api-tools✓ Pass

SKILL.md Content

---
name: api-tools
description: API testing, documentation, and development tools
domain: tools-integrations
version: 1.0.0
tags: [postman, insomnia, swagger, openapi, curl, httpie]
triggers:
  keywords:
    primary: [postman, insomnia, curl, httpie, swagger, openapi]
    secondary: [api test, request, response, collection, mock server, bruno]
  context_boost: [api, endpoint, http, rest]
  context_penalty: [frontend, ui, design]
  priority: medium
---

# API Tools

## Overview

Tools and techniques for API development, testing, documentation, and debugging.

---

## HTTP Clients

### cURL

```bash
# Basic GET
curl https://api.example.com/users

# GET with headers
curl -H "Authorization: Bearer TOKEN" \
     -H "Accept: application/json" \
     https://api.example.com/users

# POST with JSON body
curl -X POST \
     -H "Content-Type: application/json" \
     -d '{"name": "John", "email": "[email protected]"}' \
     https://api.example.com/users

# POST with form data
curl -X POST \
     -F "[email protected]" \
     -F "name=My Document" \
     https://api.example.com/upload

# PUT request
curl -X PUT \
     -H "Content-Type: application/json" \
     -d '{"name": "Updated Name"}' \
     https://api.example.com/users/123

# DELETE request
curl -X DELETE https://api.example.com/users/123

# Show response headers
curl -i https://api.example.com/users

# Verbose output (debugging)
curl -v https://api.example.com/users

# Follow redirects
curl -L https://example.com/redirect

# Save response to file
curl -o response.json https://api.example.com/users

# With authentication
curl -u username:password https://api.example.com/protected
curl --oauth2-bearer TOKEN https://api.example.com/protected

# Measure timing
curl -w "@curl-format.txt" -o /dev/null -s https://api.example.com
```

```txt
# curl-format.txt
     time_namelookup:  %{time_namelookup}s\n
        time_connect:  %{time_connect}s\n
     time_appconnect:  %{time_appconnect}s\n
    time_pretransfer:  %{time_pretransfer}s\n
       time_redirect:  %{time_redirect}s\n
  time_starttransfer:  %{time_starttransfer}s\n
                     ----------\n
          time_total:  %{time_total}s\n
```

### HTTPie

```bash
# GET request (more readable output)
http https://api.example.com/users

# With headers
http https://api.example.com/users \
  Authorization:"Bearer TOKEN" \
  Accept:application/json

# POST with JSON (default)
http POST https://api.example.com/users \
  name=John \
  [email protected]

# POST with raw JSON
http POST https://api.example.com/users \
  < user.json

# Form data
http -f POST https://api.example.com/login \
  username=john \
  password=secret

# File upload
http -f POST https://api.example.com/upload \
  [email protected]

# Download file
http --download https://api.example.com/files/document.pdf

# Session persistence
http --session=user-session POST https://api.example.com/login
http --session=user-session GET https://api.example.com/profile

# Only headers
http --headers https://api.example.com/users

# Only body
http --body https://api.example.com/users
```

---

## API Testing

### Postman Collections

```json
{
  "info": {
    "name": "User API",
    "schema": "https://schema.getpostman.com/json/collection/v2.1.0/collection.json"
  },
  "variable": [
    {
      "key": "baseUrl",
      "value": "https://api.example.com"
    },
    {
      "key": "token",
      "value": ""
    }
  ],
  "item": [
    {
      "name": "Auth",
      "item": [
        {
          "name": "Login",
          "request": {
            "method": "POST",
            "url": "{{baseUrl}}/auth/login",
            "header": [
              { "key": "Content-Type", "value": "application/json" }
            ],
            "body": {
              "mode": "raw",
              "raw": "{\"email\": \"{{email}}\", \"password\": \"{{password}}\"}"
            }
          },
          "event": [
            {
              "listen": "test",
              "script": {
                "exec": [
                  "pm.test('Status code is 200', function () {",
                  "    pm.response.to.have.status(200);",
                  "});",
                  "",
                  "pm.test('Response has token', function () {",
                  "    var jsonData = pm.response.json();",
                  "    pm.expect(jsonData.token).to.be.a('string');",
                  "    pm.collectionVariables.set('token', jsonData.token);",
                  "});"
                ]
              }
            }
          ]
        }
      ]
    },
    {
      "name": "Users",
      "item": [
        {
          "name": "List Users",
          "request": {
            "method": "GET",
            "url": {
              "raw": "{{baseUrl}}/users?page=1&limit=10",
              "query": [
                { "key": "page", "value": "1" },
                { "key": "limit", "value": "10" }
              ]
            },
            "header": [
              { "key": "Authorization", "value": "Bearer {{token}}" }
            ]
          },
          "event": [
            {
              "listen": "test",
              "script": {
                "exec": [
                  "pm.test('Status code is 200', function () {",
                  "    pm.response.to.have.status(200);",
                  "});",
                  "",
                  "pm.test('Response is an array', function () {",
                  "    var jsonData = pm.response.json();",
                  "    pm.expect(jsonData.data).to.be.an('array');",
                  "});",
                  "",
                  "pm.test('Response time is less than 500ms', function () {",
                  "    pm.expect(pm.response.responseTime).to.be.below(500);",
                  "});"
                ]
              }
            }
          ]
        }
      ]
    }
  ]
}
```

### Newman CLI

```bash
# Run Postman collection
newman run collection.json

# With environment
newman run collection.json -e environment.json

# Generate HTML report
newman run collection.json \
  --reporters cli,html \
  --reporter-html-export report.html

# Run specific folder
newman run collection.json --folder "Users"

# With iteration data
newman run collection.json -d data.json -n 10

# Set environment variables
newman run collection.json \
  --env-var "baseUrl=https://staging.api.example.com" \
  --env-var "token=xxx"
```

---

## OpenAPI / Swagger

### OpenAPI Specification

```yaml
# openapi.yaml
openapi: 3.0.3
info:
  title: User API
  description: API for managing users
  version: 1.0.0
  contact:
    email: [email protected]
  license:
    name: MIT

servers:
  - url: https://api.example.com/v1
    description: Production
  - url: https://staging-api.example.com/v1
    description: Staging

tags:
  - name: Users
    description: User management operations
  - name: Auth
    description: Authentication operations

paths:
  /users:
    get:
      summary: List users
      description: Returns a paginated list of users
      operationId: listUsers
      tags:
        - Users
      security:
        - bearerAuth: []
      parameters:
        - name: page
          in: query
          description: Page number
          schema:
            type: integer
            minimum: 1
            default: 1
        - name: limit
          in: query
          description: Items per page
          schema:
            type: integer
            minimum: 1
            maximum: 100
            default: 20
        - name: search
          in: query
          description: Search term
          schema:
            type: string
      responses:
        '200':
          description: Successful response
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/UserList'
        '401':
          $ref: '#/components/responses/Unauthorized'

    post:
      summary: Create user
      operationId: createUser
      tags:
        - Users
      security:
        - bearerAuth: []
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/CreateUser'
      responses:
        '201':
          description: User created
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/User'
        '400':
          $ref: '#/components/responses/BadRequest'
        '401':
          $ref: '#/components/responses/Unauthorized'

  /users/{id}:
    get:
      summary: Get user by ID
      operationId: getUserById
      tags:
        - Users
      security:
        - bearerAuth: []
      parameters:
        - name: id
          in: path
          required: true
          schema:
            type: string
            format: uuid
      responses:
        '200':
          description: Successful response
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/User'
        '404':
          $ref: '#/components/responses/NotFound'

components:
  schemas:
    User:
      type: object
      required:
        - id
        - email
        - createdAt
      properties:
        id:
          type: string
          format: uuid
          example: "123e4567-e89b-12d3-a456-426614174000"
        email:
          type: string
          format: email
          example: "[email protected]"
        name:
          type: string
          example: "John Doe"
        role:
          type: string
          enum: [user, admin]
          default: user
        createdAt:
          type: string
          format: date-time

    CreateUser:
      type: object
      required:
        - email
        - password
      properties:
        email:
          type: string
          format: email
        password:
          type: string
          minLength: 8
        name:
          type: string

    UserList:
      type: object
      properties:
        data:
          type: array
          items:
            $ref: '#/components/schemas/User'
        meta:
          $ref: '#/components/schemas/PaginationMeta'

    PaginationMeta:
      type: object
      properties:
        page:
          type: integer
        limit:
          type: integer
        total:
          type: integer
        totalPages:
          type: integer

    Error:
      type: object
      properties:
        code:
          type: string
        message:
          type: string

  responses:
    BadRequest:
      description: Bad request
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Error'

    Unauthorized:
      description: Unauthorized
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Error'

    NotFound:
      description: Resource not found
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Error'

  securitySchemes:
    bearerAuth:
      type: http
      scheme: bearer
      bearerFormat: JWT
```

### Generate Client SDK

```bash
# Generate TypeScript client
npx openapi-generator-cli generate \
  -i openapi.yaml \
  -g typescript-fetch \
  -o ./generated/client

# Generate Python client
openapi-generator generate \
  -i openapi.yaml \
  -g python \
  -o ./generated/python-client
```

---

## Mock Servers

### Prism (OpenAPI Mock Server)

```bash
# Start mock server
npx @stoplight/prism-cli mock openapi.yaml

# With dynamic responses
npx @stoplight/prism-cli mock openapi.yaml --dynamic

# Custom port
npx @stoplight/prism-cli mock openapi.yaml -p 4010
```

### JSON Server (Quick REST API)

```json
// db.json
{
  "users": [
    { "id": 1, "name": "John", "email": "[email protected]" },
    { "id": 2, "name": "Jane", "email": "[email protected]" }
  ],
  "posts": [
    { "id": 1, "title": "Hello World", "userId": 1 }
  ]
}
```

```bash
# Start server
npx json-server --watch db.json --port 3001

# Routes automatically created:
# GET    /users
# GET    /users/1
# POST   /users
# PUT    /users/1
# DELETE /users/1
# GET    /posts?userId=1
```

---

## API Debugging

### Request/Response Logging

```typescript
import axios from 'axios';

// Request interceptor
axios.interceptors.request.use((config) => {
  console.log('Request:', {
    method: config.method?.toUpperCase(),
    url: config.url,
    params: config.params,
    data: config.data,
    headers: config.headers,
  });
  return config;
});

// Response interceptor
axios.interceptors.response.use(
  (response) => {
    console.log('Response:', {
      status: response.status,
      headers: response.headers,
      data: response.data,
    });
    return response;
  },
  (error) => {
    console.log('Error:', {
      status: error.response?.status,
      data: error.response?.data,
    });
    return Promise.reject(error);
  }
);
```

---

## Related Skills

- [[api-design]] - API design patterns
- [[testing-strategies]] - API testing
- [[backend]] - Backend development

License

Declared license: MIT

MIT License

Copyright (c) 2025 majiayu000

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.

View the license in the source repository — the version published there is authoritative.