The Complete Production SOP: How to Deploy and Run NestJS Interceptors Request Transformation & Logging in Autonomous AI Agents

Agent runtimes such as Claude Code and Codex parse procedural behaviors from workspace-mounted manifests. By creating a standardized `.agents/skills` directory in your workspace and mounting the `nestjs-interceptors-logging-transform` definition, the AI agent dynamically registers frontmatter triggers (`write nestjs interceptor`, `transform response nestjs interceptor`, `log execution time interceptor`) and enforces strict NestInterceptor interface requirements.

import {
  CallHandler,
  ExecutionContext,
  Injectable,
  NestInterceptor,
} from '@nestjs/common';
import { Observable } from 'rxjs';
import { map } from 'rxjs/operators';

export interface Response<T> {
  data: T;
  statusCode: number;
  timestamp: string;
}

@Injectable()
export class TransformInterceptor<T> implements NestInterceptor<T, Response<T>> {
  intercept(context: ExecutionContext, next: CallHandler): Observable<Response<T>> {
    const ctx = context.switchToHttp();
    const response = ctx.getResponse();
    const statusCode = response.statusCode;

    return next.handle().pipe(
      map((data) => ({
        data,
        statusCode,
        timestamp: new Date().toISOString(),
      })),
    );
  }
}

Verify that your runtime environment has the required RxJS operators and NestJS core packages installed. For interceptors handling structured log shipping or caching, ensure destination URLs or Redis credentials are configuration-driven via `ConfigService` rather than hardcoded.

When invoking Codex, Claude Code, or Cursor, use triggering terms matching the skill's declared triggers: 'write nestjs interceptor', 'transform response nestjs interceptor', or 'log execution time interceptor'. This instructs the agent to read the SOP rules and generate standard RxJS piping instead of procedural Express middleware.

Run TypeScript compilation and unit tests on the generated interceptor. The skill enforces that the agent validates its own changes against existing controller specs to ensure response shapes match expected contracts.