API Development MCP Servers

Try 26 utility REST APIs keylessly: NAICS classification, IP geo, email validation, currency.

Strips an API response down to what was actually asked for: drops the envelope, unwraps the data key, flattens the nesting into dotted paths, and pulls out named fields..

Public HTAG discovery for MCP tools, API endpoints, OpenAPI ops, and agents.

Apideck Unified API MCP — 229 tools across 200+ SaaS connectors (accounting, HRIS, file storage).

Swagger Petstore API (v1.0.27) as MCP for testing and prototyping powered by the HAPI MCP server

Aggregated live-data gateway exposing 5,000+ tools across 1,300+ verified public sources (business registries, government, market, news

Convert REST API specifications (OpenAPI 3.x, Swagger 2.x, OpenAPI Actions) into MCP tools for AI agents. Supports JSON and YAML formats.