Q2 of 60 — CCA Practice Exam

Structured Data Extraction

Your structured data extraction pipeline uses an MCP tool named mcp__crm__write_record to persist extracted contract fields back to the CRM. After deploying, you observe that roughly 12% of write operations are immediately retried by the agent — logs show the agent receiving a deny response but then re-attempting the same write within the same session. The PreToolUse hook correctly identifies and blocks writes containing invalid contract_id formats, but the agent keeps retrying. What is the most effective fix?

A. Change the hook's matcher from mcp__crm__write_record to an unscoped pattern so it fires for all tool calls, giving the agent more opportunities to intercept invalid data before a write is attempted.

B. Add a systemMessage field to the hook's deny response that explains why the contract_id format is invalid and what a valid format looks like, so the agent receives actionable context and stops retrying.

C. Replace permissionDecision: 'deny' with a post-processing step that silently drops invalid writes after they execute, so the agent receives a success response and does not attempt retries on the same record.

D. Move the contract_id format validation out of the hook and into the system prompt, instructing Claude to validate all extracted fields before calling mcp__crm__write_record on any contract record.