Document Processing Analyst — P0 Pre-Wave Subagent for Client Document Extraction

[Number531]

Document Processing Analyst — P0 Pre-Wave Subagent

New subagent that processes client-uploaded documents before research planning begins. Extracts text, analyzes content, identifies critical issues, and maps documents to specialist domains.

Full spec: docs/pending-updates/document-extractor-agent.md

Key Facts

• Scope: ~1,500 new lines across 12 files (6 new, 6 modified)
• Risk: HIGH (65-75%) without 3 mandatory mitigations → 0% with mitigations applied
• Dependencies: None (fully additive)
• Feature flag: Document-conditional — only activates when documents.length > 0

Implementation Phases

1. Frontend upload UI (file input, drag-and-drop, FormData transport)
2. Session initialization (sessionInitializer.js, multer middleware, 3 mandatory mitigations)
3. Subagent definition (legalSubagents.js, PARALLEL_EXECUTION_GROUPS)
4. SDK hooks & SSE bridge updates
5. Prompt updates (roles.md, completion.md, waves-execution.md, state-file-schemas.md)
6. Orchestrator integration (manifest reading, P0 invocation, enhanced research plan)
7. Specialist updates (document citation format, fact registry schema)
8. Testing (backward compat for query-only sessions is critical)

Mandatory Mitigations (spec §Breaking Risk Assessment)

1. Add 'initial-query-docs', 'documents' to KNOWN_SUBDIRS
2. All manifest reads use existsSync() + null-check
3. initializeSession() only called when documents.length > 0

[Number531]

Resolved in v3.5.3

The document processing pipeline has been merged from feature/document-extractor-agent and enabled by default (DOCUMENT_PROCESSING=true).

What shipped

• P0 subagent (document-processing-analyst) — extracts, analyzes, and maps uploaded documents before research planning
• Frontend upload UI — drag-and-drop, drag-reorder, file size indicators, undo-clear
• Session initializer — multer middleware, initial-query-docs/ directory, extraction manifest
• Hooks & SSE bridge — document processing events forwarded to dashboard timeline
• Prompt updates — roles, completion, waves-execution, state-file-schemas updated for P0 workflow
• Reports modal — now serves DOCX/PDF from conversion manifest

Safety

• Document-conditional: only activates when documents.length > 0
• All 3 mandatory mitigations applied (KNOWN_SUBDIRS, existsSync guards, conditional init)
• Rollback: DOCUMENT_PROCESSING=false (zero behavior change)

Commits

• 347589e Merge branch 'feature/document-extractor-agent'
• Phases 1–6 implemented across 12 files (~1,500 new lines)

Closes #8.