Tasks

1. Implementation

• 1.1 Add retrieval-mode attachment tags and reminders to context construction.
• 1.2 Add session attachment RAG tools to buildToolsForSession.
• 1.3 Remove generation-time automatic pre-query evidence injection.
• 1.4 Allow sending while retrieval attachments are indexing or failed so the model can respond from tool-visible status.
• 1.5 Add PoC eval script for model tool-use behavior.
• 1.6 Create separate local fixture repository with synthetic documents and cases.

2. Verification

• 2.1 Add unit coverage for retrieval attachment context tags.
• 2.2 Add unit coverage for session attachment RAG tool registration.
• 2.3 Run target unit tests.
• 2.4 Run eval harness against a real model endpoint.