Anthropic Claude API error
Anthropic API 529 overloaded_error: what it means and how to fix it
529 overloaded_errorRetry? YesLast verified 2 documented fixes2 sources
What it means
The API is temporarily overloaded.
Causes
- Temporary high load on the API
How to fix it
- Fix 1.
The official SDK automatically retries transient 5xx server errors with exponential backoff, twice by default; configure with max_retries.
Snippetclient = Anthropic( max_retries=0, # default is 2 ) - Fix 2.
Check the status page for ongoing incidents.
Seen in coding agents
These coding agent messages pass this Anthropic API error through. Each page has the agent-specific fix.
More Anthropic API errors
All 13 Anthropic API errors400 invalid_request_errorRetry? Not stated400 invalid_request_error (spend limit reached)Retry? Not stated401 authentication_errorRetry? Not stated402 billing_errorRetry? Not stated403 permission_errorRetry? Not stated404 not_found_errorRetry? Not stated409 conflict_errorRetry? Yes413 request_too_largeRetry? Not stated
HTTP 529 at other providers
Compare 529 across providersFAQ
What does the Anthropic API error "529 overloaded_error" mean?
The API is temporarily overloaded.
How do I fix Anthropic API "529 overloaded_error"?
There are 2 documented fixes. Start with the first: The official SDK automatically retries transient 5xx server errors with exponential backoff, twice by default; configure with max_retries.
Should I retry Anthropic API "529 overloaded_error"?
Yes. The official docs treat this error as retryable.
Which other AI APIs return HTTP 529?
Per their official error docs: Amazon Bedrock (529 overloaded_error).
Sources
Last verified against 2 sources: Anthropic API's official docs and official SDK repositories.
- platform.claude.comhttps://platform.claude.com/docs/en/api/errors
- status.claude.comhttps://status.claude.com
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