NestJS¶

Recommended setup (OpenAPI)¶

With @nestjs/swagger configured, NestJS serves a spec (commonly at /api-json) and Postman MCP uses the OpenAPI path:

postman-mcp init
# detects NestJS, finds http://localhost:3000/api-json
# sets inputMode = openapi

This captures your DTOs, decorators, and guards accurately from the generated spec.

Code-parsing fallback¶

Without a spec, the NestJS parser (input/parsers/nestjs.py) extracts:

Aspect	From
Routes	`@Controller` + `@Post()` / `@Get()` decorators
Body and response types	DTO classes with `class-validator` decorators
Headers	`@Headers('x-api-key') key: string` parameters
Auth	`@UseGuards(AuthGuard)`

DTO class bodies are read with a brace-depth walker rather than a regex that stops at the first }, so a property decorated with an object-literal argument (for example @ApiProperty({ type: String }) from @nestjs/swagger) doesn't truncate the class or leak type/example in as bogus fields.

Heuristic TypeScript parsing

There's no Python TypeScript AST, so this path uses regex and heuristics, not a real parser. Decorators spread across files and dynamic module wiring may be missed. Prefer the OpenAPI path (@nestjs/swagger) when you can; affected routes are labeled [code] in the diff so you can spot them.

Example¶

See examples/nestjs-api/, which has the real generated Collection items checked in under expected-output/.