diff --git a/.upstream-provenance.json b/.upstream-provenance.json
new file mode 100644
index 000000000..413ba068c
--- /dev/null
+++ b/.upstream-provenance.json
@@ -0,0 +1,6 @@
+{
+  "true_upstream": "https://github.com/Egonex-AI/Understand-Anything",
+  "true_upstream_branch": "main",
+  "last_synced_upstream_sha": "2cda14e89535049e49120198886bc0b82e9e630f",
+  "note": "Provenance marker for the CircuitBoardGames/ClaudeCode maintainer agent's P2 vendor-sync drift check (docs/agents/maintainer.md Part A.6a). last_synced_upstream_sha is this fork's merge-base with true_upstream at seed time; advance it in each true-upstream->fork sync PR. Seeded 2026-07-29, later than the other three forks (which were seeded per ClaudeCode issue #46) because this fork carried no divergence until then and link (a) was explicitly documented as not-runnable for it; see docs/agents/ua-fork-plan.md. This fork's divergence is PERMANENT and is not offered upstream, so sync upstream by rebasing that divergence forward -- never blind-merge. One hazard specific to this fork: an upstream sync can move pnpm-lock.yaml, and a grammar re-resolving to a version with no musl prebuild turns a later install into a multi-MB g++ compile, so review lockfile changes in a sync PR rather than waving them through."
+}