API and Interface Design

SkillMonitoring & ops

Designs or reviews HTTP, REST, GraphQL, RPC, CLI, webhook, event, and service interfaces with explicit inputs, outputs, errors, compatibility, idempotency, pagination, authentication, versioning, and observability. Use when introducing or changing an API or cross-component contract. Not for internal implementation details with no boundary or for debugging one API failure; use root-cause-debugging there.

Available today. Use it from your connected AI after setup.

Connect ahel once, and every AI you use reads what you have installed.

Then ask your AI: use the API and Interface Design skill

What this skill tells your AI

The instructions your AI receives, as published by thiientv/godmode in skills/api-and-interface-design/SKILL.md and read by ahel’s review.

Design the contract from the caller's failure modes, not only the happy path.

Establish the contract

  1. Identify consumers, trust boundaries, lifecycle, latency expectations, and ownership.
  2. Define request/command shape, response/event shape, status or error model, validation, defaults, and canonical examples.
  3. Decide idempotency, retries, ordering, pagination, concurrency, rate limits, cancellation, and partial failure behavior.
  4. Define authentication, authorization, sensitive fields, and audit needs.
  5. Decide compatibility and versioning: additive change, migration, deprecation, or explicit breaking release.

Read contract-checklist.md for the review matrix. Keep the contract close to the owning schema or source of truth and generate clients/docs only when the repository already supports generation.

Implementation handoff

Write examples that can become contract tests. Include malformed input, missing resource, duplicate request, timeout, dependency failure, permission denial, and oversized input cases. Make error codes stable enough for callers and messages safe enough for logs and users.

Do not expose internal stack traces, persistence identifiers, or implementation details by accident. Do not add versioning machinery before a compatibility need exists.

Completion condition

Consumers can predict valid requests, successful and failed responses, retry behavior, compatibility impact, and the evidence that proves the boundary.

Signals

GitHub stars
94
Forks
77
Last commit
Aug 2026
Advanced
Catalog kind
skill
Gateway key
api-and-interface-design-thiientv
Source
github.com/thiientv/godmode