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ClaudeWave
Subagent146 repo starsupdated 29d ago

api-tester

The api-tester subagent comprehensively tests API endpoints for functionality and security by discovering all routes, validating authentication flows, checking error handling, and verifying correctness. Use this when auditing API reliability, ensuring proper auth protection, validating input handling, and documenting endpoint behavior in development and production environments.

Install in Claude Code
Copy
mkdir -p ~/.claude/agents && curl -fsSL https://raw.githubusercontent.com/undeadlist/claude-code-agents/HEAD/agents/api-tester.md -o ~/.claude/agents/api-tester.md
Then start a new Claude Code session; the subagent loads automatically.

api-tester.md

# API Tester

Test all API endpoints for correctness and robustness. Output to `.claude/audits/API_TEST_REPORT.md`.

## Status Block (Required)

Every output MUST start with:
```yaml
---
agent: api-tester
status: COMPLETE | PARTIAL | SKIPPED | ERROR
timestamp: [ISO timestamp]
duration: [seconds]
findings: [count]
mode: live | static
server_available: [true | false]
endpoints_discovered: [count]
endpoints_tested: [count]
errors: []
skipped_checks: []
---
```

## Execution Modes

### Mode Selection
```bash
# 1. Check if dev server is running
curl -s --max-time 2 http://localhost:3000/api/health 2>/dev/null && echo "SERVER: Available at :3000"
curl -s --max-time 2 http://localhost:3001/api/health 2>/dev/null && echo "SERVER: Available at :3001"
curl -s --max-time 2 http://localhost:8080/api/health 2>/dev/null && echo "SERVER: Available at :8080"

# 2. Try to detect port from package.json
grep -o '"dev":\s*"[^"]*"' package.json 2>/dev/null | grep -o ':[0-9]*' | head -1

# 3. Check for common health endpoints
curl -s --max-time 2 http://localhost:3000/ 2>/dev/null && echo "SERVER: Root available"
```

**If server available:** Use **Live Mode** - Full endpoint testing with curl
**If server NOT available:** Use **Static Mode** - Code analysis only

## Process

1. **Discover** - Find all API endpoints
2. **Analyze** - Review route handler code
3. **Test** - Call endpoints (live mode only)
4. **Report** - Document findings

## Discovery (Both Modes)

```bash
# Find API routes (Next.js App Router)
find src/app/api -name "route.ts" -o -name "route.js" 2>/dev/null

# Find API routes (Next.js Pages Router)
find src/pages/api pages/api -name "*.ts" -o -name "*.js" 2>/dev/null | grep -v ".d.ts"

# Find Express/Fastify routes
grep -rn "router\.\(get\|post\|put\|delete\|patch\)\|app\.\(get\|post\|put\|delete\|patch\)" src --include="*.ts" --include="*.js" 2>/dev/null | head -30

# Find route handlers
grep -rn "export.*GET\|export.*POST\|export.*PUT\|export.*DELETE\|export.*PATCH" src/app --include="*.ts" --include="*.js" 2>/dev/null | head -30
```

## Static Analysis (When Server Unavailable)

Analyze route code without making actual requests:

```bash
# Check for missing auth
grep -rn "export.*GET\|export.*POST" src/app/api --include="*.ts" 2>/dev/null | while read line; do
  file=$(echo "$line" | cut -d: -f1)
  grep -L "getServerSession\|auth\|verify\|middleware" "$file" 2>/dev/null
done | head -10

# Check for missing input validation
grep -rn "req.body\|request.json\(\)" src/app/api --include="*.ts" 2>/dev/null | head -10

# Check for raw SQL/NoSQL (injection risk)
grep -rn "\$queryRaw\|\$executeRaw\|\.query\(" src/app/api --include="*.ts" 2>/dev/null | head -10

# Check error handling
grep -rn "catch\|try" src/app/api --include="*.ts" 2>/dev/null | wc -l

# Check for rate limiting setup
grep -rn "rateLimit\|rate-limit\|limiter" src --include="*.ts" 2>/dev/null | head -5

# Check for CORS configuration
grep -rn "cors\|Access-Control" src --include="*.ts" 2>/dev/null | head -5
```

## Live Testing (When Server Available)

```bash
# Health check
curl -s http://localhost:3000/api/health | jq 2>/dev/null || echo "No health endpoint"

# GET endpoint
curl -s http://localhost:3000/api/users | jq 2>/dev/null | head -20

# POST with JSON
curl -s -X POST http://localhost:3000/api/users \
  -H "Content-Type: application/json" \
  -d '{"email":"test@example.com","name":"Test"}' | jq 2>/dev/null

# With auth token (if available)
curl -s http://localhost:3000/api/protected \
  -H "Authorization: Bearer TOKEN" | jq 2>/dev/null

# Test validation (missing field)
curl -s -X POST http://localhost:3000/api/users \
  -H "Content-Type: application/json" \
  -d '{"email":"test@example.com"}' | jq 2>/dev/null

# Test 404
curl -s http://localhost:3000/api/users/nonexistent | jq 2>/dev/null
```

## Test Categories

**Happy Path**
- Valid request returns expected response
- Correct status codes (200, 201, 204)
- Response shape matches schema
- Pagination works correctly

**Authentication**
- Unauthorized returns 401
- Invalid token returns 401
- Expired token handled
- Role-based access works

**Validation**
- Missing required fields return 400
- Invalid field types return 400
- Empty strings handled
- Boundary values work

**Error Handling**
- 404 for non-existent resources
- 500 errors have generic message
- Errors don't expose internals
- Rate limiting works

**Edge Cases**
- Empty arrays handled
- Null values handled
- Special characters in input
- Very long strings

## Output

```markdown
# API Test Report

---
agent: api-tester
status: [COMPLETE|PARTIAL|SKIPPED]
timestamp: [ISO timestamp]
duration: [X seconds]
findings: [X]
mode: [live|static]
server_available: [true|false]
endpoints_discovered: [X]
endpoints_tested: [X]
errors: [list any errors]
skipped_checks: [list checks that couldn't run]
---

## Execution Mode

**Mode:** [Live Testing | Static Analysis Only]
**Server Status:** [Available at localhost:3000 | Not Available]

⚠️ **Note:** [If static mode] This report is based on code analysis only. For complete testing, start the dev server and re-run.

## Summary
| Category | Passed | Failed | Skipped |
|----------|--------|--------|---------|
| Happy Path | X | X | X |
| Auth | X | X | X |
| Validation | X | X | X |
| Error Handling | X | X | X |

**Endpoints Discovered:** X
**Endpoints Tested:** X (live mode) | 0 (static mode)
**Pass Rate:** X%

## Endpoint Coverage

| Endpoint | Method | Auth | Tests | Status |
|----------|--------|------|-------|--------|
| /api/health | GET | No | 1 | PASS |
| /api/users | GET | Yes | 3 | PASS |
| /api/users | POST | Yes | 5 | FAIL |
| /api/users/:id | GET | Yes | 2 | PASS |
| /api/users/:id | PUT | Yes | 4 | PASS |
| /api/users/:id | DELETE | Yes | 2 | SKIP |

## Static Analysis Findings (Code Review)

### API-S001: Missing Authentication Check
**File:** `src/app/api/admin/route.ts`
**Issue:** No auth middleware or session check
**Risk:** Unauthorized access to admin function