404 Not Found

The requested resource could not be found but may be available in the future. Subsequent requests by the client are permissible.

Agenzia per l'Italia Digital & Team per la trasformazione digital (Italian administration) - Interoperability model for the Public Administration

REST interface processing rules

Atlassian - Atlassian REST API Design Guidelines version 1

Appendix A: Response Codes

Australian Digital Transformation Office - API Design Guide

GET /magazines

Cloud Foundry - Cloud Controller API v3 Style Guide (Proposal)

Client Errors

Deliveroo - API Design

RESTful

DELETE, destroying entities

404 Not Found if the entity does not exist

Return codes and errors

404 Not Found: the specified entity does not exist (unknown routes should not 404).

Caching

Responses with the following status codes should specify a Cache-Control header

Haufe - Haufe API style guide

HTTP Status (Get List of resources)

HTTP Status (Read Single Resource)

Delete Single Resource

404 Not Found HTTP status should not be utilized

HTTP Status Codes

PayPal - API Style Guide

HTTP Status (Collections)

HTTP Status (Read Single Resource)

Update Single Resource

Delete Single Resource

Zalando - RESTFul API Guidelines

Client Side Error Codes

adidas - adidas API design guidelines

Security