When a model fallback causes structured output to be retracted and no retry succeeds, Claude Code now surfaces a more specific error message instead of the previous "the cloud agent called StructuredOutput but every attempt failed schema validation."
New message: "the cloud agent called StructuredOutput but no attempt produced a surviving valid output (failed schema validation, or retracted by a model fallback)"
Evidence
Updated error string (search for "retracted by a model fallback and no retry produced a valid result")
Strings lifted out of the shipped bundle, so the claim above can be checked against them.
