feat: add native Gemini 3 series adapter

agent/gemini_adapter.py

@@ -0,0 +1,90 @@
+"""Native Gemini 3 Series adapter for Hermes Agent.
+
+Leverages the google-genai SDK to provide sovereign access to Gemini's
+unique capabilities: Thinking (Reasoning) tokens, Search Grounding,
+and Maps Grounding.
+"""
+
+import logging
+import os
+from typing import Any, Dict, List, Optional, Union
+
+try:
+    from google import genai
+    from google.genai import types
+except ImportError:
+    genai = None  # type: ignore
+    types = None  # type: ignore
+
+logger = logging.getLogger(__name__)
+
+class GeminiAdapter:
+    def __init__(self, api_key: Optional[str] = None):
+        self.api_key = api_key or os.environ.get("GEMINI_API_KEY")
+        if not self.api_key:
+            logger.warning("GEMINI_API_KEY not found in environment.")
+        
+        if genai:
+            self.client = genai.Client(api_key=self.api_key)
+        else:
+            self.client = None
+
+    def generate(
+        self,
+        model: str,
+        prompt: str,
+        system_instruction: Optional[str] = None,
+        thinking: bool = False,
+        thinking_budget: int = 16000,
+        grounding: bool = False,
+        **kwargs
+    ) -> Dict[str, Any]:
+        if not self.client:
+            raise ImportError("google-genai SDK not installed. Run 'pip install google-genai'.")
+
+        config = {}
+        if system_instruction:
+            config["system_instruction"] = system_instruction
+        
+        if thinking:
+            # Gemini 3 series thinking config
+            config["thinking_config"] = {"include_thoughts": True}
+            # max_output_tokens includes thinking tokens
+            kwargs["max_output_tokens"] = kwargs.get("max_output_tokens", 32000) + thinking_budget
+
+        tools = []
+        if grounding:
+            tools.append({"google_search": {}})
+        
+        if tools:
+            config["tools"] = tools
+
+        response = self.client.models.generate_content(
+            model=model,
+            contents=prompt,
+            config=types.GenerateContentConfig(**config, **kwargs)
+        )
+
+        result = {
+            "text": response.text,
+            "usage": {
+                "prompt_tokens": response.usage_metadata.prompt_token_count,
+                "candidates_tokens": response.usage_metadata.candidates_token_count,
+                "total_tokens": response.usage_metadata.total_token_count,
+            }
+        }
+
+        # Extract thoughts if present
+        thoughts = []
+        for part in response.candidates[0].content.parts:
+            if hasattr(part, 'thought') and part.thought:
+                thoughts.append(part.thought)
+        
+        if thoughts:
+            result["thoughts"] = "\n".join(thoughts)
+
+        # Extract grounding metadata
+        if response.candidates[0].grounding_metadata:
+            result["grounding"] = response.candidates[0].grounding_metadata
+
+        return result