functionDeclarationToAnthropicTool ignores parametersJsonSchema, resulting in empty inputSchema for Claude MCP Tools #629
Description
When using MCP tools with the Claude model via the Google AI Java SDK, the method functionDeclarationToAnthropicTool fails to populate the tool's inputSchema. As a result, the generated Tool object always contains an empty properties map, even though the FunctionDeclaration object includes valid parameter schema data.
This effectively makes MCP tools unusable with Claude because no input schema is delivered to the model.
Actual Behavior
- parameters() is empty → the method skips schema processing
- parametersJsonSchema() contains the real schema but is ignored
- The resulting Tool has an empty inputSchema.properties map
- Claude receives a tool with no arguments → tools cannot be invoked properly
