@tyk-technologies/api-to-mcp

Parses OpenAPI 3.0+ specifications and generates TypeScript/JavaScript MCP tool implementations that conform to the Model Context Protocol specification. The generator introspects OpenAPI operation definitions (paths, methods, parameters, request/response schemas) and emits executable MCP tool code with proper schema validation, error handling, and protocol compliance. Uses AST-based code generation to produce idiomatic, type-safe tool wrappers that can be immediately integrated into MCP servers.

Transforms OpenAPI parameter definitions (path, query, header, body) into MCP tool input schemas with proper type inference, validation constraints, and required/optional field marking. Maps OpenAPI JSON Schema constraints (minLength, maxLength, pattern, enum, minimum, maximum) to MCP schema equivalents, ensuring generated tools enforce the same validation rules as the original API specification. Handles complex nested objects and array types through recursive schema traversal.

Generates boilerplate MCP tool implementations that include HTTP client setup, request/response handling, and error transformation logic. The scaffolding creates tool functions that accept MCP input objects, construct HTTP requests using the OpenAPI operation definition, execute calls against a configurable API base URL, and transform HTTP responses back into MCP-compatible output. Includes error handling patterns for HTTP status codes, network failures, and response parsing errors with appropriate MCP error reporting.

Maps individual OpenAPI operations (GET /users/{id}, POST /users, etc.) to discrete MCP tool definitions with appropriate naming, descriptions, and input/output schemas. Extracts operation metadata (summary, description, tags, operationId) from OpenAPI and uses it to generate human-readable MCP tool names and descriptions. Creates separate tool definitions for each operation, allowing LLMs to discover and invoke specific API endpoints as independent tools rather than a monolithic API wrapper.

Generates TypeScript type definitions for all OpenAPI request and response schemas, enabling type-safe tool implementations and IDE autocomplete support. Converts OpenAPI JSON Schema definitions into TypeScript interfaces with proper typing for primitive types, objects, arrays, and union types. Includes support for schema references ($ref) and generates type files that can be imported alongside generated tool code for full type safety during development.