fix(otel): custom metrics coexistence, FastAPI HTTP metrics, and export fixes

agentex/pyproject.toml

@@ -30,6 +30,7 @@ dependencies = [
     "opentelemetry-api>=1.28.0",
     "opentelemetry-sdk>=1.28.0",
     "opentelemetry-exporter-otlp>=1.28.0",
+    "opentelemetry-instrumentation-fastapi>=0.49b0",
     "pyyaml>=6.0,<7",
 ]
 

agentex/src/api/app.py

@@ -38,7 +38,7 @@
 from src.config.environment_variables import EnvVarKeys
 from src.domain.exceptions import GenericException
 from src.utils.logging import make_logger
-from src.utils.otel_metrics import init_otel_metrics, shutdown_otel_metrics
+from src.utils.otel_metrics import configure_app_metrics, shutdown_otel_metrics
 
 logger = make_logger(__name__)
 
@@ -73,9 +73,6 @@ def __init__(
 
 @asynccontextmanager
 async def lifespan(_: FastAPI):
-    # Initialize OpenTelemetry metrics first (before dependencies register instruments)
-    init_otel_metrics()
-
     await dependencies.startup_global_dependencies()
     configure_statsd()
 
@@ -195,6 +192,9 @@ async def handle_unexpected(request, exc):
 fastapi_app.include_router(checkpoints.router)
 fastapi_app.include_router(task_retention.router)
 
+# Instrument before the first ASGI message; lifespan startup is too late.
+configure_app_metrics(fastapi_app)
+
 # Wrap FastAPI app with health check interceptor for sub-millisecond K8s probe responses.
 # This must be the outermost layer to bypass all middleware.
 # Export as `app` so existing uvicorn entry points (app:app) work without changes.