Key architectural choices behind the system:
• Read-Only Agent Boundaries: CrewAI agents research documents and portfolio context via a stdio MCP tool server restricted strictly to read and compute tools. Agents can analyze and propose, never approve or trade.
• Tamper-Evident Evidence Logs: Decision contexts are frozen with per-item SHA-256 hashes so historical replays never drift when underlying data changes.
• Payload-Bound Approval Gates: Orders require previewing, step-up re-authentication tied to the exact payload hash, and broker reconciliation.
• Lean Modular Monolith: Built with React, FastAPI, Docker, Ollama (qwen3:4b), and PostgreSQL 18 + pgvector handling relational state, vectors, full-text search, and FOR UPDATE SKIP LOCKED background jobs without Redis or Kubernetes bloat.