Your support assistant streams conversational replies to end users while calling get_account and create_ticket. In production, create_ticket intermittently receives malformed arguments (missing fields, wrong types) that crash the ticketing handler. Replies must stay streamed free-text prose, and p95 time-to-first-token must hold under 1.5 seconds. Which change most reliably eliminates the malformed tool calls?

1. AValidate the assembled tool_use JSON after content_block_stop and re-prompt Claude whenever validation fails.
2. BSet strict to true on the create_ticket definition so its arguments are validated against the input schema.
3. CAdd few-shot examples of valid create_ticket calls, wrapped in XML tags, to the system prompt.
4. DConstrain the full response with output_config format json_schema so every reply parses as valid JSON.