Semantic Ownership

Semantic ownership records concept-level responsibility across repository path patterns. It gives agents and operators a lightweight way to ask "who owns this area of meaning?" before they claim files, split work, or review overlapping changes.

The RFC-0010 implementation is advisory. It helps explain and route work, but it does not block Git operations, enforce hard locks, or replace GitNexus.

Persistence

Semantic graph state lives under the session/manifest root:

.metagit/
  graph/
    concepts.json
    ownerships.json
    ingest-hints.json   # optional operator-supplied input
  events/
    semantic.jsonl

concepts.json stores canonical concept rows such as authentication or billing. ownerships.json stores repository-scoped path patterns for each concept. Semantic lifecycle events append to .metagit/events/semantic.jsonl and appear in metagit context events with source: semantic.

Event kinds include:

Event	When emitted
ConceptDeclared	A manual or service declaration creates concept ownership
ConceptConflictHint	Multiple active ACL claim agents overlap one concept
ConceptIngested	Deterministic ingest adds ownership hints

CLI and MCP

CLI commands use the same session-root resolution as ACL commands. Pass --definition path/to/.metagit.yml when running outside the manifest root.

Goal	CLI	MCP tool
Declare concept ownership	metagit semantic declare --concept C --repository project/repo --pattern 'src/**' --json	metagit_semantic_declare
Query a concept	metagit semantic query --concept C --json	metagit_semantic_query
Resolve path owners	metagit semantic owners --repository project/repo --path src/file.py --json	metagit_semantic_owners
Show claim overlap hints	metagit semantic conflicts --repository project/repo --json	metagit_semantic_conflicts
Ingest deterministic hints	metagit semantic ingest --json	metagit_semantic_ingest
Seed the static catalog	metagit semantic seed --repository project/repo --json	Not exposed in MCP v1

MCP semantic tools are available only when the workspace gate is ACTIVE.

Advisory Claim Hints

ACL file claims remain advisory and Git remains authoritative. Semantic ownership adds a second, softer signal: when metagit claim check or MCP claim checks evaluate a path pattern, the result may include concept_hints for overlapping semantic ownership patterns.

These hints do not make the claim fail. They are intended for coordination:

• route a task to a likely concept owner;
• warn an agent that a claimed file belongs to a broader product concept;
• explain why two active claims may be related even when their file patterns do not directly collide.

Use metagit semantic conflicts --repository project/repo --json to find active ACL claims from multiple agents that overlap the same concept ownership.

Seed and Ingest

Semantic ownership is empty by default. Operators opt in to concept data.

metagit semantic seed --repository project/repo --json inserts a small static catalog of common concepts, with repository ownership patterns marked source: seed. Re-running the command is idempotent.

metagit semantic ingest --json reads deterministic hints from .metagit/graph/ingest-hints.json when present. A minimal hints file looks like:

{
  "ownerships": [
    {
      "concept": "Authentication",
      "repository": "platform/api",
      "patterns": ["backend/auth/**", "backend/login/**"]
    }
  ]
}

If the hints file is absent or empty, ingest returns success with reason: "no_ingest_signals". It does not call LLMs or infer ownership from repository contents.

Deferred GitNexus Import

Task 9 (semantic ingest --gitnexus) is deferred. RFC-0010 intentionally ships without a GitNexus import path; future work may add a read-only adapter that imports concept/path hints from GitNexus group or query results. Until then, operators should use manual declarations, the seed catalog, or ingest-hints.json.

Non-goals

• Semantic ownership is not a GitNexus replacement.
• Semantic ownership is not a source-code knowledge graph, vector index, or whole-repo semantic search engine.
• Semantic ownership does not enforce hard locks or block Git.
• Semantic ownership does not replace ACL branch leases, worktrees, or file claims.
• RFC-0010 does not implement RFC-0011 merge orchestration, RFC-0012 scheduling, or RFC-0013 AOS composition.