DL-264
The DL-053 agent-notification transport is WEBHOOK-ONLY: a per-deployment GitHub App (one App-level webhook URL + secret, install-to-subscribe, X-Hub-Signature-256 fail-closed) posting to POST /webhooks/github on the network TLS door, and Linear Issue/Comment data-change events on the RIG-2717 POST /webhooks handler (implementation in flight — Global Constraints) — no standing poll loop exists on this lane. Reliability is a bounded reconciliation catch-up: one conditional-GET sweep at startup plus a 30 min backstop that diffs snapshots via DetectChanges and re-notifies from the durable delivered_revision gap (synthesizing one payload-free UPDATE when the missed set is no longer derivable) — a gap-healer at tens-of-minutes cadence, never a primary transport. Supersedes DL-053’s transport premise; its two-cursor split and delivery semantics survive.
Status: Active (Matt, 2026-08-26)