Fix guides, by the error you got
Rate-limit and overload errors by their exact text: what the vendor’s docs say each one means, the retry rule, and the fix on a key that fails over at the same price with limits per key.
Claude Code: API Error: Rate limit reached
the 429 behind "API Error: Rate limit reached" in Claude Code, the retry-after rule, and the two-variable switch to a key with its own limits
OpenRouter 429: Provider returned error
what OpenRouter's 429 "Provider returned error" means per its docs, the free-model caps, and a base-URL switch to a key that fails over
Gemini API 429 RESOURCE_EXHAUSTED
Google's 429 RESOURCE_EXHAUSTED, the RPM / TPM / RPD dimensions behind it, exponential backoff, and Gemini on a key with per-key limits
Anthropic 529 overloaded_error
Anthropic's 529 overloaded_error, why a retry alone is not a fix, and Claude on a key that tries the next route before you see it
OpenRouter: No endpoints found
the 404 "No endpoints found" from OpenRouter, its tool-use variant, and a catalog where every listed id has a route
A key that fails over, with limits you set
From the OpenAPI document, read 2026-10-31.
- Failover before you see it
- A route that fails with a 5xx or a 429 is retried on the next route for the same model. x-uplink-attempts on the answer counts the tries; the price is the model’s own either way.
- Your own fallback list
- models: [...] names up to 5 models tried in order once every route of the one before has failed before a byte was sent. Each bills at its own price when it answers.
- Failed requests are not charged
- A 429, 502 or 503 from this API charges nothing and carries retry-after: back off that long before trying again.
- Limits per key, set by you
- rpm from 1 to 100,000, tpm from 1 to 50,000,000 and concurrency from 1 to 10,000 on each key. Default: 600 requests a minute per key, 50 in flight per account.
- A budget per key
- budget_usd plus a daily, weekly or monthly spend limit. The key stops at its own line with a 402; the rest of the balance is untouched.
- One request id
- x-uplink-request-id on every answer, errors included. Quote it and we find the call.
A key that does not stop at one host
Failover at the same price, limits and a budget per key, failed requests not charged. Card or crypto, no KYC, no subscription.