scope Google TTS credentials safely

tests/tools/test_google_tts_scoped_key.py

@@ -0,0 +1,36 @@
+from tools.audio.google_tts import GoogleTTS
+from tools.google_credentials import has_google_credentials
+
+
+def test_tts_only_key_does_not_enable_shared_google_providers(monkeypatch):
+    monkeypatch.setenv("GOOGLE_TTS_API_KEY", "test-tts-only-key")
+    monkeypatch.delenv("GOOGLE_API_KEY", raising=False)
+    monkeypatch.delenv("GEMINI_API_KEY", raising=False)
+    monkeypatch.delenv("GOOGLE_APPLICATION_CREDENTIALS", raising=False)
+
+    assert GoogleTTS().get_status().value == "available"
+    assert has_google_credentials() is False
+
+
+def test_tts_key_uses_header_and_is_redacted_from_errors(monkeypatch, tmp_path):
+    import requests
+
+    secret = "test-production-shaped-tts-key"
+    monkeypatch.setenv("GOOGLE_TTS_API_KEY", secret)
+    monkeypatch.delenv("GOOGLE_API_KEY", raising=False)
+    monkeypatch.delenv("GEMINI_API_KEY", raising=False)
+    monkeypatch.delenv("GOOGLE_APPLICATION_CREDENTIALS", raising=False)
+
+    def fail_request(url, **kwargs):
+        assert kwargs["headers"]["x-goog-api-key"] == secret
+        assert "params" not in kwargs
+        raise requests.HTTPError(f"403 for {url}?key={secret}")
+
+    monkeypatch.setattr(requests, "post", fail_request)
+    result = GoogleTTS().execute(
+        {"text": "safe test sentence", "output_path": str(tmp_path / "speech.mp3")}
+    )
+
+    assert result.success is False
+    assert secret not in result.error
+    assert "[REDACTED]" in result.error

tools/audio/google_tts.py

@@ -27,7 +27,6 @@ from tools.base_tool import (
 from tools.google_credentials import (
     get_access_token,
     service_account_configured,
-    has_google_credentials,
 )
 
 
@@ -44,7 +43,8 @@ class GoogleTTS(BaseTool):
 
     dependencies = []
     install_instructions = (
-        "Auth option A — API key: set GOOGLE_API_KEY (or GEMINI_API_KEY) to a\n"
+        "Auth option A — TTS-only API key: set GOOGLE_TTS_API_KEY.\n"
+        "  GOOGLE_API_KEY or GEMINI_API_KEY remain supported for broader Google setups.\n"
         "  Google Cloud API key with Text-to-Speech enabled.\n"
         "  Enable the API at https://console.cloud.google.com/apis/library/texttospeech.googleapis.com\n"
         "Auth option B — service account: set GOOGLE_APPLICATION_CREDENTIALS to the\n"
@@ -149,12 +149,16 @@ class GoogleTTS(BaseTool):
     }
 
     def _get_api_key(self) -> str | None:
-        return os.environ.get("GOOGLE_API_KEY") or os.environ.get("GEMINI_API_KEY")
+        return (
+            os.environ.get("GOOGLE_TTS_API_KEY")
+            or os.environ.get("GOOGLE_API_KEY")
+            or os.environ.get("GEMINI_API_KEY")
+        )
 
     def get_status(self) -> ToolStatus:
         # Available via either an API key or a service-account JSON. Both paths
         # are honoured by execute() — so this no longer over-reports.
-        if has_google_credentials():
+        if self._get_api_key() or service_account_configured():
             return ToolStatus.AVAILABLE
         return ToolStatus.UNAVAILABLE
 
@@ -204,7 +208,11 @@ class GoogleTTS(BaseTool):
         try:
             result = self._generate(inputs, api_key=api_key, bearer_token=bearer_token)
         except Exception as exc:
-            return ToolResult(success=False, error=f"Google TTS failed: {exc}")
+            safe_error = str(exc)
+            for credential in (api_key, bearer_token):
+                if credential:
+                    safe_error = safe_error.replace(credential, "[REDACTED]")
+            return ToolResult(success=False, error=f"Google TTS failed: {safe_error}")
 
         result.duration_seconds = round(time.time() - start, 2)
         result.cost_usd = self.estimate_cost(inputs)
@@ -266,16 +274,14 @@ class GoogleTTS(BaseTool):
         url = f"https://texttospeech.googleapis.com/{api_version}/text:synthesize"
 
         headers = {"Content-Type": "application/json"}
-        params: dict[str, str] = {}
         if bearer_token:
             headers["Authorization"] = f"Bearer {bearer_token}"
         elif api_key:
-            params["key"] = api_key
+            headers["x-goog-api-key"] = api_key
 
         response = requests.post(
             url,
             headers=headers,
-            params=params,
             json=payload,
             timeout=120,
         )