feat(gemini): improve request context for support and compatibility

agent/gemini_native_adapter.py

@@ -32,6 +32,13 @@
 
 logger = logging.getLogger(__name__)
 
+try:
+    import hermes_cli as _hermes_cli
+
+    _HERMES_VERSION = str(_hermes_cli.__version__)
+except Exception:
+    _HERMES_VERSION = "0.0.0"
+
 DEFAULT_GEMINI_BASE_URL = "https://generativelanguage.googleapis.com/v1beta"
 
 # Published max output-token ceiling shared by every current Gemini text model
@@ -99,7 +106,10 @@ def probe_gemini_tier(
                 url,
                 params={"key": key},
                 json=payload,
-                headers={"Content-Type": "application/json"},
+                headers={
+                    "Content-Type": "application/json",
+                    "X-Goog-Api-Client": f"hermes-agent/{_HERMES_VERSION}",
+                },
             )
     except Exception as exc:
         logger.debug("probe_gemini_tier: network error: %s", exc)
@@ -901,7 +911,11 @@ def _headers(self) -> Dict[str, str]:
             "Content-Type": "application/json",
             "Accept": "application/json",
             "x-goog-api-key": self.api_key,
-            "User-Agent": "hermes-agent (gemini-native)",
+            # Include Hermes client context following Gemini's partner
+            # integration guidance.
+            # See https://ai.google.dev/gemini-api/docs/partner-integration
+            "User-Agent": f"hermes-agent/{_HERMES_VERSION} (gemini-native)",
+            "X-Goog-Api-Client": f"hermes-agent/{_HERMES_VERSION}",
         }
         headers.update(self._default_headers)
         return headers

hermes_cli/models.py

@@ -3574,6 +3574,8 @@ def probe_api_models(
 
     tried: list[str] = []
     headers: dict[str, str] = {"User-Agent": _HERMES_USER_AGENT}
+    if urllib.parse.urlparse(normalized).hostname == "generativelanguage.googleapis.com":
+        headers["X-Goog-Api-Client"] = f"hermes-agent/{_HERMES_VERSION}"
     if api_key and api_mode == "anthropic_messages":
         headers["x-api-key"] = api_key
         headers["anthropic-version"] = "2023-06-01"

scripts/release.py

@@ -758,6 +758,7 @@
     "bzarnitz13@gmail.com": "Beandon13",
     "tony@tonysimons.dev": "asimons81",
     "jetha@google.com": "jethac",
+    "vishal.dharm@gmail.com": "vishal-dharm",
     "jani@0xhoneyjar.xyz": "deep-name",
     # LINE messaging plugin (synthesis PR)
     "32443648+leepoweii@users.noreply.github.com": "leepoweii",

tests/agent/test_gemini_native_adapter.py

@@ -461,3 +461,53 @@ def test_explicit_max_tokens_is_respected():
 
     req = build_gemini_request(messages=[{"role": "user", "content": "hi"}], max_tokens=4096)
     assert req["generationConfig"]["maxOutputTokens"] == 4096
+
+
+# ---------------------------------------------------------------------------
+# X-Goog-Api-Client header tests
+# ---------------------------------------------------------------------------
+
+
+def test_x_goog_api_client_header_is_set():
+    """The X-Goog-Api-Client header should be set on inference requests."""
+    from agent.gemini_native_adapter import GeminiNativeClient
+
+    client = GeminiNativeClient(api_key="fake-key", model="gemini-2.0-flash")
+    headers = client._headers()
+
+    assert "X-Goog-Api-Client" in headers, "X-Goog-Api-Client header missing"
+    assert "hermes-agent/" in headers["X-Goog-Api-Client"], (
+        "hermes-agent not found in X-Goog-Api-Client header"
+    )
+
+
+def test_x_goog_api_client_header_format():
+    """Header value should be 'hermes-agent/<version>' matching the package version."""
+    from agent.gemini_native_adapter import GeminiNativeClient, _HERMES_VERSION
+
+    client = GeminiNativeClient(api_key="fake-key", model="gemini-2.0-flash")
+    headers = client._headers()
+
+    expected = f"hermes-agent/{_HERMES_VERSION}"
+    assert headers["X-Goog-Api-Client"] == expected
+
+
+def test_user_agent_contains_version():
+    """User-Agent should include the hermes-agent version."""
+    from agent.gemini_native_adapter import GeminiNativeClient, _HERMES_VERSION
+
+    client = GeminiNativeClient(api_key="fake-key", model="gemini-2.0-flash")
+    headers = client._headers()
+
+    assert f"hermes-agent/{_HERMES_VERSION}" in headers["User-Agent"]
+
+
+def test_hermes_version_is_valid():
+    """_HERMES_VERSION should be a non-empty string."""
+    from agent.gemini_native_adapter import _HERMES_VERSION
+
+    assert isinstance(_HERMES_VERSION, str)
+    assert len(_HERMES_VERSION) > 0
+    assert _HERMES_VERSION != "0.0.0", (
+        "Version should resolve from hermes_cli.__version__, not the fallback"
+    )

tests/hermes_cli/test_model_validation.py

@@ -942,3 +942,33 @@ def test_probe_user_agent_sent_without_api_key(self):
         assert ua and ua.startswith("hermes-cli/")
         # No Authorization was set, but UA must still be present.
         assert req.get_header("Authorization") is None
+
+    def test_probe_sends_client_context_to_gemini(self):
+        from unittest.mock import patch
+        from hermes_cli.models import _HERMES_VERSION
+
+        body = b'{"data":[]}'
+        with patch(
+            "hermes_cli.models.urllib.request.urlopen",
+            return_value=self._make_mock_response(body),
+        ) as mock_urlopen:
+            probe_api_models(
+                "gemini-key",
+                "https://generativelanguage.googleapis.com/v1beta/openai",
+            )
+
+        req = mock_urlopen.call_args[0][0]
+        assert req.get_header("X-goog-api-client") == f"hermes-agent/{_HERMES_VERSION}"
+
+    def test_probe_omits_gemini_client_context_for_other_providers(self):
+        from unittest.mock import patch
+
+        body = b'{"data":[]}'
+        with patch(
+            "hermes_cli.models.urllib.request.urlopen",
+            return_value=self._make_mock_response(body),
+        ) as mock_urlopen:
+            probe_api_models("provider-key", "https://api.example.com/v1")
+
+        req = mock_urlopen.call_args[0][0]
+        assert req.get_header("X-goog-api-client") is None

tests/tools/test_tts_gemini.py

@@ -115,6 +115,19 @@ def test_wav_output_fast_path(self, tmp_path, monkeypatch, mock_gemini_response,
         # Audio payload should match the PCM we put in
         assert data[44:] == fake_pcm_bytes
 
+    def test_x_goog_api_client_header_is_set(self, tmp_path, monkeypatch, mock_gemini_response):
+        """Gemini TTS requests should include Hermes client context."""
+        from tools.tts_tool import _generate_gemini_tts
+
+        monkeypatch.setenv("GEMINI_API_KEY", "test-key")
+
+        with patch("requests.post", return_value=mock_gemini_response) as mock_post:
+            _generate_gemini_tts("Hi", str(tmp_path / "test.wav"), {})
+
+        headers = mock_post.call_args[1]["headers"]
+        assert "X-Goog-Api-Client" in headers
+        assert headers["X-Goog-Api-Client"].startswith("hermes-agent/")
+
     def test_default_voice_and_model(self, tmp_path, monkeypatch, mock_gemini_response):
         from tools.tts_tool import (
             DEFAULT_GEMINI_TTS_MODEL,

tools/tts_tool.py

@@ -1732,11 +1732,24 @@ def _generate_gemini_tts(text: str, output_path: str, tts_config: Dict[str, Any]
         },
     }
 
+    try:
+        import hermes_cli as _hermes_cli
+
+        _hermes_version = str(_hermes_cli.__version__)
+    except Exception:
+        _hermes_version = "0.0.0"
+
     endpoint = f"{base_url}/models/{model}:generateContent"
     response = requests.post(
         endpoint,
         params={"key": api_key},
-        headers={"Content-Type": "application/json"},
+        headers={
+            "Content-Type": "application/json",
+            # Include Hermes client context following Gemini's partner
+            # integration guidance:
+            # https://ai.google.dev/gemini-api/docs/partner-integration
+            "X-Goog-Api-Client": f"hermes-agent/{_hermes_version}",
+        },
         json=payload,
         timeout=60,
     )