a '{' inside
+     * the answer: the nearest preceding "text" key must be extracted, not a
+     * brace inside the string value. */
+    const gchar* json = "{\"output\":[{\"content\":[{\"text\":\"use { here\",\"type\":\"output_text\"}]}]}";
+    auto_gchar gchar* out = ai_parse_response(json);
+    assert_non_null(out);
+    assert_string_equal("use { here", out);
+}
+
+void
+test_ai_parse_response_choices_logprobs_before_content(void** state)
+{
+    /* A non-string "content" (logprobs array) ordered before message.content
+     * must not defeat extraction; anchoring on "message" finds the reply. */
+    const gchar* json = "{\"choices\":[{\"logprobs\":{\"content\":[{\"token\":\"hi\"}]},"
+                        "\"message\":{\"role\":\"assistant\",\"content\":\"real answer\"}}]}";
+    auto_gchar gchar* out = ai_parse_response(json);
+    assert_non_null(out);
+    assert_string_equal("real answer", out);
+}
+
+void
+test_ai_parse_response_reasoning_not_leaked_without_text(void** state)
+{
+    /* An output_text part with no "text" at all (truncated body) must yield a
+     * parse failure, not leak the preceding reasoning summary's text. */
+    const gchar* json = "{\"output\":["
+                        "{\"type\":\"reasoning\",\"summary\":[{\"type\":\"summary_text\",\"text\":\"secret\"}]},"
+                        "{\"type\":\"message\",\"content\":[{\"type\":\"output_text\",\"annotations\":[]}]}"
+                        "]}";
+    gchar* out = ai_parse_response(json);
+    assert_null(out);
+}
+
+void
+test_ai_parse_response_responses_text_value_text(void** state)
+{
+    /* A reply that is exactly the string "text" must not confuse the
+     * backscan (the value's own quoted bytes match the key needle). */
+    const gchar* json = "{\"output\":[{\"content\":[{\"text\":\"text\",\"type\":\"output_text\"}]}]}";
+    auto_gchar gchar* out = ai_parse_response(json);
+    assert_non_null(out);
+    assert_string_equal("text", out);
 }

 void
@@ -1474,6 +1746,26 @@ test_ai_prefs_round_trip_remove_key(void** state)
    assert_null(after);
 }

+void
+test_ai_prefs_round_trip_api_type(void** state)
+{
+    ai_add_provider("p_persist_api_type", "https://example.test/pat/");
+    assert_true(ai_set_provider_api_type("p_persist_api_type", "chat-completions"));
+
+    ai_client_shutdown();
+    ai_client_init();
+
+    assert_int_equal(AI_API_TYPE_CHAT_COMPLETIONS, ai_get_provider_api_type("p_persist_api_type"));
+
+    /* Setting auto removes the persisted value */
+    assert_true(ai_set_provider_api_type("p_persist_api_type", "auto"));
+
+    ai_client_shutdown();
+    ai_client_init();
+
+    assert_int_equal(AI_API_TYPE_AUTO, ai_get_provider_api_type("p_persist_api_type"));
+}
+
 void
 test_ai_prefs_multiple_providers_persist(void** state)
 {
--- a/tests/unittests/test_ai_client.h
+++ b/tests/unittests/test_ai_client.h
@@ -43,6 +43,10 @@ void test_ai_providers_find_case_insensitive(void** state);
 void test_ai_set_provider_default_model(void** state);
 void test_ai_get_provider_default_model(void** state);
 void test_ai_set_provider_setting(void** state);
+void test_ai_set_provider_setting_reserved_key(void** state);
+void test_ai_get_provider_setting_keys(void** state);
+void test_ai_set_provider_api_type(void** state);
+void test_ai_api_type_string_round_trip(void** state);
 void test_ai_get_provider_setting(void** state);
 /* Model caching tests */
 void test_ai_models_are_fresh_initial(void** state);
@@ -64,8 +68,21 @@ int ai_client_teardown_with_prefs(void** state);

 /* Chat response parser tests (ai_parse_response) */
 void test_ai_parse_response_openai_content(void** state);
-void test_ai_parse_response_perplexity_text(void** state);
-void test_ai_parse_response_text_preferred_over_content(void** state);
+void test_ai_parse_response_responses_output_text(void** state);
+void test_ai_parse_response_responses_full_envelope(void** state);
+void test_ai_parse_response_responses_reasoning_summary_skipped(void** state);
+void test_ai_parse_response_choices_win_over_output(void** state);
+void test_ai_parse_response_choices_in_string_value(void** state);
+void test_ai_parse_response_content_before_choices(void** state);
+void test_ai_parse_response_content_preferred_over_text(void** state);
+void test_ai_parse_response_responses_brace_in_text(void** state);
+void test_ai_parse_response_choices_logprobs_before_content(void** state);
+void test_ai_parse_response_reasoning_not_leaked_without_text(void** state);
+void test_ai_parse_response_responses_reasoning_only_returns_null(void** state);
+void test_ai_parse_response_responses_reasoning_after_message_skipped(void** state);
+void test_ai_parse_response_responses_empty_content_not_leaked(void** state);
+void test_ai_parse_response_responses_text_value_before_later_item(void** state);
+void test_ai_parse_response_responses_text_value_text(void** state);
 void test_ai_parse_response_escaped_quote(void** state);
 void test_ai_parse_response_newline_escape(void** state);
 void test_ai_parse_response_empty_content(void** state);
@@ -128,6 +145,7 @@ void test_ai_parse_models_multiple_models(void** state);
 /* Prefs round-trip tests */
 void test_ai_prefs_round_trip_api_key(void** state);
 void test_ai_prefs_round_trip_remove_key(void** state);
+void test_ai_prefs_round_trip_api_type(void** state);
 void test_ai_prefs_multiple_providers_persist(void** state);

 /* Autocomplete deeper coverage */
--- a/tests/unittests/unittests.c
+++ b/tests/unittests/unittests.c
@@ -752,6 +752,10 @@ main(int argc, char* argv[])
        cmocka_unit_test_setup_teardown(test_ai_set_provider_default_model, ai_client_setup, ai_client_teardown),
        cmocka_unit_test_setup_teardown(test_ai_get_provider_default_model, ai_client_setup, ai_client_teardown),
        cmocka_unit_test_setup_teardown(test_ai_set_provider_setting, ai_client_setup, ai_client_teardown),
+        cmocka_unit_test_setup_teardown(test_ai_set_provider_setting_reserved_key, ai_client_setup, ai_client_teardown),
+        cmocka_unit_test_setup_teardown(test_ai_get_provider_setting_keys, ai_client_setup, ai_client_teardown),
+        cmocka_unit_test_setup_teardown(test_ai_set_provider_api_type, ai_client_setup, ai_client_teardown),
+        cmocka_unit_test(test_ai_api_type_string_round_trip),
        cmocka_unit_test_setup_teardown(test_ai_get_provider_setting, ai_client_setup, ai_client_teardown),
        /* Model caching tests */
        cmocka_unit_test_setup_teardown(test_ai_models_are_fresh_initial, ai_client_setup, ai_client_teardown),
@@ -774,8 +778,21 @@ main(int argc, char* argv[])
        cmocka_unit_test(test_ai_json_escape_backslash_quote),
        /* Chat response parser */
        cmocka_unit_test(test_ai_parse_response_openai_content),
-        cmocka_unit_test(test_ai_parse_response_perplexity_text),
-        cmocka_unit_test(test_ai_parse_response_text_preferred_over_content),
+        cmocka_unit_test(test_ai_parse_response_responses_output_text),
+        cmocka_unit_test(test_ai_parse_response_responses_full_envelope),
+        cmocka_unit_test(test_ai_parse_response_responses_reasoning_summary_skipped),
+        cmocka_unit_test(test_ai_parse_response_choices_win_over_output),
+        cmocka_unit_test(test_ai_parse_response_choices_in_string_value),
+        cmocka_unit_test(test_ai_parse_response_content_before_choices),
+        cmocka_unit_test(test_ai_parse_response_content_preferred_over_text),
+        cmocka_unit_test(test_ai_parse_response_responses_brace_in_text),
+        cmocka_unit_test(test_ai_parse_response_choices_logprobs_before_content),
+        cmocka_unit_test(test_ai_parse_response_reasoning_not_leaked_without_text),
+        cmocka_unit_test(test_ai_parse_response_responses_reasoning_only_returns_null),
+        cmocka_unit_test(test_ai_parse_response_responses_reasoning_after_message_skipped),
+        cmocka_unit_test(test_ai_parse_response_responses_empty_content_not_leaked),
+        cmocka_unit_test(test_ai_parse_response_responses_text_value_before_later_item),
+        cmocka_unit_test(test_ai_parse_response_responses_text_value_text),
        cmocka_unit_test(test_ai_parse_response_escaped_quote),
        cmocka_unit_test(test_ai_parse_response_newline_escape),
        cmocka_unit_test(test_ai_parse_response_empty_content),
@@ -830,6 +847,7 @@ main(int argc, char* argv[])
        /* Prefs round-trip (uses prefs+ai setup) */
        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_round_trip_api_type, 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),