From 1730861b609220bc691cf33e4c0efee833ad0bc0 Mon Sep 17 00:00:00 2001
From: Patrick Arminio <patrick.arminio@gmail.com>
Date: Wed, 19 Aug 2026 11:20:23 +0200
Subject: [PATCH] =?UTF-8?q?=E2=9C=A8=20Detect=20when=20user=20is=20using?=
 =?UTF-8?q?=20agents?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Shortcake-Parent: main
---
 pyproject.toml                     |  1 +
 src/fastapi_cloud_cli/utils/api.py | 12 +++++++++++-
 tests/test_api_client.py           | 26 ++++++++++++++++++++++++++
 uv.lock                            | 11 +++++++++++
 4 files changed, 49 insertions(+), 1 deletion(-)

diff --git a/pyproject.toml b/pyproject.toml
index 4e2572e9..c4b35205 100644
--- a/pyproject.toml
+++ b/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]
diff --git a/src/fastapi_cloud_cli/utils/api.py b/src/fastapi_cloud_cli/utils/api.py
index ec021eff..439a96cc 100644
--- a/src/fastapi_cloud_cli/utils/api.py
+++ b/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}"
 
diff --git a/tests/test_api_client.py b/tests/test_api_client.py
index bb3cf675..fa8a8271 100644
--- a/tests/test_api_client.py
+++ b/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")
diff --git a/uv.lock b/uv.lock
index 14a62420..67830857 100644
--- a/uv.lock
+++ b/uv.lock
@@ -8,6 +8,15 @@ resolution-markers = [
     "python_full_version < '3.13'",
 ]
 
+[[package]]
+name = "agent-detector"
+version = "1.1.0"
+source = { registry = "https://pypi.org/simple" }
+sdist = { url = "https://files.pythonhosted.org/packages/0a/51/2d6a4580f8a1ad26eca1f3849207e08d65a0df318188fe1a5b56cd868a1e/agent_detector-1.1.0.tar.gz", hash = "sha256:3428dc45713f93a115bd0b05c9dbbfdc72af70246064c07bd837a9a95cf016bc", size = 53720, upload-time = "2026-08-19T10:24:41.338Z" }
+wheels = [
+    { url = "https://files.pythonhosted.org/packages/c4/26/43b02c1cf72b12597dd7a3b49023918bded80edd733e00222f5a3ce42d85/agent_detector-1.1.0-py3-none-any.whl", hash = "sha256:c605af97afb894737dd798721b117d9bbc7aa491e02a676cd5916c79dc39a46d", size = 7966, upload-time = "2026-08-19T10:24:40.276Z" },
+]
+
 [[package]]
 name = "annotated-doc"
 version = "0.0.4"
@@ -276,6 +285,7 @@ wheels = [
 name = "fastapi-cloud-cli"
 source = { editable = "." }
 dependencies = [
+    { name = "agent-detector" },
     { name = "detect-installer" },
     { name = "fastar" },
     { name = "httpx" },
@@ -310,6 +320,7 @@ github-actions = [
 
 [package.metadata]
 requires-dist = [
+    { name = "agent-detector", specifier = ">=1.1.0" },
     { name = "detect-installer", specifier = ">=0.1.0" },
     { name = "fastar", specifier = ">=0.10.0" },
     { name = "httpx", specifier = ">=0.27.0" },