Versioning & Deprecation
REST
REST paths carry v1. A breaking change to a documented path ships under a new path; the old path keeps answering. There is no /api/v2/ today, and none is implied by this policy — it's the rule for whenever one is needed.
MCP protocol
The MCP door speaks protocol versions 2024-11-05 and 2025-03-26.
The mega-tool catalog
Mega-tools and PRISM coordinates (mega_tool/app/entity/operation) are the stable agent contract. Discover them at runtime with prism_introspect rather than hardcoding a list — the catalog is versioned and permission-scoped underneath it.
Retiring a legacy tool name
A small set of standalone MCP tool names predates the mega-tools (see Compatibility tools). When one of those names is retired, it's removed from tools/list, and a call to the retired name returns a structured refusal carrying the replacement PRISM coordinate, a sunset date, and a hint to run prism_introspect(dimension="capability_search", …) to find the current equivalent. Retirements are announced on the changelog.
