fix: validate label IDs in ha_manage_entity_labels to prevent silent failures (#486)

* fix: validate label IDs in ha_manage_entity_labels to prevent silent failures

Add validation to ha_manage_entity_labels that checks if all label IDs exist
before attempting assignment. This prevents the silent failure bug where the
tool would report success but fail to apply non-existent labels AND hide all
existing labels in the UI.

Changes:
- Add label ID validation before entity operations in ha_manage_entity_labels
- Fetch available labels from label registry via WebSocket
- Return clear error message listing non-existent label IDs
- Provide helpful suggestions to use ha_config_get_label() or ha_config_set_label()
- Add comprehensive E2E tests for label validation scenarios

Fixes #475

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

* refactor: improve robustness of label validation

Address Gemini Code Assist review suggestions:
- Add type checking for label list items to prevent AttributeError
- Improve test assertions to verify exact invalid label lists
- Ensure both helper tool suggestions are validated in tests

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

---------

Co-authored-by: Claude Sonnet 4.5 <noreply@anthropic.com>

Author: julienld

src/ha_mcp/tools/tools_labels.py

@@ -675,6 +675,46 @@ async def ha_manage_entity_labels(
             # Deduplicate labels
             parsed_labels = list(set(parsed_labels))
 
+            # Validate that all label IDs exist before attempting assignment
+            if parsed_labels:
+                try:
+                    # Fetch all available labels via WebSocket
+                    message: dict[str, Any] = {
+                        "type": "config/label_registry/list",
+                    }
+                    label_list_result = await client.send_websocket_message(message)
+
+                    if not label_list_result.get("success"):
+                        return {
+                            "success": False,
+                            "error": "Failed to fetch available labels for validation",
+                            "suggestions": ["Check Home Assistant connection"],
+                        }
+
+                    available_labels = label_list_result.get("result", [])
+                    available_label_ids = {lbl['label_id'] for lbl in available_labels if isinstance(lbl, dict) and 'label_id' in lbl}
+
+                    # Check for non-existent labels
+                    invalid_labels = [lbl for lbl in parsed_labels if lbl not in available_label_ids]
+
+                    if invalid_labels:
+                        return {
+                            "success": False,
+                            "error": f"Labels do not exist: {', '.join(invalid_labels)}",
+                            "invalid_labels": invalid_labels,
+                            "suggestions": [
+                                "Use ha_config_get_label() to see all available labels",
+                                "Create missing labels with ha_config_set_label()",
+                            ],
+                        }
+                except Exception as e:
+                    logger.error(f"Error validating label IDs: {e}")
+                    return {
+                        "success": False,
+                        "error": f"Failed to validate label IDs: {str(e)}",
+                        "suggestions": ["Check Home Assistant connection"],
+                    }
+
             # Coerce parallel parameter
             parallel_bool = coerce_bool_param(parallel, "parallel", default=True)
             if parallel_bool is None:

tests/addon/test_addon_structure.py

@@ -3,7 +3,6 @@
 import os
 import stat
 import yaml
-import pytest
 
 try:
     import tomllib  # Python 3.11+

tests/initial_test_state/custom_components/hacs/base.py

@@ -61,7 +61,6 @@
 from .repositories import REPOSITORY_CLASSES
 from .repositories.base import HACS_MANIFEST_KEYS_TO_EXPORT, REPOSITORY_KEYS_TO_EXPORT
 from .utils.file_system import async_exists
-from .utils.json import json_loads
 from .utils.logger import LOGGER
 from .utils.queue_manager import QueueManager
 from .utils.store import async_load_from_store, async_save_to_store

tests/initial_test_state/custom_components/hacs/data_client.py

@@ -2,7 +2,6 @@
 
 from __future__ import annotations
 
-import asyncio
 from typing import Any
 
 from aiohttp import ClientSession, ClientTimeout

tests/initial_test_state/custom_components/hacs/repositories/base.py

@@ -34,7 +34,6 @@
 from ..utils.decorator import concurrent
 from ..utils.file_system import async_exists, async_remove, async_remove_directory
 from ..utils.filters import filter_content_return_one_of_type
-from ..utils.github_graphql_query import GET_REPOSITORY_RELEASES
 from ..utils.json import json_loads
 from ..utils.logger import LOGGER
 from ..utils.path import is_safe

tests/initial_test_state/custom_components/hacs/repositories/integration.py

@@ -180,7 +180,7 @@ async def async_get_integration_manifest(self, ref: str = None) -> dict[str, Any
             else f"{self.content.path.remote}/{RepositoryFile.MAINIFEST_JSON}"
         )
 
-        if not manifest_path in (x.full_path for x in self.tree):
+        if manifest_path not in (x.full_path for x in self.tree):
             raise HacsException(f"No {RepositoryFile.MAINIFEST_JSON} file found '{manifest_path}'")
 
         response = await self.hacs.async_github_api_method(

tests/src/e2e/conftest.py

@@ -74,7 +74,6 @@ def _ensure_hacs_frontend(initial_state_path: Path) -> None:
     HACS requires the frontend (~51MB) to be present to fully initialize.
     This is not committed to git to keep the repo size manageable.
     """
-    import subprocess
     import tarfile
     import urllib.request
 

tests/src/e2e/workflows/automation/test_lifecycle.py

@@ -8,7 +8,6 @@
 and production environments. Entity references are dynamically discovered.
 """
 
-import asyncio
 import logging
 
 import pytest

tests/src/e2e/workflows/automation/test_traces.py

@@ -5,7 +5,6 @@
 Verifies that ha_get_automation_traces returns non-empty traces after automation runs.
 """
 
-import asyncio
 import logging
 
 import pytest

tests/src/e2e/workflows/blueprints/test_blueprints.py

@@ -9,7 +9,6 @@
 and production environments. Blueprint availability may vary.
 """
 
-import asyncio
 import logging
 
 import pytest
@@ -380,7 +379,7 @@ async def test_blueprint_automation_lifecycle(mcp_client):
             error_msg = str(create_result.get("error", {}).get("message", ""))
             # If error is about missing blueprint inputs, our validation passed! HA rejected it.
             if "Missing input" in error_msg or "input" in error_msg.lower():
-                logger.info(f"✅ Our validation passed (config reached HA), HA rejected due to missing blueprint inputs as expected")
+                logger.info("✅ Our validation passed (config reached HA), HA rejected due to missing blueprint inputs as expected")
                 logger.info("✅ Blueprint automation lifecycle test completed (validation works)")
                 return
             # If error is about missing trigger/action, our fix didn't work