API Integration Specialist

What it does

API Integration Specialist is a Cursor agent playbook named api-engineer. AgenticKit installs it so a session can adopt this role instead of acting as a generic coding assistant.

The api-engineer agent crafts robust API routes with strict input validation, consistent JSON error responses, standard HTTP status codes, and rate limiting. It turns third-party documentation into working SDKs and webhook handlers.

Builds bulletproof REST/GraphQL endpoints with Zod validation and types. API engineer for Cursor that builds type-safe endpoints, validates request payloads with Zod, and integrates external SaaS webhooks and protocols.

Why it exists

A pile of agent files is not a team. api-engineer exists so one job, api integration specialist, has a written brief, required skills, and a stop condition.

It ships in the Engineering Kit. Skills it must read: REST & API Route Design Patterns; Resilient Error Handling & Fault Tolerance; OAuth 2.0 & Third-Party API Integrations; Strict TypeScript Standards & Type Safety. Commands that adopt this role: /build-api: API Endpoint & Route Generator; /stripe-billing: Stripe Billing & Subscription Setup; /auth-system: Authentication & Role-Based Access System.

When to use it

• Creating new public or internal REST route handlers
• Integrating third-party APIs and verifying incoming webhooks
• Implementing API rate limiting and token bucket throttling

When not to use it

• Do not ask api-engineer to do a different role's job. If you need a launch post, switch agents.
• Do not keep the same chat after this agent has finished its artifact. Start a reviewer in a new thread.
• Do not invoke every agent in the kit for a small change.

Example workflow

1. Install the Engineering Kit so .cursor/agents/api-engineer is on disk.
2. Run /build-api: API Endpoint & Route Generator, or start a chat and tell Cursor to adopt the api-engineer role.
3. The agent should read: REST & API Route Design Patterns; Resilient Error Handling & Fault Tolerance; OAuth 2.0 & Third-Party API Integrations; Strict TypeScript Standards & Type Safety.
4. It produces the artifact for this role only, then stops.
5. A different agent or you review. Same-chat self-review is not a review.

Example usage

Example: "You are api-engineer. Creating new public or internal REST route handlers. Read api-patterns before you edit."

Or let the pipeline invoke it: /build-api: API Endpoint & Route Generator.

Capabilities you should actually see: Type-safe API endpoints with Next.js App Router or Express

Example output

• api-engineer should leave files or a written verdict, not a vibe check. Type-safe API endpoints with Next.js App Router or Express Zod schema validation for request bodies, query params, and headers
• Engineering agents should touch the slice they were given (schema, route, test, or review note) and nothing else.

Best practices

• Type-safe API endpoints with Next.js App Router or Express
• Zod schema validation for request bodies, query params, and headers
• Webhook signature verification (Stripe, GitHub, Resend)
• Standardized error response formats with machine-readable codes
• One role per chat unless a command is explicitly orchestrating a sequence.

Common mistakes

• Using api-engineer as a synonym for 'the Cursor agent'. It is a brief, not the product.
• Skipping the required skills and hoping the role name is enough.
• Letting the writer approve its own PR.
• Invoking this agent and three unrelated ones in the same prompt.