OpenRouter Common Errors

Overview

OpenRouter returns standard HTTP error codes plus OpenRouter-specific error codes in the response body. The most common: 401 (auth), 402 (credits), 429 (rate limit), 400 (bad request), and 5xx (upstream provider errors). Each error includes a code field and a human-readable message. This skill covers every common error, its root cause, and the exact fix.

Prerequisites

• An OpenRouter API key (sk-or-v1-...) exported as OPENROUTER_API_KEY — see the openrouter-install-auth skill for setup
• curl and jq to run the Diagnostic Script
• Python 3.8+ with the OpenAI SDK for the categorized error handler; Node.js 18+ for the TypeScript typed-error classifier in the references
• The requests package if you use the Prevention Middleware's pre-flight model check

Instructions