Errors and retries

Errors follow the compatibility surface used by the request: OpenAI-shaped for Chat Completions and Responses, and Anthropic-shaped for Messages.

Status	Meaning	Recommended action
`400`	Invalid request or invalid provider key configuration	Correct the request or provider-key configuration.
`401`	Missing or invalid Tokenless API key	Verify the credential and authentication header.
`402`	No available account credit	Add credit in the dashboard.
`429`	Rate limited	Retry with exponential backoff and jitter.
`503`	No upstream candidate currently available	Retry with exponential backoff and jitter.
`529`	Temporarily overloaded	Respect `Retry-After`, then retry.

Do not automatically retry malformed requests, authentication failures, or invalid provider-key errors. For temporary failures, cap the number of retries and include jitter to avoid synchronized retry spikes.

Correlation

Capture the X-Request-Id response header whenever present. It is the most useful identifier when investigating a request with Tokenless support.

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Tokenless CLI

OpenAI API

Anthropic API

Cost & usage

BYOK

Reference

Errors and retries

Correlation

​Correlation

Correlation