API Endpoint & Route Generator

What it does

/build-api is a Cursor slash command. Type it in chat to run a saved workflow: API Endpoint & Route Generator.

Generates robust backend API routes with strict request payload validation, database transactions, standardized JSON error envelopes, and rate limiting.

Type-safe REST/GraphQL routes with Zod schema validation and error envelopes. Unlike a skill, a command is something you invoke on purpose. The agent does not decide to run /build-api for you.

Why it exists

Founders retype the same multi-step prompt until it rots. /build-api exists so the pipeline, all 4 steps of it, is a file in .cursor/commands, versioned with the repo.

It ships in the Engineering Kit. It is wired to API Integration Specialist (api-engineer), Senior Backend Architect (backend-architect), and App Security Auditor (security-auditor). Required skills: REST & API Route Design Patterns; Resilient Error Handling & Fault Tolerance; Authentication & Session Security Patterns.

When to use it

• Use when creating new backend endpoints, controller handlers, or webhook receivers.
• Use /build-api when you want that pipeline, not a freeform chat. If you only need one step, use a narrower command or a single agent.
• Start a new chat. Do not run this command in a thread that just wrote marketing copy.

When not to use it

• Do not run /build-api as a substitute for reading the diff. The command produces files; you still gate them.
• Do not chain it into a 40-turn chat. Fresh context is part of the design.
• Do not run it if you have not filled CURSOR.md. The pipeline will invent a stack.

Example workflow

1. Define request and response TypeScript interfaces and Zod validation schemas
2. Implement route handler with auth session verification and workspace permission check
3. Execute database transactions using Drizzle ORM / Prisma
4. Return standardized HTTP responses with appropriate status codes and error handles

Example usage

Type this in Cursor chat: /build-api POST /api/v1/teams with member invite validation and email dispatch

The command file tells the session which agents to adopt and which skills to read. You should see phase headers, not a single dump of code.

If a phase fails its gate, stop. Do not add 'just continue'.

Example output

• Expected artifact: src/app/api/.../route.ts
• Expected artifact: src/lib/validations/...
• Expected artifact: src/types/...

Best practices

• Keep the prompt specific. /build-api POST /api/v1/teams with member invite validation and email dispatch is the shape: object, constraint, and outcome.
• Let the listed agents work in order: api-engineer → backend-architect → security-auditor.
• Save outputs in the repo. Chat-only answers evaporate.
• Engineering commands should leave tests or an audit note, not only implementation files.

Common mistakes

• Typing /build-api with no object ('do the thing'). The pipeline will guess.
• Re-running the command in the same chat after a failed gate instead of fixing the failing file.
• Editing the command file to skip review so it 'goes faster'.
• Skipping the REST & API Route Design Patterns skill that the command depends on.