JSON schema sent to Gemini is not compatible with Google

[ezyang]

What happened?

When using the codemcp server, LibreChat generates a schema to be sent to Google endpoints that fails validation. For reference, here is codemcp's single tool's signature:

@mcp.tool()
async def codemcp(
    subtool: str,
    *,
    path: str | None = None,
    content: str
    | dict
    | list
    | None = None,  # Allow any type, will be serialized to string if needed
    old_string: str | None = None,
    new_string: str | None = None,
    offset: int | None = None,
    limit: int | None = None,
    description: str | None = None,
    pattern: str | None = None,
    include: str | None = None,
    command: str | None = None,
    arguments: str | None = None,
    old_str: str | None = None,  # Added because Claude often hallucinates this
    new_str: str | None = None,  # Added because Claude often hallucinates this
    chat_id: str | None = None,  # Added for chat identification
    user_prompt: str | None = None,  # Added for InitProject commit message
    subject_line: str | None = None,  # Added for InitProject commit message
    reuse_head_chat_id: bool
    | None = None,  # Whether to reuse the chat ID from the HEAD commit
    thought: str | None = None,  # Added for Think tool
    mode: str | None = None,  # Added for Chmod tool
    commit_hash: str | None = None,  # Added for Git commit hash tracking
) -> str:

Version Information

150116e

Steps to Reproduce

1. Install codemcp in librechat
2. Do any prompt with codemcp tool enabled with a google model. I was using gemini-2.5-pro-preview-03-25

What browsers are you seeing the problem on?

No response

Relevant log output

{"attemptNumber":1,"level":"error","message":"[api/server/controllers/agents/client.js #sendCompletion] Operation aborted [GoogleGenerativeAI Error]: Error fetching from https://generativelanguage.googleapis.com/v1beta/models/gemini-2.5-pro-preview-03-25:streamGenerateContent?alt=sse: [400 Bad Request] * GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[content].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[commit_hash].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[subject_line].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[user_prompt].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[old_string].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[include].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[chat_id].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[mode].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[pattern].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[path].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[description].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[reuse_head_chat_id].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[command].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[thought].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[new_string].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[offset].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[arguments].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[new_str].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[limit].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[old_str].type: must be specified when not using one_of, any_of or all_of fields\n","pregelTaskId":"5ad96b5a-f7e2-5d62-a21a-99a8426fc4fb","retriesLeft":2,"stack":"Error: [GoogleGenerativeAI Error]: Error fetching from https://generativelanguage.googleapis.com/v1beta/models/gemini-2.5-pro-preview-03-25:streamGenerateContent?alt=sse: [400 Bad Request] * GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[content].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[commit_hash].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[subject_line].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[user_prompt].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[old_string].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[include].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[chat_id].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[mode].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[pattern].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[path].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[description].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[reuse_head_chat_id].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[command].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[thought].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[new_string].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[offset].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[arguments].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[new_str].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[limit].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[old_str].type: must be specified when not using one_of, any_of or all_of fields\n\n    at handleResponseNotOk (/Users/ezyang/Dev/LibreChat/node_modules/@google/generative-ai/dist/index.js:434:11)\n    at process.processTicksAndRejections (node:internal/process/task_queues:105:5)\n    at async makeRequest (/Users/ezyang/Dev/LibreChat/node_modules/@google/generative-ai/dist/index.js:403:9)\n    at async generateContentStream (/Users/ezyang/Dev/LibreChat/node_modules/@google/generative-ai/dist/index.js:862:22)\n    at async /Users/ezyang/Dev/LibreChat/node_modules/@langchain/google-genai/dist/chat_models.cjs:688:32\n    at async RetryOperation._fn (/Users/ezyang/Dev/LibreChat/node_modules/p-retry/index.js:50:12)","status":400,"statusText":"Bad Request"}
{"attemptNumber":1,"level":"error","message":"[api/server/controllers/agents/client.js #sendCompletion] Unhandled error type [GoogleGenerativeAI Error]: Error fetching from https://generativelanguage.googleapis.com/v1beta/models/gemini-2.5-pro-preview-03-25:streamGenerateContent?alt=sse: [400 Bad Request] * GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[content].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[commit_hash].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[subject_line].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[user_prompt].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[old_string].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[include].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[chat_id].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[mode].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[pattern].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[path].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[description].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[reuse_head_chat_id].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[command].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[thought].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[new_string].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[offset].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[arguments].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[new_str].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[limit].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[old_str].type: must be specified when not using one_of, any_of or all_of fields\n","pregelTaskId":"5ad96b5a-f7e2-5d62-a21a-99a8426fc4fb","retriesLeft":2,"stack":"Error: [GoogleGenerativeAI Error]: Error fetching from https://generativelanguage.googleapis.com/v1beta/models/gemini-2.5-pro-preview-03-25:streamGenerateContent?alt=sse: [400 Bad Request] * GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[content].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[commit_hash].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[subject_line].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[user_prompt].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[old_string].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[include].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[chat_id].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[mode].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[pattern].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[path].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[description].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[reuse_head_chat_id].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[command].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[thought].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[new_string].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[offset].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[arguments].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[new_str].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[limit].type: must be specified when not using one_of, any_of or all_of fields\n* GenerateContentRequest.tools[0].function_declarations[0].parameters.properties[old_str].type: must be specified when not using one_of, any_of or all_of fields\n\n    at handleResponseNotOk (/Users/ezyang/Dev/LibreChat/node_modules/@google/generative-ai/dist/index.js:434:11)\n    at process.processTicksAndRejections (node:internal/process/task_queues:105:5)\n    at async makeRequest (/Users/ezyang/Dev/LibreChat/node_modules/@google/generative-ai/dist/index.js:403:9)\n    at async generateContentStream (/Users/ezyang/Dev/LibreChat/node_modules/@google/generative-ai/dist/index.js:862:22)\n    at async /Users/ezyang/Dev/LibreChat/node_modules/@langchain/google-genai/dist/chat_models.cjs:688:32\n    at async RetryOperation._fn (/Users/ezyang/Dev/LibreChat/node_modules/p-retry/index.js:50:12)","status":400,"statusText":"Bad Request"}

Screenshots

Code of Conduct

• I agree to follow this project's Code of Conduct

[ezyang]

The codemcp server is not buggy; it works correctly with 3.7 endpoint. I am also able to use it with gemini-2.5-pro with Goose, so I am fairly confident it is a LibreChat MCP handling problem.

[danny-avila]

It’s more of a Gemini/Google problem. Our only option would be to drop those fields or transform them some other schema. Anthropic and OpenAI both support anyof/oneOf as is, see:

#6773 (reply in thread)

[danny-avila]

Pushing something soon to drop anyOf/oneOf for Gemini models

[danny-avila]

Resolving here: #7040