Sanitize MCP FunctionDeclarations to workaround Vertex bug (#1330)

This commit is contained in:
Tommaso Sciortino 2025-06-23 09:13:53 -07:00 committed by GitHub
parent 7b39dd8b28
commit 07880d43d2
No known key found for this signature in database
GPG Key ID: B5690EEEBB952194
2 changed files with 115 additions and 2 deletions

View File

@ -14,7 +14,8 @@ import {
afterEach,
Mocked,
} from 'vitest';
import { discoverMcpTools } from './mcp-client.js';
import { discoverMcpTools, sanatizeParameters } from './mcp-client.js';
import { Schema, Type } from '@google/genai';
import { Config, MCPServerConfig } from '../config/config.js';
import { DiscoveredMCPTool } from './mcp-tool.js';
import { Client } from '@modelcontextprotocol/sdk/client/index.js';
@ -536,3 +537,87 @@ describe('discoverMcpTools', () => {
expect(lastClientInstance?.onerror).toEqual(expect.any(Function));
});
});
describe('sanatizeParameters', () => {
it('should do nothing for an undefined schema', () => {
const schema = undefined;
sanatizeParameters(schema);
});
it('should remove default when anyOf is present', () => {
const schema: Schema = {
anyOf: [{ type: Type.STRING }, { type: Type.NUMBER }],
default: 'hello',
};
sanatizeParameters(schema);
expect(schema.default).toBeUndefined();
});
it('should recursively sanatize items in anyOf', () => {
const schema: Schema = {
anyOf: [
{
anyOf: [{ type: Type.STRING }],
default: 'world',
},
{ type: Type.NUMBER },
],
};
sanatizeParameters(schema);
expect(schema.anyOf![0].default).toBeUndefined();
});
it('should recursively sanatize items in items', () => {
const schema: Schema = {
items: {
anyOf: [{ type: Type.STRING }],
default: 'world',
},
};
sanatizeParameters(schema);
expect(schema.items!.default).toBeUndefined();
});
it('should recursively sanatize items in properties', () => {
const schema: Schema = {
properties: {
prop1: {
anyOf: [{ type: Type.STRING }],
default: 'world',
},
},
};
sanatizeParameters(schema);
expect(schema.properties!.prop1.default).toBeUndefined();
});
it('should handle complex nested schemas', () => {
const schema: Schema = {
properties: {
prop1: {
items: {
anyOf: [{ type: Type.STRING }],
default: 'world',
},
},
prop2: {
anyOf: [
{
properties: {
nestedProp: {
anyOf: [{ type: Type.NUMBER }],
default: 123,
},
},
},
],
},
},
};
sanatizeParameters(schema);
expect(schema.properties!.prop1.items!.default).toBeUndefined();
const nestedProp =
schema.properties!.prop2.anyOf![0].properties!.nestedProp;
expect(nestedProp?.default).toBeUndefined();
});
});

View File

@ -11,7 +11,12 @@ import { StreamableHTTPClientTransport } from '@modelcontextprotocol/sdk/client/
import { parse } from 'shell-quote';
import { MCPServerConfig } from '../config/config.js';
import { DiscoveredMCPTool } from './mcp-tool.js';
import { CallableTool, FunctionDeclaration, mcpToTool } from '@google/genai';
import {
CallableTool,
FunctionDeclaration,
mcpToTool,
Schema,
} from '@google/genai';
import { ToolRegistry } from './tool-registry.js';
export const MCP_DEFAULT_TIMEOUT_MSEC = 10 * 60 * 1000; // default to 10 minutes
@ -299,6 +304,8 @@ async function connectAndDiscover(
toolNameForModel.slice(0, 28) + '___' + toolNameForModel.slice(-32);
}
sanatizeParameters(funcDecl.parameters);
// Ensure parameters is a valid JSON schema object, default to empty if not.
const parameterSchema: Record<string, unknown> =
funcDecl.parameters && typeof funcDecl.parameters === 'object'
@ -354,3 +361,24 @@ async function connectAndDiscover(
}
}
}
export function sanatizeParameters(schema?: Schema) {
if (!schema) {
return;
}
if (schema.anyOf) {
// Vertex AI gets confused if both anyOf and default are set.
schema.default = undefined;
for (const item of schema.anyOf) {
sanatizeParameters(item);
}
}
if (schema.items) {
sanatizeParameters(schema.items);
}
if (schema.properties) {
for (const item of Object.values(schema.properties)) {
sanatizeParameters(item);
}
}
}