---

What it does

agentspec test app/main.py --base-url http://localhost:8000

agentspec v0.1.0

Discovering API endpoints...
  Discovered 9 endpoint(s) in Task Management API
Generating tests...
  Generated 128 test case(s)
Running tests against http://localhost:8000 (concurrency=10)...

 ✓ [CRITICAL] SQL injection in body field 'title'         39 ms  [201]
 ✓ [    HIGH] Wrong method PUT on /tasks                  25 ms  [405]
 ✓ [    HIGH] Content-Type matches expected on GET /tasks  31 ms  [200]
 ✓ [  MEDIUM] Enum value 'todo' for param 'status'        32 ms  [200]
 ✓ [  MEDIUM] Request with all optional params            44 ms  [200]
 ...

128 passed | 0 failed | 0 errors  (4314 ms)
██████████████████████████████ 100.0%

One command. Zero config. 128 tests.

---

What gets tested

For every endpoint agentspec discovers, it generates tests across five categories:

Category	What it checks
Happy path	Valid requests, all param combos, per-enum-value coverage
Edge cases	Empty strings, unicode, 10K-char strings, missing optional params
Error handling	Wrong HTTP methods, wrong types, unknown params, extra body fields
Security	SQL injection (8 variants), XSS, null bytes, path traversal, 1 MB payload bombs
Schema validation	JSON content-type, valid JSON body, response structure on every endpoint

---

Installation

pip install agentspec

Requires Python 3.10+.

---

Quick start

# Start your API
uvicorn app.main:app --reload

# Test it — framework is auto-detected
agentspec test app/main.py --base-url http://localhost:8000

Works with any framework:

# Flask
agentspec test api/app.py --base-url http://localhost:5000

# Express / NestJS / Fastify
agentspec test src/app.ts --base-url http://localhost:3000

# OpenAPI spec
agentspec test openapi.yaml --base-url http://localhost:8000

# Scan an entire directory
agentspec test ./src --base-url http://localhost:3000

---

Supported frameworks

Language	Framework	How it's discovered
Python	FastAPI	AST analysis
Python	Flask	AST analysis (Blueprints, MethodView, path converters)
Python	Django REST Framework	OpenAPI spec
JS / TS	Express.js	Regex analysis
JS / TS	NestJS	Decorator + controller analysis
JS / TS	Next.js (App Router)	Export handler + file path analysis
JS / TS	Fastify	Regex analysis
JS / TS	Hono	Regex analysis
Any	OpenAPI / Swagger	JSON or YAML spec

---

MCP server

Add agentspec to Claude Code, Codex, or Cursor so your AI agent can test APIs directly:

{
  "mcpServers": {
    "agentspec": {
      "command": "python",
      "args": ["-m", "agentspec.mcp.server"]
    }
  }
}

Available tools:

Tool	What it does
test_api	Discover, generate, and run all tests
discover_api	Discover endpoints without running tests
register_api	Test and register an API in the local registry
list_registered	List all registered APIs
check_compatibility	Detect breaking changes between API versions

Example — Claude Code:

You: test my API at http://localhost:8000 using app/main.py

Claude: [calls test_api]

→ 128 passed, 0 failed. Here's the full report...

---

CLI reference

agentspec test

agentspec test <source> --base-url <url> [options]

Options:
  --base-url TEXT      Base URL of the running API  [required]
  --concurrency INT    Parallel test runners (default: 10)
  --timeout FLOAT      Per-request timeout in seconds (default: 10.0)
  --format TEXT        text | json | html | junit (default: text)
  --output PATH        Write report to file
  --autofix            Show auto-fix suggestions for failures
  --watch              Re-run on source file changes
  --config PATH        Path to .agentspec.yaml

agentspec discover

Show all endpoints without running tests.

agentspec discover app/main.py

agentspec init

Generate a .agentspec.yaml config file.

agentspec init

agentspec register

Test and register an API in the local registry.

agentspec register app/main.py --base-url http://localhost:8000 --name "My API" --version 1.0.0

agentspec compat

Check for breaking changes between registered versions.

agentspec compat my-api:1.0.0 my-api:2.0.0

agentspec serve

Start the MCP server.

agentspec serve

---

HTML reports

agentspec test app/main.py --base-url http://localhost:8000 --format html --output report.html

Self-contained single-file HTML with donut chart, summary cards, sortable/filterable test table, and dark/light mode. No external dependencies.

---

Watch mode

Re-runs the full test suite whenever a source file changes:

agentspec test app/main.py --base-url http://localhost:8000 --watch

---

Auto-fix suggestions

agentspec test app/main.py --base-url http://localhost:8000 --autofix

When tests fail, the auto-fix engine analyzes failures and generates structured suggestions with code snippets — ready to apply directly or hand to your AI agent.

---

Config file

# .agentspec.yaml
base_url: http://localhost:8000
concurrency: 10
timeout: 10.0
format: text

skip_endpoints:
  - GET /health
  - GET /metrics

skip_categories:
  - security

# Env var expansion supported
headers:
  Authorization: "Bearer ${API_TOKEN}"
  X-API-Key: "${API_KEY}"

---

CI integration

# .github/workflows/api-tests.yml
name: API Tests
on: [push, pull_request]

jobs:
  test:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - uses: actions/setup-python@v5
        with:
          python-version: "3.12"
      - run: pip install agentspec fastapi uvicorn
      - run: uvicorn app.main:app --host 0.0.0.0 --port 8000 &
      - run: sleep 2
      - run: agentspec test app/main.py --base-url http://localhost:8000 --format junit --output results.xml
      - uses: actions/upload-artifact@v4
        with:
          name: test-results
          path: results.xml

---

API registry

agentspec keeps a local registry at ~/.agentspec/registry.json. Register multiple versions and diff them:

# Register v1
agentspec register app/main.py --base-url http://localhost:8000 --name myapi --version 1.0.0

# Register v2 after making changes
agentspec register app/main.py --base-url http://localhost:8001 --name myapi --version 2.0.0

# See what changed
agentspec compat myapi:1.0.0 myapi:2.0.0

---

Claude Code skill

Install the agentspec skill to teach Claude Code to automatically test APIs it generates:

cp -r skill ~/.claude/skills/agentspec

Once installed, Claude will suggest running agentspec after creating new endpoints and use auto-fix output to repair failures itself.

---

License

MIT