swagger-testcase-mcp

MCP server for API testing: generates test cases, validates specs, compares versions, and creates mock data from Swagger/OpenAPI specifications.

Feed it your API spec URL — get structured, categorized test cases (positive, negative, boundary, auth, security, idempotency, pagination) ready for manual testing or import into your TMS.

Why

• Writing test cases manually is slow. A single endpoint with 10+ parameters can require 30-50 test cases across positive, negative, boundary, and security scenarios. Multiply that by dozens of endpoints — and you're spending days on routine work instead of actual testing.
• Negative and boundary cases get skipped. Under deadline pressure, QA focuses on happy paths. Edge cases, invalid inputs, and security checks are the first to be cut — and the first to cause production incidents.
• Specs change faster than test docs, and internal APIs get left behind. New endpoints, renamed fields, changed constraints — keeping test cases in sync is constant overhead. Corporate APIs behind VPN or custom auth make it even harder, since most tooling doesn't support authenticated spec access.
• Getting test cases into your TMS takes extra steps. Even if you write great test cases, formatting them for TestRail, Allure, or Postman import is tedious work that adds no value.

This tool automates the baseline: point it at any Swagger/OpenAPI spec (public, internal, localhost), get categorized test cases in seconds, and save ready-to-import files for your TMS or test runner. You focus on business logic and exploratory testing — the tool handles the rest.

Features

• Parses Swagger 2.0 and OpenAPI 3.x — JSON and YAML
• Smart test case generation — analyzes parameters, schemas, constraints, response codes, and security to produce relevant test cases
• 8 test categories — positive, negative, boundary, authorization, business logic, security injection, idempotency, pagination & sorting
• 9 export formats — Markdown, JSON, CSV, Allure CSV, Gherkin, Postman, k6, pytest, TestRail CSV (two templates: Steps and Text)
• Spec validation — quality scoring with 11 rules and actionable suggestions
• Spec comparison — diff two versions with breaking change detection
• Mock data generation — realistic test data from schemas with locale support
• Coverage analysis — identify gaps in test coverage with prioritized recommendations
• Auto-save to file — exports are saved to the working directory automatically, no manual copy-paste
• Configurable generation — filter by category, priority, locale, custom preconditions
• Batch generation — filter by tag, HTTP method, path prefix, deprecated status
• Works with any MCP client — Claude Desktop, Cursor, VS Code + Cline, etc.

Generated test case categories

Installation

npm install -g swagger-testcase-mcp

Or run directly with npx:

npx swagger-testcase-mcp

Configuration

{
  "mcpServers": {
    "swagger-testcase-mcp": {
      "command": "npx",
      "args": ["-y", "swagger-testcase-mcp"]
    }
  }
}

{
  "mcpServers": {
    "swagger-testcase-mcp": {
      "command": "npx",
      "args": ["-y", "swagger-testcase-mcp"]
    }
  }
}

{
  "servers": {
    "swagger-testcase-mcp": {
      "command": "npx",
      "args": ["-y", "swagger-testcase-mcp"]
    }
  }
}

{
  "swagger-testcase-mcp": {
    "command": "npx",
    "args": ["-y", "swagger-testcase-mcp"]
  }
}

{
  "servers": {
    "swagger-testcase-mcp": {
      "command": "npx",
      "args": ["-y", "swagger-testcase-mcp"]
    }
  }
}

{
  "mcpServers": {
    "swagger-testcase-mcp": {
      "command": "npx",
      "args": ["-y", "swagger-testcase-mcp"]
    }
  }
}

Quick Start

1. "Load the spec from https://petstore3.swagger.io/api/v3/openapi.json"
2. "Generate test cases for POST /pet"
3. "Export as Postman collection"

Here is what the generated output looks like (markdown export):

## Positive Tests (1)

### TC-001: POST /pet — happy path with required fields only

- **Priority:** high
- **Preconditions:** Valid authentication credentials are available
- **Steps:**
  1. Send POST request to /pet
  2. Include only required parameters/fields with valid values
  3. Verify response status and body
- **Input:** `{"name":"Buddy","photoUrls":["https://example.com/photo.jpg"]}`
- **Expected Result:** Returns success response with expected data
- **Expected Status:** 200

## Negative Tests (2)

### TC-002: POST /pet — missing required field "name"

- **Priority:** high
- **Preconditions:** Valid authentication credentials are available
- **Steps:**
  1. Send POST request to /pet
  2. Omit required field "name"
  3. Verify error response
- **Input:** `{"_omit":"name"}`
- **Expected Result:** Returns validation error indicating "name" is required
- **Expected Status:** 422

### TC-003: POST /pet — invalid type for "name"

- **Priority:** medium
- **Preconditions:** Valid authentication credentials are available
- **Steps:**
  1. Send POST request to /pet
  2. Set "name" to invalid type value: 12345
  3. Verify error response
- **Input:** `{"name":12345}`
- **Expected Result:** Returns validation error for invalid type of "name"
- **Expected Status:** 422

The generator produces test cases across 8 categories (positive, negative, boundary, auth, business logic, security, idempotency, pagination) -- the example above shows just a small subset. Use generate_test_cases_batch to cover an entire API at once.

For detailed examples of every tool and workflow, see EXAMPLES.md.

Available tools

Generation config

All generation tools accept an optional config parameter:

{
  "config": {
    "categories": ["positive", "negative", "security"],
    "priorityFilter": ["high"],
    "maxFieldsForNegative": 15,
    "locale": "ru",
    "customPreconditions": ["Database seeded with test data"],
    "skipDeprecated": true
  }
}

Export to file

All exports are automatically saved to the working directory. The filename is generated from the endpoint and format:

test-cases_POST__pet_postman.json
test-cases_GET__users_testrail_csv.csv
test-cases_POST__orders_k6.js

You can also specify a custom path:

"Export as postman to /path/to/my-collection.json"