Agent skill

Designing APIs

by CloudAI-X in CloudAI-X/claude-workflow-v2

Designs REST and GraphQL APIs including endpoints, error handling, versioning, and documentation.

Install Designing APIs

skills CLI

$ npx skills add CloudAI-X/claude-workflow-v2 --skill designing-apis -a claude-code

Project install by default; add -g for ~/.claude/skills/.

GitHub CLI

$ gh skill install CloudAI-X/claude-workflow-v2 designing-apis --agent claude-code

Project scope by default; add --scope user for a personal install. Needs GitHub CLI 2.90.0 or later (public preview).

Manual copy

$ git clone --depth 1 https://github.com/CloudAI-X/claude-workflow-v2.git skills-src && mkdir -p .claude/skills && cp -r skills-src/skills/designing-apis .claude/skills/designing-apis && rm -rf skills-src

Use ~/.claude/skills/ instead of .claude/skills for a personal install. The folder must contain SKILL.md.

Claude Code skills documentation · loads skills from .claude/skills/

Paste into Claude Code

Install the "designing-apis" agent skill from https://github.com/CloudAI-X/claude-workflow-v2/tree/main/skills/designing-apis into .claude/skills/designing-apis/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "designing-apis", then confirm the skill loads.

Claude Code copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.

$skill-installer

$skill-installer install https://github.com/CloudAI-X/claude-workflow-v2/tree/main/skills/designing-apis

Type this inside Codex. $skill-installer <name> installs a curated skill from openai/skills. The installer writes to $CODEX_HOME/skills (default ~/.codex/skills). Restart Codex if the skill does not show up.

skills CLI

$ npx skills add CloudAI-X/claude-workflow-v2 --skill designing-apis -a codex

Project install goes to .agents/skills/; add -g for ~/.codex/skills/.

GitHub CLI

$ gh skill install CloudAI-X/claude-workflow-v2 designing-apis --agent codex

Project scope by default (.agents/skills/); add --scope user for a personal install.

Manual copy

$ git clone --depth 1 https://github.com/CloudAI-X/claude-workflow-v2.git skills-src && mkdir -p .agents/skills && cp -r skills-src/skills/designing-apis .agents/skills/designing-apis && rm -rf skills-src

Use ~/.agents/skills/ instead of .agents/skills for a personal install.

Codex skills documentation · loads skills from .agents/skills/

Paste into Codex

Install the "designing-apis" agent skill from https://github.com/CloudAI-X/claude-workflow-v2/tree/main/skills/designing-apis into .agents/skills/designing-apis/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "designing-apis", then confirm the skill loads.

Codex copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.

skills CLI

$ npx skills add CloudAI-X/claude-workflow-v2 --skill designing-apis -a cursor

Project install goes to .agents/skills/; add -g for ~/.cursor/skills/.

GitHub CLI

$ gh skill install CloudAI-X/claude-workflow-v2 designing-apis --agent cursor

Project scope by default (.agents/skills/); add --scope user for a personal install.

Manual copy

$ git clone --depth 1 https://github.com/CloudAI-X/claude-workflow-v2.git skills-src && mkdir -p .cursor/skills && cp -r skills-src/skills/designing-apis .cursor/skills/designing-apis && rm -rf skills-src

Use ~/.cursor/skills/ instead of .cursor/skills for a personal install.

Cursor skills documentation · loads skills from .cursor/skills/, .agents/skills/, .claude/skills/, .codex/skills/

Paste into Cursor

Install the "designing-apis" agent skill from https://github.com/CloudAI-X/claude-workflow-v2/tree/main/skills/designing-apis into .cursor/skills/designing-apis/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "designing-apis", then confirm the skill loads.

Cursor copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.

gemini skills install

$ gemini skills install https://github.com/CloudAI-X/claude-workflow-v2.git --path skills/designing-apis

--scope user (default) or --scope workspace; --path is the subfolder of the repo that holds the skill; --consent skips the security confirmation prompt.

skills CLI

$ npx skills add CloudAI-X/claude-workflow-v2 --skill designing-apis -a gemini-cli

Project install goes to .agents/skills/; add -g for ~/.gemini/skills/.

GitHub CLI

$ gh skill install CloudAI-X/claude-workflow-v2 designing-apis --agent gemini-cli

Project scope by default (.agents/skills/); add --scope user for a personal install.

Manual copy

$ git clone --depth 1 https://github.com/CloudAI-X/claude-workflow-v2.git skills-src && mkdir -p .gemini/skills && cp -r skills-src/skills/designing-apis .gemini/skills/designing-apis && rm -rf skills-src

Use ~/.gemini/skills/ instead of .gemini/skills for a personal install, then run /skills reload.

Gemini CLI skills documentation · loads skills from .gemini/skills/, .agents/skills/

Paste into Gemini CLI

Install the "designing-apis" agent skill from https://github.com/CloudAI-X/claude-workflow-v2/tree/main/skills/designing-apis into .gemini/skills/designing-apis/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "designing-apis", then confirm the skill loads.

Gemini CLI copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.

GitHub CLI

$ gh skill install CloudAI-X/claude-workflow-v2 designing-apis

Installs for Copilot at project scope by default; add --scope user for a personal install. Preview a skill first with gh skill preview. Needs GitHub CLI 2.90.0 or later (public preview).

skills CLI

$ npx skills add CloudAI-X/claude-workflow-v2 --skill designing-apis -a github-copilot

Project install goes to .agents/skills/; add -g for ~/.copilot/skills/.

Manual copy

$ git clone --depth 1 https://github.com/CloudAI-X/claude-workflow-v2.git skills-src && mkdir -p .github/skills && cp -r skills-src/skills/designing-apis .github/skills/designing-apis && rm -rf skills-src

Use ~/.copilot/skills/ instead of .github/skills for a personal install. Commit .github/skills so cloud agent and code review can use it.

GitHub Copilot skills documentation · loads skills from .github/skills/, .claude/skills/, .agents/skills/

Paste into GitHub Copilot

Install the "designing-apis" agent skill from https://github.com/CloudAI-X/claude-workflow-v2/tree/main/skills/designing-apis into .github/skills/designing-apis/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "designing-apis", then confirm the skill loads.

GitHub Copilot copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.

skills CLI

$ npx skills add CloudAI-X/claude-workflow-v2 --skill designing-apis -a opencode

OpenCode documents no install command of its own. Project install goes to .agents/skills/; add -g for ~/.config/opencode/skills/.

GitHub CLI

$ gh skill install CloudAI-X/claude-workflow-v2 designing-apis --agent opencode

Project scope by default (.agents/skills/); add --scope user for a personal install.

Manual copy

$ git clone --depth 1 https://github.com/CloudAI-X/claude-workflow-v2.git skills-src && mkdir -p .opencode/skills && cp -r skills-src/skills/designing-apis .opencode/skills/designing-apis && rm -rf skills-src

Use ~/.config/opencode/skills/ instead of .opencode/skills for a personal install.

OpenCode skills documentation · loads skills from .opencode/skills/, .claude/skills/, .agents/skills/

Paste into OpenCode

Install the "designing-apis" agent skill from https://github.com/CloudAI-X/claude-workflow-v2/tree/main/skills/designing-apis into .opencode/skills/designing-apis/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "designing-apis", then confirm the skill loads.

OpenCode copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.

Facts

Skill name: designing-apis
GitHub stars: 1.4k
Used in: 1 other repo
Token cost: ~1.2k tokens
SKILL.md length: 194 words
Files: 2
Skills in repo: 13
Repo updated: Oct 6, 2026
First seen: Oct 7, 2026
Licence: MIT

At a glance

Designs REST and GraphQL APIs including endpoints, error handling, versioning, and documentation.

Creating new APIs
SKILL.md covers API Design Workflow, REST API Design, API Versioning and Authentication Patterns, plus 5 more sections
Instructions only: no scripts, shell commands, URLs or credentials in SKILL.md
Designing endpoints

What it does

Designing APIs is an agent skill from CloudAI-X/claude-workflow-v2. Designs REST and GraphQL APIs including endpoints, error handling, versioning, and documentation. Use when creating new APIs, designing endpoints, reviewing API contracts, or when asked about REST, GraphQL, or API patterns.

Its SKILL.md is about 1.2k tokens, which your agent loads only when the skill is triggered. The skill folder holds 1 other file (for example `OPENAPI-TEMPLATE.md`).

It sits in Backend & APIs, covering GraphQL and API design. It works with GraphQL and OpenAPI. The repository describes itself as: Universal Claude Code workflow plugin with agents, skills, hooks, and commands. The licence is MIT.

When your agent uses it

Creating new APIs
Designing endpoints
Reviewing API contracts
Asked about REST

Example prompts

“Use the designing-apis skill to design REST and GraphQL APIs including endpoints, error handling, versioning, and documentation”
“/designing-apis”

What it can do on your machine

Read from SKILL.md and the folder at commit 3b5a89e. It shows what the files ask for, not the result of running them.

Tool permissions
Pre-approves nothing: there is no allowed-tools line, so your agent's usual permission prompts apply.
From allowed-tools in the SKILL.md frontmatter.
Runs code
No scripts in the folder and no shell commands in SKILL.md (its code samples are json and graphql).
From the folder's file list and the shell code blocks in SKILL.md.
Network
No URLs in SKILL.md.
From URLs in SKILL.md, links to its own repository left out.
Credentials
Names no API keys, tokens, secrets or passwords.
From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.

Context cost

Designing APIs loads about 1.2k tokens when it runs. Until then it costs about 60 tokens; SKILL.md has 194 words of instructions outside code blocks.

Always · name and description, kept in context so the agent knows when to use it: ~60
When it runs · the whole SKILL.md, loaded when a task matches: ~1.2k

Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.

Safety

Auto-check passed

The automated check found no risky patterns in SKILL.md.

Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); files beside SKILL.md are not scanned.

SKILL.md

The full file from CloudAI-X/claude-workflow-v2 at commit 3b5a89e, republished under its MIT licence (© CloudAI-X). 194 words, ~1,249 tokens.

Download SKILL.mdSave it as .claude/skills/designing-apis/SKILL.md (or your agent's skills folder). This skill also uses 1 other file; get the full folder from GitHub.

name: designing-apis
description: Designs REST and GraphQL APIs including endpoints, error handling, versioning, and documentation. Use when creating new APIs, designing endpoints, reviewing API contracts, or when asked about REST, GraphQL, or API patterns.

Designing APIs

When to Load

Trigger: Designing REST or GraphQL endpoints, API contracts, versioning, request/response formats
Skip: Internal-only code with no API surface

API Design Workflow

Copy this checklist and track progress:

API Design Progress:
- [ ] Step 1: Define resources and relationships
- [ ] Step 2: Design endpoint structure
- [ ] Step 3: Define request/response formats
- [ ] Step 4: Plan error handling
- [ ] Step 5: Add authentication/authorization
- [ ] Step 6: Document with OpenAPI spec
- [ ] Step 7: Validate design against checklist

REST API Design

URL Structure

# Resource-based URLs (nouns, not verbs)
GET    /users              # List users
GET    /users/:id          # Get user
POST   /users              # Create user
PUT    /users/:id          # Replace user
PATCH  /users/:id          # Update user
DELETE /users/:id          # Delete user

# Nested resources
GET    /users/:id/orders   # User's orders
POST   /users/:id/orders   # Create order for user

# Query parameters for filtering/pagination
GET    /users?role=admin&status=active
GET    /users?page=2&limit=20&sort=-createdAt

HTTP Status Codes

Code	Meaning	Use Case
200	OK	Successful GET, PUT, PATCH
201	Created	Successful POST
204	No Content	Successful DELETE
400	Bad Request	Invalid input
401	Unauthorized	Missing/invalid auth
403	Forbidden	Valid auth, no permission
404	Not Found	Resource doesn't exist
409	Conflict	Duplicate, state conflict
422	Unprocessable	Validation failed
429	Too Many Requests	Rate limited
500	Internal Error	Server error

Response Formats

Success Response:

json

{
  "data": {
    "id": "123",
    "type": "user",
    "attributes": {
      "name": "John Doe",
      "email": "john@example.com"
    }
  },
  "meta": {
    "requestId": "abc-123"
  }
}

List Response with Pagination:

json

{
  "data": [...],
  "meta": {
    "total": 100,
    "page": 1,
    "limit": 20,
    "totalPages": 5
  },
  "links": {
    "self": "/users?page=1",
    "next": "/users?page=2",
    "last": "/users?page=5"
  }
}

Error Response:

json

{
  "error": {
    "code": "VALIDATION_ERROR",
    "message": "Invalid input data",
    "details": [
      {
        "field": "email",
        "message": "Must be a valid email address"
      }
    ]
  },
  "meta": {
    "requestId": "abc-123"
  }
}

API Versioning

URL Versioning (Recommended):

/api/v1/users
/api/v2/users

Header Versioning:

Accept: application/vnd.example.v1+json

Authentication Patterns

JWT Bearer Token:

Authorization: Bearer eyJhbGciOiJIUzI1NiIs...

API Key:

X-API-Key: your-api-key

Rate Limiting Headers

X-RateLimit-Limit: 100
X-RateLimit-Remaining: 95
X-RateLimit-Reset: 1609459200
Retry-After: 60

GraphQL Patterns

Schema Design:

graphql

# Abbreviated: input, connection and error types omitted for brevity
type Query {
  user(id: ID!): User
  users(filter: UserFilter, pagination: Pagination): UserConnection!
}

type Mutation {
  createUser(input: CreateUserInput!): UserPayload!
  updateUser(id: ID!, input: UpdateUserInput!): UserPayload!
}

type User {
  id: ID!
  name: String!
  email: String!
  orders(first: Int, after: String): OrderConnection!
}

input CreateUserInput {
  name: String!
  email: String!
}

type UserPayload {
  user: User
  errors: [Error!]
}

OpenAPI Specification Template

See OPENAPI-TEMPLATE.md for the full OpenAPI 3.0 specification template.

API Design Validation

After completing the design, validate against this checklist:

Validation Checklist:
- [ ] All endpoints use nouns, not verbs
- [ ] HTTP methods match operations correctly
- [ ] Consistent response format across endpoints
- [ ] Error responses include actionable details
- [ ] Pagination implemented for list endpoints
- [ ] Authentication defined for protected endpoints
- [ ] Rate limiting headers documented
- [ ] OpenAPI spec is complete and valid

If validation fails, return to the relevant design step and address the issues.

Security Checklist

HTTPS only
Authentication on all endpoints
Authorization checks
Input validation
Rate limiting
Request size limits
CORS properly configured
No sensitive data in URLs
Audit logging

Files

SKILL.md and 1 other file in skills/designing-apis of CloudAI-X/claude-workflow-v2.

SKILL.md
OPENAPI-TEMPLATE.md

Open the folder on GitHubat commit 3b5a89e

Used in 1 other repository

We found 1 copy of this SKILL.md (exact, near-identical or edited) in other folders, from 1 other GitHub owner. This page covers the copy in CloudAI-X/claude-workflow-v2, which our catalogue first saw on October 7, 2026.

aiskillstore/marketplaceskills/cloudai-x/designing-apis

Compare with similar skills

Designing APIs next to the 5 skills that share the most tags, products or categories with it. Stars are the repository's; “used in” counts other GitHub owners with a copy.

Designing APIs compared with similar skills
Skill	Stars	Used in	Tokens	Auto-check	Licence	Repo updated
Designing APIs this skillCloudAI-X/claude-workflow-v2	1.4k	1 repos	~1.2k	Automated safety check: Pass	MIT	3 days ago
API DesignerJeffallan/claude-skills	12k	1 repos	~2k	Automated safety check: Pass	MIT	6 days ago
API Designyonatangross/orchestkit	290	—	~2.9k	Automated safety check: Pass	MIT	today
API Contract Detectionprime-radiant-inc/greenfield	292	—	~4.2k	Automated safety check: Pass	Apache-2.0	2 mo ago
API Contract Designrsmdt/the-startup	557	—	~1.1k	Automated safety check: Pass	MIT	2 mo ago
API Designericrisco/rsc-harness	174	—	~3.1k	Automated safety check: Pass	MIT	yesterday

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API Designer
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12k GitHub starsUsed in 1 repo~2k tokens
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Questions about Designing APIs

What does Designing APIs do?

Designs REST and GraphQL APIs including endpoints, error handling, versioning, and documentation. Designing APIs is an agent skill from CloudAI-X/claude-workflow-v2. Designs REST and GraphQL APIs including endpoints, error handling, versioning, and documentation.

When should I use Designing APIs?

Designing APIs fits situations like: creating new APIs; designing endpoints; reviewing API contracts; asked about REST.

How do I install Designing APIs in Claude Code?

Run `npx skills add CloudAI-X/claude-workflow-v2 --skill designing-apis -a claude-code`. Or copy the skill folder (skills/designing-apis in CloudAI-X/claude-workflow-v2) into .claude/skills/designing-apis in your project. Claude Code loads it when a task matches its description.

How do I install Designing APIs in Codex?

Run `npx skills add CloudAI-X/claude-workflow-v2 --skill designing-apis -a codex`. Or copy the skill folder (skills/designing-apis in CloudAI-X/claude-workflow-v2) into .agents/skills/designing-apis in your project. Codex loads it when a task matches its description.

Can I use Designing APIs in Cursor, Gemini CLI or GitHub Copilot?

Cursor, Gemini CLI, GitHub Copilot and OpenCode also load SKILL.md folders. With the skills CLI, run `npx skills add CloudAI-X/claude-workflow-v2 --skill designing-apis -a cursor` (or -a gemini-cli, github-copilot or opencode for the others). To copy it by hand, put the folder in .cursor/skills/designing-apis, .gemini/skills/designing-apis, .github/skills/designing-apis and .opencode/skills/designing-apis in your project.

What does Designing APIs need to run?

SKILL.md names no scripts, command-line tools or credentials: Designing APIs is instructions for the agent only.

Does Designing APIs access the network?

SKILL.md contains no URLs. Any network use would come from the scripts or tools the agent runs. This is read from the text; nothing was executed.

Is Designing APIs safe to install?

Our automated static check of SKILL.md found no risky patterns, such as piping downloads into a shell, reading credential files or hidden Unicode. It is not a guarantee. Review the folder before installing.

What licence does Designing APIs use?

Designing APIs is published under the MIT licence (the repository's licence). It allows redistribution, so the full SKILL.md is shown on this page.

How many tokens does Designing APIs use?

About 1.2k tokens (SKILL.md is roughly 5k characters). Agents keep only the skill's name and description in context until a task matches; then they load SKILL.md in full.

What are the alternatives to Designing APIs?

Skills that share tags, products or a category with Designing APIs: API Designer (Jeffallan/claude-skills, 12k stars), API Design (yonatangross/orchestkit, 290 stars), API Contract Detection (prime-radiant-inc/greenfield, 292 stars) and API Contract Design (rsmdt/the-startup, 557 stars). The comparison table on this page puts their stars, adoption, token cost, safety result and licence side by side.

Who maintains Designing APIs?

CloudAI-X (a GitHub user) maintains it in CloudAI-X/claude-workflow-v2, which has 1,418 GitHub stars. The repository holds 13 skills in this directory. The repository was last updated on October 6, 2026.

Source: CloudAI-X/claude-workflow-v2 on GitHub. Facts on this page come from the repository at the commit we read; the author's words are quoted as theirs.

Install Designing APIs

Facts

At a glance

What it does

When your agent uses it

Example prompts

What it can do on your machine

Tool permissions

Runs code

Network

Credentials

Context cost

Safety

SKILL.md

Designing APIs

When to Load

API Design Workflow

REST API Design

URL Structure

HTTP Status Codes

Response Formats

API Versioning

Authentication Patterns

Rate Limiting Headers

GraphQL Patterns

OpenAPI Specification Template

API Design Validation

Security Checklist

Files

Used in 1 other repository

Compare with similar skills

Similar skills

More from CloudAI-X/claude-workflow-v2

Related

Questions about Designing APIs