OpenRouter Known Pitfalls Overview A curated list of real-world mistakes developers make when integrating OpenRouter, each with the specific API behavior that causes the problem and the exact fix. These are not theoretical -- they come from production incidents and support requests. Pitfall 1: Missing Provider Prefix on Model ID Pitfall 2: No max tokens = Runaway Costs Pitfall 3: Hardcoded Model IDs Break When Models Are Renamed Pitfall 4: Fallbacks Route to Unexpected Providers Pitfall 5: Ignoring the Free Model Daily Limit Pitfall 6: Not Checking Which Model Actually Served the Request Pitf…