ModelToolResultBlock
Parameters and properties
Section titled “Parameters and properties”typeRequired"tool-result"Block discriminator: tool-result.callIdRequiredstringIdentifier of the tool call this result answers.contentRequiredstringText returned to the model for this call.isErrorOptionalboolean | undefinedMarks the result as a failed tool execution. Only Anthropic transmits it, as is_error; OpenAI protocols send the content alone.