Skillshub handling-api-errors

install

source · Clone the upstream repo

git clone https://github.com/ComeOnOliver/skillshub

Claude Code · Install into ~/.claude/skills/

T=$(mktemp -d) && git clone --depth=1 https://github.com/ComeOnOliver/skillshub "$T" && mkdir -p ~/.claude/skills && cp -r "$T/skills/jeremylongshore/claude-code-plugins-plus-skills/handling-api-errors" ~/.claude/skills/comeonoliver-skillshub-handling-api-errors && rm -rf "$T"

manifest: skills/jeremylongshore/claude-code-plugins-plus-skills/handling-api-errors/SKILL.md

Handling API Errors

Overview

Implement standardized API error handling with RFC 7807 Problem Details responses, centralized error middleware, typed error classes, and environment-aware stack trace exposure. Convert framework exceptions, validation failures, database errors, and upstream service failures into consistent, machine-readable error responses with appropriate HTTP status codes.

Prerequisites

Web framework with middleware/error handler support (Express, FastAPI, Spring Boot, Gin)
Structured logging library for error event recording with correlation IDs
Error monitoring service: Sentry, Bugsnag, or Rollbar for production error tracking
RFC 7807 Problem Details specification for response format guidance
API documentation listing all possible error codes and their meanings

Instructions

Audit existing error handling using Grep to find
```
try/catch
```
blocks, error middleware, and exception handlers, identifying inconsistent error response formats across endpoints.
Define a standardized error response envelope following RFC 7807:
```
type
```
(URI identifying error type),
```
title
```
(human-readable summary),
```
status
```
(HTTP code),
```
detail
```
(specific explanation), and
```
instance
```
(request path).

Create typed error classes for each error category:

ValidationError

(400),

AuthenticationError

(401),

AuthorizationError

(403),

NotFoundError

(404),

ConflictError

(409), and

RateLimitError

(429).

Implement centralized error handling middleware that catches all thrown errors, maps them to the appropriate HTTP status code and RFC 7807 body, and prevents raw stack traces from leaking to clients.
Add validation error formatting that transforms framework-specific validation failures into a consistent array of field-level errors with
```
field
```
,
```
message
```
, and
```
code
```
properties.
Configure environment-aware error detail: include stack traces and internal error codes in development/staging responses; omit them in production while logging the full error server-side.
Integrate error monitoring (Sentry/Bugsnag) that captures 5xx errors with full context (request details, user info, stack trace) and groups them by root cause for triage.
Handle unhandled rejections and uncaught exceptions at the process level, returning 500 with a generic error message while logging the full failure and triggering alerts.
Write tests verifying that each error type produces the correct HTTP status code, RFC 7807 response body, and that stack traces are hidden in production mode.

See

${CLAUDE_SKILL_DIR}/references/implementation.md

for the full implementation guide.

Output

```
${CLAUDE_SKILL_DIR}/src/errors/
```
- Typed error classes (ValidationError, NotFoundError, etc.)

${CLAUDE_SKILL_DIR}/src/middleware/error-handler.js

- Centralized error handling middleware

${CLAUDE_SKILL_DIR}/src/errors/formatters.js

- Error-to-RFC-7807 response transformation

```
${CLAUDE_SKILL_DIR}/src/errors/codes.js
```
- Error code registry with human-readable descriptions

${CLAUDE_SKILL_DIR}/src/config/error-config.js

- Environment-aware error detail configuration

```
${CLAUDE_SKILL_DIR}/tests/errors/
```
- Error handling tests for each error type and scenario

Error Handling

Error	Cause	Solution
Stack trace leaked	Error handler omits production check; raw Error thrown without wrapping	Verify `NODE_ENV` / `APP_ENV` check in error formatter; wrap all thrown errors in typed classes
Inconsistent error format	Some endpoints return `{error: "msg"}` while others return RFC 7807	Ensure all errors flow through centralized middleware; remove per-handler try/catch that formats differently
Unhandled promise rejection	Async handler throws without catch; Express does not catch async errors	Use `express-async-errors` wrapper or explicit async error forwarding with `next(err)`
Database error exposed	Raw SQL error message returned to client containing table/column names	Map database errors to generic messages at the error handler layer; log full details server-side
Error monitoring noise	High volume of expected 4xx errors flooding Sentry/Bugsnag	Configure error monitoring to capture only 5xx; track 4xx via metrics, not error monitoring

Refer to

${CLAUDE_SKILL_DIR}/references/errors.md

for comprehensive error patterns.

Examples

RFC 7807 response:

{"type":"https://api.example.com/errors/validation","title":"Validation Error","status":400,"detail":"Request body contains 2 validation errors","errors":[{"field":"email","message":"Invalid email format","code":"INVALID_FORMAT"}]}

Centralized Express error handler: Single

app.use((err, req, res, next) => {...})

middleware that handles all error types, sets status codes, formats RFC 7807 bodies, logs with correlation ID, and reports to Sentry.

Graceful upstream failure: When a downstream payment service returns 500, wrap it in a

ServiceUnavailableError

with a user-friendly message, log the upstream response for debugging, and trigger a circuit breaker.

See

${CLAUDE_SKILL_DIR}/references/examples.md

for additional examples.

Resources

RFC 7807 Problem Details for HTTP APIs: https://tools.ietf.org/html/rfc7807
Sentry error monitoring: https://sentry.io/
Express error handling best practices
HTTP status code decision tree for API responses