MCP Is the Coordination Plane

Rule

Work tracking and activity coordination are MCP records, written by every delivery surface, regardless of Build Studio. The DPF MCP substrate is the executor-agnostic source of truth:

The rule: if it isn’t in the MCP plane, it didn’t happen.

Why

Three surfaces can only be peers if there is one place that knows what each is doing. The chaos observed on the live install (2026-06-05) — 119 worktrees nobody reaps, generations of orphaned sidecars, ad-hoc CI images — traces to a registration gap, not a path difference: work happened without ever being claimed or recorded, so coordination had nothing to coordinate against. A surface that does work invisibly cannot be de-conflicted, reaped, resumed, or audited. The MCP plane is also what makes a gate provenance-agnostic (governance-approves-evidence-not-provenance): the gate reads MCP evidence, not the surface’s private state.

The sidecars that sessions spawn must be the DPF MCP (/api/mcp/v1 via DPF_MCP_BEARER_TOKEN), not generic npx servers (xcodebuildmcp, youtube-transcript-mcp). A session wired to generic MCP servers instead of DPF’s does not coordinate through the substrate at all.

How To Apply

Decision Dimensions

Origin

Unified Delivery Surfaces spec, 2026-06-05 (WWMD-ratified).