Plain-terms companion to integration-architecture.md: Automation Hub as the
internal action warehouse, Tool Hub as the smart front desk (progressive
disclosure + per-user permission filtering + audit) running as a central
service, and where the MCP Gateway (Arcade, per-user OAuth for outside tools)
and AI Gateway (config-only model toll booth) plug into existing seams.
Source-verified against servicetitan/tool-hub + automation-hub @ master.
Where the AI Gateway (LLM proxy) and MCP Gateway (Arcade) fit into the
Agent Platform -> Tool Hub -> Automation Hub stack without major work on
either app: AI Gateway = config repoint; Arcade = Tool Hub's existing
mcp_proxy adapter seam, with per-user OAuth living in Arcade. Includes
GitHub-renderable mermaid topology + sequence diagrams and a change-surface
table, grounded in tool-hub + automation-hub source reads.
Tejus Rachakonda
ztaylor