Name the CultMesh MCP bridge as a priority campaign

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

src/GameCult.Mesh/docs/mcp-bridge-campaign.md

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+# CultMesh MCP Bridge: Priority Campaign
+
+Date: 2026-09-18
+
+Status: named, not started. Operator (2026-09-18): "I'm kind of surprised we
+don't have a generic CultMesh MCP bridge" / "Note it in CultLib as a priority
+campaign, but yes, for another day". No cut map, no branch, nobody assigned.
+
+## The gap
+
+Nothing in GameCult bridges CultMesh to MCP. The only first-party MCP server is
+VoidBot's retrieval server (repos, Discord history); every other MCP hit under
+`F:\Projects` is a vendored copy inside stale `Epiphany\.epiphany-run` sandboxes.
+
+So an agent that wants to read a daemon's state or drive it has no general path.
+Each daemon needs bespoke tooling, which is why nobody has any.
+
+## What made it urgent
+
+Aetheria needs an editor rigged: create an object, attach a component, set a
+transform, point a field at an asset. Brokkr (`F:\Projects\Brokkr`) already
+executes exactly those commands in Unity as a CultMesh provider
+(`surfaces/unity/Packages/com.gamecult.brokkr/Editor/BrokkrUnityCommandExecutor.cs`:
+`createGameObject`, `attachComponent`, `setGameObjectTransform`,
+`setGameObjectParent`, `setComponentProperty`, `instantiatePrefab`,
+`createPrefabVariant`, `assignMaterial`, `createScriptableObject`), publishes a
+host snapshot, and returns typed receipts. An agent still cannot send one: the
+daemon has no CLI, and its surface is CultMesh documents.
+
+The alternatives an agent falls back to are both bad, and both have drawn blood
+in Aetheria: hand-edited scene YAML (a bad `sed` prefixed every line of a
+committed map, `Aetheria 78fd617c`), or a one-shot editor script written blind
+against a scene nobody can see.
+
+Brokkr-specific tooling would treat the symptom. The missing organ is general.
+
+## Why the contract is already there
+
+`cross-runtime-primitives-roadmap.md` names MCP as a consumer three times, and
+the two primitives a bridge needs are already specified there:
+
+- **typed state pointer** — a stable typed reference that resolves, watches, and
+  carries route hints and source schema (`:72-73`);
+- **operation binding descriptor** — a typed operation id with request schema and
+  route hints (`:75`).
+
+A bridge lowers those, the way Eve lowers a composition graph. It does not invent
+a second description of what a provider offers.
+
+## Shape to map
+
+- **Tools:** discover providers and surfaces (through Odin, the organ that
+  already aggregates them); resolve and watch typed state at a pointer; invoke an
+  operation and return its typed receipt.
+- **MCP is a xenos boundary,** so JSON lives there and only there. Authority stays
+  typed CultMesh state behind it.
+- **Admission.** A read-only bridge is cheap. The moment it invokes operations it
+  can mutate live Verse state, and it takes the same admission and receipt path as
+  any other caller. It does not get a private door.
+
+## Open, for the pass that takes this
+
+- Where it lives: beside the Rust CultMesh in CultLib, inside Odin, or its own
+  repo.
+- Whether watches can reach an MCP client at all, or whether the first cut is
+  resolve-and-invoke with polling.
+- What a provider must publish before it is usable through the bridge, and whether
+  Brokkr already publishes it.