result_unavailable is a 409 from a callable invocation's result endpoint. The stored result cannot be encoded within the endpoint's supported representation. The invocation may have succeeded; this read error does not rerun it or rewrite its result.

This can happen when one number would expand beyond 64 MiB in canonical decimal notation, or when older stored text contains a lone surrogate or U+0000. The numeric ceiling applies to each number, not to the total result size. The error does not return the affected value or field contents.

Recovery guidance

Keep the invocation ID and the error's requestId, and read the existing invocation's status. Repeatedly downloading the same stored result will not repair its representation. Do not start another invocation as a download retry: that creates new work rather than recovering this result.

Ask your workspace administrator or support to investigate the existing result using those IDs. For future calls, review and test the Job's output definition. If an extremely large number is intentional, consider a string field in a new Job version. Publishing a new version does not change a historical result.