feat(genai): support model profiles (#1373)

Author: ccurme

libs/genai/langchain_google_genai/chat_models.py

@@ -6,6 +6,7 @@
 import json
 import logging
 import mimetypes
+import re
 import time
 import uuid
 import warnings
@@ -58,6 +59,8 @@
 from langchain_core.language_models import (
     LangSmithParams,
     LanguageModelInput,
+    ModelProfile,
+    ModelProfileRegistry,
     is_openai_data_block,
 )
 from langchain_core.language_models.chat_models import BaseChatModel
@@ -124,6 +127,7 @@
     ImageBytesLoader,
     image_bytes_to_b64_string,
 )
+from langchain_google_genai.data._profiles import _PROFILES
 
 from . import _genai_extension as genaix
 
@@ -137,6 +141,13 @@
     "__gemini_function_call_thought_signatures__"
 )
 
+_MODEL_PROFILES = cast("ModelProfileRegistry", _PROFILES)
+
+
+def _get_default_model_profile(model_name: str) -> ModelProfile:
+    default = _MODEL_PROFILES.get(model_name) or {}
+    return default.copy()
+
 
 def _bytes_to_base64(data: bytes) -> str:
     return base64.b64encode(data).decode("utf-8")
@@ -2070,6 +2081,14 @@ def async_client(self) -> v1betaGenerativeServiceAsyncClient:
             )
         return self.async_client_running
 
+    @model_validator(mode="after")
+    def _set_model_profile(self) -> Self:
+        """Set model profile if not overridden."""
+        if self.profile is None:
+            model_id = re.sub(r"-\d{3}$", "", self.model.replace("models/", ""))
+            self.profile = _get_default_model_profile(model_id)
+        return self
+
     @property
     def _identifying_params(self) -> dict[str, Any]:
         """Get the identifying parameters."""

libs/genai/langchain_google_genai/data/__init__.py

@@ -0,0 +1 @@
+"""Model profile data. All edits should be made in profile_augmentations.toml."""