tessl-labs/express-error-handling
Production error handling for Express APIs — error middleware, async wrappers,
89
86%
Does it follow best practices?
Impact
97%
2.02xAverage score across 4 eval scenarios
Passed
No known issues
Evaluation results
100%
61%Build a Bookstore Inventory API
Global error middleware
0%
100%
Async error safety
66%
100%
Structured error response format
25%
100%
No stack trace leaks
66%
100%
Custom error classes
0%
100%
404 catch-all handler
0%
100%
Graceful shutdown
0%
100%
Appropriate status codes
80%
100%
CRUD endpoints functional
100%
100%
98%
52%Build an E-Commerce Orders API
Global error middleware
0%
100%
Async error safety
50%
100%
Structured error responses
58%
100%
No internal error leaks
30%
100%
Validation with details
70%
100%
Not-found handling
100%
100%
Business rule error handling
87%
100%
404 catch-all
0%
71%
Graceful shutdown
0%
100%
Appropriate status codes
70%
100%
98%
46%Build a Task Management API
Global error middleware
0%
100%
Async error safety
100%
100%
Structured error responses
50%
100%
No stack trace leaks
70%
100%
Typed error classes
0%
100%
Validation errors
90%
100%
Not-found handling
100%
100%
404 catch-all
0%
71%
Graceful shutdown
0%
100%
CRUD endpoints functional
100%
100%
93%
38%Build a Weather Proxy API
Global error middleware
0%
100%
Async error safety
50%
100%
External errors mapped to HTTP responses
100%
100%
No raw error messages to client
33%
100%
Structured error format
100%
100%
404 catch-all for unknown routes
100%
75%
Graceful shutdown
0%
100%
Input validation
0%
37%
Weather endpoint functional
100%
100%
- Evaluated
- Agent
- Claude Code
- Model
- Claude Sonnet 4.6