diff --git a/misc/api.func b/misc/api.func
index 17f9cd9e8..693dfef7a 100644
--- a/misc/api.func
+++ b/misc/api.func
@@ -28,21 +28,96 @@
 # ==============================================================================
 
 # ==============================================================================
-# SECTION 1: DEPENDENCY LOADING
+# SECTION 1: ERROR CODE DESCRIPTIONS
 # ==============================================================================
 
-# Load error_handler.func for explain_exit_code() function
-# This provides centralized error code descriptions (exit codes 1-255, shell, package managers, databases, custom Proxmox codes)
-if [[ -z "${COMMUNITY_SCRIPTS_BASE_URL:-}" ]]; then
-    COMMUNITY_SCRIPTS_BASE_URL="https://raw.githubusercontent.com/community-scripts/ProxmoxVE/main"
-fi
+# ------------------------------------------------------------------------------
+# explain_exit_code()
+#
+# - Maps numeric exit codes to human-readable error descriptions
+# - Supports:
+#   * Generic/Shell errors (1, 2, 126, 127, 128, 130, 137, 139, 143)
+#   * Package manager errors (APT, DPKG: 100, 101, 255)
+#   * Node.js/npm errors (243-249, 254)
+#   * Python/pip/uv errors (210-212)
+#   * PostgreSQL errors (231-234)
+#   * MySQL/MariaDB errors (241-244)
+#   * MongoDB errors (251-254)
+#   * Proxmox custom codes (200-231)
+# - Returns description string for given exit code
+# - Shared function with error_handler.func for consistency
+# ------------------------------------------------------------------------------
+explain_exit_code() {
+    local code="$1"
+    case "$code" in
+    # --- Generic / Shell ---
+    1) echo "General error / Operation not permitted" ;;
+    2) echo "Misuse of shell builtins (e.g. syntax error)" ;;
+    126) echo "Command invoked cannot execute (permission problem?)" ;;
+    127) echo "Command not found" ;;
+    128) echo "Invalid argument to exit" ;;
+    130) echo "Terminated by Ctrl+C (SIGINT)" ;;
+    137) echo "Killed (SIGKILL / Out of memory?)" ;;
+    139) echo "Segmentation fault (core dumped)" ;;
+    143) echo "Terminated (SIGTERM)" ;;
 
-if ! declare -f explain_exit_code >/dev/null 2>&1; then
-    source <(curl -fsSL "${COMMUNITY_SCRIPTS_BASE_URL}/misc/error_handler.func") || {
-        echo "Failed to load error_handler.func" >&2
-        return 1
-    }
-fi
+    # --- Package manager / APT / DPKG ---
+    100) echo "APT: Package manager error (broken packages / dependency problems)" ;;
+    101) echo "APT: Configuration error (bad sources.list, malformed config)" ;;
+    255) echo "DPKG: Fatal internal error" ;;
+
+    # --- Node.js / npm / pnpm / yarn ---
+    243) echo "Node.js: Out of memory (JavaScript heap out of memory)" ;;
+    245) echo "Node.js: Invalid command-line option" ;;
+    246) echo "Node.js: Internal JavaScript Parse Error" ;;
+    247) echo "Node.js: Fatal internal error" ;;
+    248) echo "Node.js: Invalid C++ addon / N-API failure" ;;
+    249) echo "Node.js: Inspector error" ;;
+    254) echo "npm/pnpm/yarn: Unknown fatal error" ;;
+
+    # --- Python / pip / uv ---
+    210) echo "Python: Virtualenv / uv environment missing or broken" ;;
+    211) echo "Python: Dependency resolution failed" ;;
+    212) echo "Python: Installation aborted (permissions or EXTERNALLY-MANAGED)" ;;
+
+    # --- PostgreSQL ---
+    231) echo "PostgreSQL: Connection failed (server not running / wrong socket)" ;;
+    232) echo "PostgreSQL: Authentication failed (bad user/password)" ;;
+    233) echo "PostgreSQL: Database does not exist" ;;
+    234) echo "PostgreSQL: Fatal error in query / syntax" ;;
+
+    # --- MySQL / MariaDB ---
+    241) echo "MySQL/MariaDB: Connection failed (server not running / wrong socket)" ;;
+    242) echo "MySQL/MariaDB: Authentication failed (bad user/password)" ;;
+    243) echo "MySQL/MariaDB: Database does not exist" ;;
+    244) echo "MySQL/MariaDB: Fatal error in query / syntax" ;;
+
+    # --- MongoDB ---
+    251) echo "MongoDB: Connection failed (server not running)" ;;
+    252) echo "MongoDB: Authentication failed (bad user/password)" ;;
+    253) echo "MongoDB: Database not found" ;;
+    254) echo "MongoDB: Fatal query error" ;;
+
+    # --- Proxmox Custom Codes ---
+    200) echo "Custom: Failed to create lock file" ;;
+    203) echo "Custom: Missing CTID variable" ;;
+    204) echo "Custom: Missing PCT_OSTYPE variable" ;;
+    205) echo "Custom: Invalid CTID (<100)" ;;
+    209) echo "Custom: Container creation failed" ;;
+    210) echo "Custom: Cluster not quorate" ;;
+    214) echo "Custom: Not enough storage space" ;;
+    215) echo "Custom: Container ID not listed" ;;
+    216) echo "Custom: RootFS entry missing in config" ;;
+    217) echo "Custom: Storage does not support rootdir" ;;
+    220) echo "Custom: Unable to resolve template path" ;;
+    222) echo "Custom: Template download failed after 3 attempts" ;;
+    223) echo "Custom: Template not available after download" ;;
+    231) echo "Custom: LXC stack upgrade/retry failed" ;;
+
+    # --- Default ---
+    *) echo "Unknown error" ;;
+    esac
+}
 
 # ==============================================================================
 # SECTION 2: TELEMETRY FUNCTIONS
diff --git a/misc/build.func b/misc/build.func
index 72b1fb9d5..b0b0404cd 100644
--- a/misc/build.func
+++ b/misc/build.func
@@ -1552,14 +1552,11 @@ advanced_settings() {
 # diagnostics_check()
 #
 # - Ensures diagnostics config file exists at /usr/local/community-scripts/diagnostics
-<<<<<<< Updated upstream
 # - Asks user whether to send anonymous diagnostic data
 # - Saves DIAGNOSTICS=yes/no in the config file
-=======
 # - Creates file if missing with default DIAGNOSTICS=yes
 # - Reads current diagnostics setting from file
 # - Sets global DIAGNOSTICS variable for API telemetry opt-in/out
->>>>>>> Stashed changes
 # ------------------------------------------------------------------------------
 diagnostics_check() {
   if ! [ -d "/usr/local/community-scripts" ]; then