✨ Detect when user is using agents

pyproject.toml

@@ -39,6 +39,7 @@ dependencies = [
     "sentry-sdk >= 2.20.0",
     "fastar >= 0.10.0",
     "detect-installer>=0.1.0",
+    "agent-detector>=1.1.0",
 ]
 
 [project.optional-dependencies]

src/fastapi_cloud_cli/utils/api.py

@@ -14,6 +14,7 @@
 
 import httpx
 import typer
+from agent_detector import detect_agent
 from pydantic import BaseModel, Field, TypeAdapter, ValidationError
 from rich_toolkit.progress import Progress
 from typing_extensions import ParamSpec
@@ -304,6 +305,15 @@ def get_http_error_hint(code: ErrorCode, *, auth_mode: AuthMode = "user") -> str
     return None
 
 
+def _get_user_agent() -> str:
+    user_agent = f"fastapi-cloud-cli/{__version__}"
+
+    if detection := detect_agent(minimum_confidence="high"):
+        user_agent = f"{user_agent} AI-Agent/{detection.agent}"
+
+    return user_agent
+
+
 class APIClient(httpx.Client):
     auth_mode: AuthMode
 
@@ -319,7 +329,7 @@ def __init__(self, use_deploy_token: bool = False) -> None:
             token = identity.user_token
             self.auth_mode = "user"
 
-        headers = {"User-Agent": f"fastapi-cloud-cli/{__version__}"}
+        headers = {"User-Agent": _get_user_agent()}
         if token:
             headers["Authorization"] = f"Bearer {token}"
 

tests/test_api_client.py

@@ -4,8 +4,10 @@
 import httpx
 import pytest
 import respx
+from agent_detector import DetectionResult
 from httpx import Response
 
+from fastapi_cloud_cli import __version__
 from fastapi_cloud_cli.utils.api import (
     STREAM_LOGS_MAX_RETRIES,
     APIClient,
@@ -30,6 +32,30 @@ def deployment_id() -> str:
     return "test-deployment-123"
 
 
+def test_api_client_reports_high_confidence_agent() -> None:
+    detection = DetectionResult("codex", "high", "environment", "CODEX_THREAD_ID")
+
+    with (
+        patch(
+            "fastapi_cloud_cli.utils.api.detect_agent", return_value=detection
+        ) as mock_detect_agent,
+        APIClient() as client,
+    ):
+        assert client.headers["User-Agent"] == (
+            f"fastapi-cloud-cli/{__version__} AI-Agent/codex"
+        )
+
+    mock_detect_agent.assert_called_once_with(minimum_confidence="high")
+
+
+def test_api_client_omits_unattributed_agent() -> None:
+    with (
+        patch("fastapi_cloud_cli.utils.api.detect_agent", return_value=None),
+        APIClient() as client,
+    ):
+        assert client.headers["User-Agent"] == f"fastapi-cloud-cli/{__version__}"
+
+
 @pytest.fixture
 def logs_route(respx_mock: respx.MockRouter, deployment_id: str) -> respx.Route:
     return respx_mock.get(f"/deployments/{deployment_id}/build-logs")