Agent-skills-standard nestjs-error-handling

Implement Global Exception Filters and standard error formats in NestJS. Use when implementing global exception filters or standardizing error responses in NestJS. (triggers: **/*.filter.ts, main.ts, ExceptionFilter, Catch, HttpException)

install

source · Clone the upstream repo

git clone https://github.com/HoangNguyen0403/agent-skills-standard

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

T=$(mktemp -d) && git clone --depth=1 https://github.com/HoangNguyen0403/agent-skills-standard "$T" && mkdir -p ~/.claude/skills && cp -r "$T/skills/nestjs/nestjs-error-handling" ~/.claude/skills/hoangnguyen0403-agent-skills-standard-nestjs-error-handling && rm -rf "$T"

manifest: skills/nestjs/nestjs-error-handling/SKILL.md

source content

NestJS Error Handling Standards

Priority: P1 (OPERATIONAL)

Requirement: Centralize error formatting.
Platform Agnostic: not import
```
Request
```
/
```
Response
```
from Express/Fastify types directly.
Use:
```
HttpAdapterHost
```
to access underlying platform response methods.

const { httpAdapter } = this.httpAdapterHost;

Structure:
Implement strictly typed error responses.
Refer to API Standards for
```
ApiErrorResponse
```
.

 {
   "statusCode": 400,
   "message": "Validation failed",
   "error": "Bad Request",
   "timestamp": "ISO...",
   "path": "/users"
 }

Error Flow

Service: Throws specific or generic errors (e.g.,
```
EntityNotFoundError
```
).
Interceptor: Maps low-level errors to HTTP Exceptions (e.g.,
```
catchError(err => throw new NotFoundException())
```
).

Why: Keeps Exception Filters focused on formatting, not business logic interpretation.

Global Filter: Formats final JSON response.

Built-in Exceptions

Use: Throw

NotFoundException

ForbiddenException

BadRequestException

Custom: Extend
```
HttpException
```
only for domain-specific failures that need specific status codes.

Logging

Context: Always pass
```
MyClass.name
```
to
```
Logger
```
constructor.
Levels:
```
error
```
: 500s (Stack trace required).
```
warn
```
: 400s (Client errors).

Security (Information Leakage)

Production: NEVER expose stack traces in HTTP responses (
```
process.env.NODE_ENV === 'production'
```
).
Sanitization: Ensure
```
ApiException
```
payloads not leak internal file paths or raw variable dumps.

Anti-Patterns

No stack traces in production: Gate stack exposure behind
```
NODE_ENV === 'production'
```
check.
No Express types in filters: Use
```
HttpAdapterHost
```
for platform-agnostic error handling.
No HttpException in services: Throw domain errors in services; let Interceptors map to HTTP exceptions.