OptionalidProvider call id of the invocation this answers.
OptionalisProvider-reported error flag.
Absent means the store records no error signal at all — NOT success.
Claude marks is_error on every tool result; Codex records no equivalent,
so Codex results always leave this undefined. Reading absence as a pass
would count "not observable" as "worked", which is the failure mode that
lets an eval report health it never measured.
OptionalnameTool name, only when the store records one on the result itself.
The outcome of one tool invocation. The tool NAME generally lives on the call, not the result, so joining on PromptToolResult.id is what identifies which tool failed.