About onomeo
onomeo is an MCP server for coding agents that need a second opinion from models available through the onomeo API. It can query one model or compare several responses side by side.
Key features
- 01List currently available models
- 02Ask a selected or automatic model
- 03Compare 2–4 model responses
Use cases
- 01Get another review of a code diff
- 02Compare answers to a regex question
- 03Check which free models are available
MCP support
Exposes tools to list models, send prompts to a model, and compare responses from multiple models to MCP clients.
Configuration
Local server config is the same for every client. Copy it into your client’s MCP config file.
We haven’t collected a package or remote endpoint for this server. Follow the instructions in the project README.
Tools
Local servers expose tools only once running on your machine, and the maintainer has not provided a tool list.
Details
From the project READMEonomeo-mcp
An MCP server that lets your coding agent ask other LLMs for a second opinion. It talks to onomeo, an OpenAI-compatible API where a rotating set of models (DeepSeek, GLM, Gemini, Mistral and others) is free to call with no credit card.
Typical uses from Claude Code, Cursor, Cline or any other MCP client:
- "Ask DeepSeek to review this diff and tell me what it would change."
- "Send this regex question to three models and compare the answers."
- "Which free models are up right now?"
onomeo is in public beta. Not every feature is guaranteed to work, and feedback is actively collected and very welcome: open an issue here or write to [email protected]. This server is written and maintained by the operator of onomeo.
Tools
| Tool | What it does |
|---|---|
list_models | Lists the models served right now, split into free and pay-as-you-go, with the current free call limit. Needs no API key. |
ask_model | Sends a prompt to one model and returns the answer. model defaults to auto, which picks a healthy free model and reports which one answered. |
compare_models | Sends the same prompt to 2-4 models in parallel and returns the answers side by side. |
Setup
- Sign up at onomeo.com and create an API key. No card is required for the free models.
- Add the server to your client. Node.js 20 or newer is required.
Claude Code:
claude mcp add onomeo -e ONOMEO_API_KEY=your-key -- npx -y github:Owaid0723666/onomeo-mcp
Cursor, Claude Desktop, Cline, Windsurf and other clients that read an mcpServers block:
{
"mcpServers": {
"onomeo": {
"command": "npx",
"args": ["-y", "github:Owaid0723666/onomeo-mcp"],
"env": { "ONOMEO_API_KEY": "your-key" }
}
}
}
Claude Desktop: download onomeo-mcp.mcpb from the latest release, open it, and paste your key when asked.
Limits and pricing
Checked on 2026-10-10; list_models always returns the live values.
- Free models: 30 calls per 5 hours per account, refilled automatically. One call covers up to 50,000 characters.
- Paid models (Claude, GPT, Grok, Gemini Pro and others): pay-as-you-go from a 5 USD top-up, no subscription.
compare_modelsuses one call per model.
Privacy
Free models are served through third-party free tiers, and several of them may use prompts for training. Each model page on onomeo states what is known. Do not send secrets or private code to free models.
Development
npm install
npm test # against a local stub
ONOMEO_LIVE=1 ONOMEO_API_KEY=your-key npm test # one real call to "auto"
ONOMEO_BASE_URL overrides the API host.
License
MIT
Comments
New to MCP?
From what the protocol is to installing your first server, these answers cover most first questions.
An open protocol that defines how AI applications connect to external tools and data in a uniform way. Clients talk to the model; MCP servers provide tools, resources and prompt templates. They exchange standard messages, so one server can be reused by many clients.