Fix unsupported MCP tools param (#8610)

openhands/agenthub/codeact_agent/codeact_agent.py

@@ -10,6 +10,7 @@ if TYPE_CHECKING:
     from openhands.events.action import Action
     from openhands.llm.llm import ModelResponse
 
+from openhands.llm.llm_utils import check_tools
 import openhands.agenthub.codeact_agent.function_calling as codeact_function_calling
 from openhands.agenthub.codeact_agent.tools.bash import create_cmd_run_tool
 from openhands.agenthub.codeact_agent.tools.browser import BrowserTool
@@ -185,26 +186,7 @@ class CodeActAgent(Agent):
         params: dict = {
             'messages': self.llm.format_messages_for_llm(messages),
         }
-        params['tools'] = self.tools
-
-        # Special handling for Gemini model which doesn't support default fields
-        if self.llm.config.model == 'gemini-2.5-pro-preview-03-25':
-            logger.info(
-                f'Removing the default fields from tools for {self.llm.config.model} '
-                "since it doesn't support them and the request would crash."
-            )
-            # prevent mutation of input tools
-            params['tools'] = copy.deepcopy(params['tools'])
-            # Strip off default fields that cause errors with gemini-preview
-            for tool in params['tools']:
-                if 'function' in tool and 'parameters' in tool['function']:
-                    if 'properties' in tool['function']['parameters']:
-                        for prop_name, prop in tool['function']['parameters'][
-                            'properties'
-                        ].items():
-                            if 'default' in prop:
-                                del prop['default']
-        # log to litellm proxy if possible
+        params['tools'] = check_tools(self.tools, self.llm.config)
         params['extra_body'] = {'metadata': state.to_llm_metadata(agent_name=self.name)}
         response = self.llm.completion(**params)
         logger.debug(f'Response from LLM: {response}')

openhands/llm/llm.py

@@ -279,9 +279,6 @@ class LLM(RetryMixin, DebugMixin):
             # Record start time for latency measurement
             start_time = time.time()
             # we don't support streaming here, thus we get a ModelResponse
-            logger.debug(
-                f'LLM: calling litellm completion with model: {self.config.model}, base_url: {self.config.base_url}, args: {args}, kwargs: {kwargs}'
-            )
             resp: ModelResponse = self._completion_unwrapped(*args, **kwargs)
 
             # Calculate and record latency

openhands/llm/llm_utils.py

@@ -0,0 +1,44 @@
+import copy
+from typing import TYPE_CHECKING
+
+from openhands.core.config import LLMConfig
+from openhands.core.logger import openhands_logger as logger
+
+if TYPE_CHECKING:
+    from litellm import ChatCompletionToolParam
+
+
+def check_tools(
+    tools: list['ChatCompletionToolParam'], llm_config: LLMConfig
+) -> list['ChatCompletionToolParam']:
+    """Checks and modifies tools for compatibility with the current LLM."""
+    # Special handling for Gemini models which don't support default fields and have limited format support
+    if 'gemini' in llm_config.model.lower():
+        logger.info(
+            f'Removing default fields and unsupported formats from tools for Gemini model {llm_config.model} '
+            "since Gemini models have limited format support (only 'enum' and 'date-time' for STRING types)."
+        )
+        # prevent mutation of input tools
+        checked_tools = copy.deepcopy(tools)
+        # Strip off default fields and unsupported formats that cause errors with gemini-preview
+        for tool in checked_tools:
+            if 'function' in tool and 'parameters' in tool['function']:
+                if 'properties' in tool['function']['parameters']:
+                    for prop_name, prop in tool['function']['parameters'][
+                        'properties'
+                    ].items():
+                        # Remove default fields
+                        if 'default' in prop:
+                            del prop['default']
+
+                        # Remove format fields for STRING type parameters if the format is unsupported
+                        # Gemini only supports 'enum' and 'date-time' formats for STRING type
+                        if prop.get('type') == 'string' and 'format' in prop:
+                            supported_formats = ['enum', 'date-time']
+                            if prop['format'] not in supported_formats:
+                                logger.info(
+                                    f'Removing unsupported format "{prop["format"]}" for STRING parameter "{prop_name}"'
+                                )
+                                del prop['format']
+        return checked_tools
+    return tools