Filter catalog metrics by configurable tag (e.g., AIAgent.FoundryAI)

Add filter_tag support to catalog_export and webapp so only metrics
with the required tag are exported to YAML and displayed in UI.
Previously all 19+ metrics were exported regardless of relevance.

- Add has_tag() helper to transformer module
- catalog_export.py: filter_tag parameter from instance.yaml openmetadata config
- webapp/app.py: filter metrics in _load_metrics_from_catalog()
- 7 new tests (has_tag, filter_tag export, stale cleanup)

connectors/openmetadata/transformer.py

@@ -174,6 +174,20 @@ def extract_unit(raw_metric: Dict[str, Any]) -> str:
     return ""
 
 
+def has_tag(tags: List[Dict[str, Any]], tag_fqn: str) -> bool:
+    """
+    Check if a specific tag (by FQN) is present in the tag list.
+
+    Args:
+        tags: List of tag dicts from OpenMetadata
+        tag_fqn: Fully qualified tag name to check (e.g., "AIAgent.FoundryAI")
+
+    Returns:
+        True if the tag is found
+    """
+    return any(t.get("tagFQN", "") == tag_fqn for t in tags)
+
+
 def extract_tag_names(tags: List[Dict[str, Any]]) -> List[str]:
     """
     Extract simple tag names from OpenMetadata tag list.

src/catalog_export.py

@@ -29,6 +29,7 @@ from connectors.openmetadata.client import OpenMetadataClient
 from connectors.openmetadata.transformer import (
     extract_category,
     extract_grain,
+    has_tag,
     metric_to_yaml_dict,
     sanitize_filename,
     table_to_yaml_dict,
@@ -121,21 +122,24 @@ def export_metrics(
     client: OpenMetadataClient,
     docs_dir: Path,
     catalog_url: str,
+    filter_tag: str = "",
 ) -> int:
     """
     Export metrics from OpenMetadata to YAML files.
 
     For each metric:
     1. Fetches all metrics from catalog API
-    2. Transforms each to YAML-compatible dict
+    2. Filters by required tag (if configured)
-    3. Writes individual YAML files: {docs_dir}/metrics/{category}/{name}.yml
+    3. Transforms each to YAML-compatible dict
-    4. Writes index file: {docs_dir}/metrics/metrics.yml
+    4. Writes individual YAML files: {docs_dir}/metrics/{category}/{name}.yml
-    5. Cleans up stale auto-generated files
+    5. Writes index file: {docs_dir}/metrics/metrics.yml
+    6. Cleans up stale auto-generated files
 
     Args:
         client: Initialized OpenMetadata API client
         docs_dir: Base docs directory (e.g., /data/docs)
         catalog_url: Catalog URL for header comments
+        filter_tag: If set, only export metrics that have this tag (e.g., "AIAgent.FoundryAI")
 
     Returns:
         Number of metrics exported
@@ -151,6 +155,14 @@ def export_metrics(
 
     logger.info(f"Fetched {len(raw_metrics)} metrics from catalog")
 
+    # Filter by tag if configured
+    if filter_tag:
+        filtered = [m for m in raw_metrics if has_tag(m.get("tags", []), filter_tag)]
+        logger.info(
+            f"Tag filter '{filter_tag}': {len(filtered)}/{len(raw_metrics)} metrics matched"
+        )
+        raw_metrics = filtered
+
     # Track which files we write (for cleanup)
     written_files: set[Path] = set()
     index_entries: List[Dict[str, Any]] = []
@@ -400,9 +412,12 @@ def main() -> None:
         logger.warning(f"Failed to initialize OpenMetadata client: {e}")
         return
 
+    # Optional tag filter (only export metrics with this tag)
+    filter_tag = om_config.get("filter_tag", "").strip()
+
     try:
         # Export metrics
-        metrics_count = export_metrics(client, docs_dir, catalog_url)
+        metrics_count = export_metrics(client, docs_dir, catalog_url, filter_tag=filter_tag)
 
         # Export tables
         try:

tests/test_catalog_export.py

@@ -297,6 +297,52 @@ class TestExportMetrics:
         assert (docs / "metrics" / "finance" / "total_revenue.yml").exists()
         assert (docs / "metrics" / "product" / "active_users.yml").exists()
 
+    def test_export_metrics_filter_tag_keeps_matching(self, tmp_path: Path, mock_client):
+        """Only metrics with the filter_tag are exported."""
+        tagged = _make_raw_metric(name="M1", fqn="M1", category_tag="MetricCategory.finance")
+        tagged["tags"].append({"tagFQN": "AIAgent.FoundryAI", "name": "FoundryAI"})
+
+        untagged = _make_raw_metric(
+            name="Live Deals", fqn="LiveDeals", category_tag="MetricCategory.supply"
+        )
+
+        mock_client.get_metrics.return_value = [tagged, untagged]
+
+        docs = tmp_path / "docs"
+        count = export_metrics(mock_client, docs, CATALOG_URL, filter_tag="AIAgent.FoundryAI")
+
+        assert count == 1
+        assert (docs / "metrics" / "finance" / "m1.yml").exists()
+        assert not (docs / "metrics" / "supply").exists()
+
+    def test_export_metrics_filter_tag_empty_exports_all(self, tmp_path: Path, mock_client):
+        """Empty filter_tag means no filtering - all metrics exported."""
+        mock_client.get_metrics.return_value = [
+            _make_raw_metric(name="A", fqn="A"),
+            _make_raw_metric(name="B", fqn="B"),
+        ]
+
+        docs = tmp_path / "docs"
+        count = export_metrics(mock_client, docs, CATALOG_URL, filter_tag="")
+
+        assert count == 2
+
+    def test_export_metrics_filter_tag_cleans_stale_untagged(self, tmp_path: Path, mock_client):
+        """Stale files from previously-exported untagged metrics get cleaned up."""
+        tagged = _make_raw_metric(name="M1", fqn="M1", category_tag="MetricCategory.finance")
+        tagged["tags"].append({"tagFQN": "AIAgent.FoundryAI", "name": "FoundryAI"})
+        mock_client.get_metrics.return_value = [tagged]
+
+        docs = tmp_path / "docs"
+        stale_dir = docs / "metrics" / "general"
+        stale_dir.mkdir(parents=True)
+        stale = stale_dir / "livedeals.yml"
+        stale.write_text(AUTO_GENERATED_MARKER + "\nname: livedeals\n")
+
+        export_metrics(mock_client, docs, CATALOG_URL, filter_tag="AIAgent.FoundryAI")
+
+        assert not stale.exists()
+
 
 # ---------------------------------------------------------------------------
 # 4. export_tables

tests/test_openmetadata_transformer.py

@@ -15,6 +15,7 @@ from connectors.openmetadata.transformer import (
     extract_owners,
     extract_tag_names,
     extract_unit,
+    has_tag,
     metric_to_detail_dict,
     metric_to_display_dict,
     metric_to_yaml_dict,
@@ -331,6 +332,30 @@ class TestExtractUnit:
 # extract_tag_names
 # ===========================================================================
 
+class TestHasTag:
+    def test_has_tag_present(self):
+        """Returns True when tag with matching FQN is in the list."""
+        tags = [
+            {"tagFQN": "AIAgent.FoundryAI", "name": "FoundryAI"},
+            {"tagFQN": "Tier.Tier1"},
+        ]
+        assert has_tag(tags, "AIAgent.FoundryAI") is True
+
+    def test_has_tag_absent(self):
+        """Returns False when tag is not in the list."""
+        tags = [{"tagFQN": "Tier.Tier2"}]
+        assert has_tag(tags, "AIAgent.FoundryAI") is False
+
+    def test_has_tag_empty_list(self):
+        """Returns False for empty tag list."""
+        assert has_tag([], "AIAgent.FoundryAI") is False
+
+    def test_has_tag_partial_match(self):
+        """Does not match partial FQN."""
+        tags = [{"tagFQN": "AIAgent.FoundryAI_v2"}]
+        assert has_tag(tags, "AIAgent.FoundryAI") is False
+
+
 class TestExtractTagNames:
     def test_extract_tag_names_with_name_field(self):
         """Tags with 'name' field use that value."""

webapp/app.py

@@ -65,6 +65,7 @@ except ImportError:
 # Shared OpenMetadata transformer (catalog -> dict)
 try:
     from connectors.openmetadata.transformer import (
+        has_tag as _transformer_has_tag,
         metric_to_detail_dict as _transformer_metric_detail,
         metric_to_display_dict as _transformer_metric_display,
     )
@@ -81,6 +82,7 @@ logger = logging.getLogger(__name__)
 
 # Global catalog enricher (initialized in create_app)
 _catalog_enricher = None
+_catalog_filter_tag = ""
 
 
 def get_git_commit_hash() -> str:
@@ -122,6 +124,12 @@ def create_app() -> Flask:
             _catalog_enricher = CatalogEnricher(instance_config)
             if _catalog_enricher.enabled:
                 logger.info("OpenMetadata catalog enricher initialized")
+            # Store filter tag for metric filtering
+            global _catalog_filter_tag
+            om_config = instance_config.get("openmetadata", {})
+            _catalog_filter_tag = om_config.get("filter_tag", "").strip()
+            if _catalog_filter_tag:
+                logger.info(f"Catalog metric filter tag: {_catalog_filter_tag}")
         except Exception as e:
             logger.warning(f"Failed to initialize catalog enricher: {e}")
             _catalog_enricher = None
@@ -720,6 +728,13 @@ def _load_metrics_from_catalog() -> list:
             logger.debug("No metrics found in catalog")
             return []
 
+        # Filter by tag if configured
+        if _catalog_filter_tag and _TRANSFORMER_AVAILABLE:
+            raw_metrics = [
+                m for m in raw_metrics
+                if _transformer_has_tag(m.get("tags", []), _catalog_filter_tag)
+            ]
+
         # Parse each metric and group by category
         categories = {}
         for raw in raw_metrics: