diff --git a/sidecar/src/main.rs b/sidecar/src/main.rs
index 347869f..bfaaaa4 100644
--- a/sidecar/src/main.rs
+++ b/sidecar/src/main.rs
@@ -52,7 +52,27 @@ use tracing_subscriber::EnvFilter;
 /// kinds are new, `GET /guilds` grows a `roster` key, and nothing existing changed shape. This is the
 /// first bump that also needed a **store migration** (`guilds.members`), because it is the first to
 /// add a column to a table that already exists rather than a whole new table; see `store::migrate`.
-pub const PROTOCOL_VERSION: u32 = 4;
+///
+/// v5 (Protocol 5): three enrichments that are additive in the same way again, bumped together
+/// rather than one at a time because a protocol bump is not cheap here — it costs a sidecar
+/// release, a republished bundle and an operator update on every shard, so a field left out costs
+/// a whole second round of that rather than a follow-up commit. They are:
+///
+///   * `house.decay` gains `ownerName` and a decay SCHEDULE — `nextStage`, `decayPeriodSec`,
+///     `dynamicDecay`, and `estimatedCollapse` only where it is exactly knowable (at IDOC under
+///     dynamic decay; at any stage under static decay, which has no randomness to wait out).
+///   * `vendor.listing` gains `ownerAcct` — without which the frame names an owner nobody can
+///     resolve to a person — and a `fees` object carrying the charge, the funds, the pay interval
+///     and the resolved `dismissalAt`.
+///   * `account.login.result` is a NEW kind: the verdict of a login, which the pre-existing
+///     `account.login.attempt` structurally cannot carry (its EventSink fires before the auth
+///     decision is made).
+///
+/// **No store migration this time**, unlike v4. Every frame is persisted whole and the board tables
+/// index only the columns they already had, so the new fields ride inside the stored JSON and the
+/// new kind lands in `events` like any other. That is the dumb-forwarder property doing its job:
+/// the sidecar defines no schema for a frame's contents and so needs no change when they grow.
+pub const PROTOCOL_VERSION: u32 = 5;
 
 // Not `#[tokio::main]`: on Windows the SCM dispatcher takes over this thread and starts the runtime
 // itself, on its own thread, once the service actually begins. The runtime is built by whichever