ReadonlyargumentsRaw JSON string exactly as the model produced it — never re-parsed in transit.
Optional ReadonlygeminiReadonlyidCall join key; Gemini metadata distinguishes an optional wire id from a local key.
ReadonlykindReadonlynameOptional ReadonlyproviderDecoded provider name before request-scoped binding; not raw HTTP bytes.
A tool invocation requested by the model.