nk3750/jitapi

**Point Claude at any API. JitAPI figures out which endpoints to call and in what order — automatically.**
JitAPI is an MCP server that lets Claude interact with *any* API from its OpenAPI spec. Instead of dumping hundreds of endpoints into context, JitAPI uses semantic search and a dependency graph to surface only what's needed — then Claude plans and executes the calls.
https://github.com/user-attachments/assets/53f72f89-a41a-4a9c-a688-ec876ea05fbd
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The Problem
Stripe has 300+ endpoints. GitHub has 800+. Loading the full spec into Claude's context wastes tokens and causes hallucinations. Writing a custom MCP server for every API you use doesn't scale.
**JitAPI solves this:** register any OpenAPI spec once, then ask for what you need in plain English. It finds the right endpoints, resolves dependencies between them, and lets Claude execute the calls.
Quick Start
Add to your Claude Code config (.mcp.json):
That's it. No API keys required — JitAPI uses local embeddings out of the box.
Then in Claude:
Multi-API Orchestration
The killer feature: register multiple APIs and ask questions that span them. JitAPI searches across all registered APIs and Claude chains the calls.
How It Works
1. **Register** — Parse an OpenAPI spec, build a dependency graph (which endpoints need data from which other endpoints), and create searchable embeddings for all endpoints
2. **Search** — When you ask a question, JitAPI embeds your query and finds the most relevant endpoints via cosine similarity
3. **Expand** — The dependency graph adds any prerequisite endpoints (e.g., "you need to call GET /users first to get the user_id for POST /orders")
4. **Execute** — Claude gets the endpoint schemas and makes the API calls, passing data between steps
MCP Tools
| Tool | Description |
|------|-------------|
| register_api | Register an API from an OpenAPI spec URL |
| list_apis | List all registered APIs and their endpoint counts |
| search_endpoints | Semantic search across endpoints using natural language |
| get_workflow | Find relevant endpoints with dependency resolution and full schemas |
| get_endpoint_schema | Get the complete schema for a specific endpoint |
| call_api | Execute a single API call with auth, path params, query params, and body |
| set_api_auth | Configure authentication (API key header, API key query param, or bearer token) |
| delete_api | Remove a registered API and all its data |
Setup
Claude Code
Create .mcp.json in your project directory (or ~/.claude.json for global access):
Claude Desktop
Add to your Claude Desktop config:
| OS | Config path |
|----|-------------|
| macOS | ~/Library/Application Support/Claude/claude_desktop_config.json |
| Windows | %APPDATA%\Claude\claude_desktop_config.json |
| Linux | ~/.config/Claude/claude_desktop_config.json |
Embedding Providers
JitAPI works out of the box with **local embeddings** (fastembed) — no API keys needed. For better search quality on large APIs, you can add a cloud embedding provider:
| Provider | Quality | Setup |