MCPSERV.CLUB
kadykov

MCP OpenAPI Schema Explorer

MCP Server

Token‑efficient access to OpenAPI specs via MCP Resources

Active(93)
53stars
0views
Updated 12 days ago

About

A lightweight MCP server that loads and serves large OpenAPI v3.0 or Swagger v2.0 specifications as read‑only resources, allowing LLM clients to explore API structures without loading the entire spec into context.

Capabilities

Resources
Access data sources
Tools
Execute functions
Prompts
Pre-built templates
Sampling
AI model interactions

MCP OpenAPI Schema Explorer Logo

Overview

The OpenAPI Schema Explorer MCP server solves a common bottleneck for developers who want to interrogate large OpenAPI or Swagger specifications without exhausting an LLM’s context window. By exposing the specification as MCP Resources, it allows AI assistants—such as Claude Desktop or Cline—to fetch and traverse specific sections of the schema on demand. This token‑efficient approach means that only the parts of a 50 MB spec needed for a particular query are transmitted, keeping prompt sizes manageable while still giving the assistant full semantic understanding of the API.

At its core, the server loads a specification from either a local file path or an HTTP/HTTPS URL. When a Swagger v2.0 spec is detected, it automatically converts the document to OpenAPI v3.0, ensuring consistent downstream consumption. Once loaded, the spec is broken into logical resource endpoints that mirror the structure of an OpenAPI document: paths, components, schemas, and security definitions. Developers can then reference these resources directly within their MCP client, enabling features like “browse all endpoints of ” or “display the request body schema for .” Because resources are read‑only, there is no risk of accidental modification, and the server can safely expose large datasets without exposing writable APIs.

Key capabilities include:

  • Token‑efficient exploration – only requested fragments are streamed to the LLM, preserving context limits.
  • Automatic Swagger‑to‑OpenAPI conversion – a single entry point for both spec versions.
  • Rich resource hierarchy – nested resources that reflect the natural layout of an OpenAPI document.
  • Remote and local loading – flexible integration with CI/CD pipelines or local development setups.

Typical use cases span a wide range of AI‑augmented workflows. A developer using Claude Desktop can ask the assistant to “list all endpoints that require OAuth2,” and the assistant will fetch just the relevant security definitions. In a documentation‑generation pipeline, an LLM can iterate over all schemas to auto‑generate TypeScript types without pulling the entire spec into memory. QA teams can have an AI agent explore error responses for a specific endpoint, speeding up test case creation. Because the server is an MCP resource provider rather than a tool executor, it fits naturally into any client that supports browsing data sources, making it ideal for knowledge‑base construction and API discovery.

The OpenAPI Schema Explorer stands out by combining the declarative nature of MCP Resources with the practical need for large‑spec handling. Its automatic conversion, lightweight deployment via Docker or npm, and zero‑install approach mean that teams can add rich API introspection to their AI workflows with minimal friction, unlocking deeper automation and faster onboarding for both developers and LLMs alike.