diff --git a/infra/build-server/discord-hooks/install.sh b/infra/build-server/discord-hooks/install.sh
index 25ae612b4..f8d5586db 100755
--- a/infra/build-server/discord-hooks/install.sh
+++ b/infra/build-server/discord-hooks/install.sh
@@ -1,6 +1,6 @@
 #!/usr/bin/env bash
 # Install or refresh the Discord webhooks scheduler on igneum-build-1 from this Mac.
-#   IGNEUM_SECRET_ON_BOX_OK=1 infra/build-server/discord-hooks/install.sh
+#   IGNEUM_SECRET_ON_BOX_OK=1 infra/build-server/discord-hooks/install.sh      (re-run whenever the credentials file changes)
 # Copies tools/community/discord-hooks.mjs to /srv/discord-hooks/bin, the webhook file ~/.config/igneum/discord to
 # /srv/discord-hooks/env (mode 600, owner build; never into the repository), the two units, and enables the timer.
 # Needs root over ssh (root@<ip> with ~/.ssh/igneum_ed25519); the host ip comes from ~/.config/igneum/build-server (build@<ip>).
@@ -16,9 +16,14 @@ HOST_LINE="$(head -1 "${IGNEUM_BUILD_HOST_FILE:-$HOME/.config/igneum/build-serve
 IP="${HOST_LINE#*@}"; [ -n "$IP" ] || { echo "no build server in ~/.config/igneum/build-server" >&2; exit 1; }
 [ "${IGNEUM_SECRET_ON_BOX_OK:-}" = "1" ] || { echo "refusing: the box holds no secret by rule; set IGNEUM_SECRET_ON_BOX_OK=1 once the coordinator has ruled the exception" >&2; exit 1; }
 [ -f "$CRED" ] || { echo "no credentials file at $CRED (DISCORD_WEBHOOK_NUMBERS, _ANNOUNCEMENTS, _INCIDENTS)" >&2; exit 1; }
+# a partial file is accepted (main's ruling, 6 October 2026, 20:1x UK): at least one key, the missing ones named here and
+# by every tick's log line; re-run this script when the other webhooks are created to copy the fuller file
+present=0; missing=""
 for k in DISCORD_WEBHOOK_NUMBERS DISCORD_WEBHOOK_ANNOUNCEMENTS DISCORD_WEBHOOK_INCIDENTS; do
-  grep -q "^$k=" "$CRED" || { echo "credentials file lacks $k" >&2; exit 1; }
+  if grep -q "^$k=." "$CRED"; then present=$((present + 1)); else missing="$missing $k"; fi
 done
+[ "$present" -ge 1 ] || { echo "credentials file has none of the three webhook keys" >&2; exit 1; }
+[ -z "$missing" ] || echo "note: missing${missing}; posts to those channels are logged, not sent, until the file is re-copied" >&2
 MODE="$(stat -f %Lp "$CRED" 2>/dev/null || stat -c %a "$CRED")"
 [ "$MODE" = "600" ] || { echo "credentials file must be mode 600 (is $MODE)" >&2; exit 1; }
 
@@ -30,5 +35,5 @@ scp -q -i "$KEY" "$ROOT/tools/community/discord-hooks.mjs" "build@$IP:/srv/disco
 scp -q -i "$KEY" "$HERE/igneum-discord-hooks.service" "$HERE/igneum-discord-hooks.timer" "root@$IP:/etc/systemd/system/"
 "${SSH[@]}" "root@$IP" 'systemctl daemon-reload && systemctl enable --now igneum-discord-hooks.timer >/dev/null 2>&1; systemctl is-active igneum-discord-hooks.timer; systemctl list-timers igneum-discord-hooks.timer --no-pager | sed -n 2p'
 # one check pass as the unit's user: names only, never values
-"${SSH[@]}" "build@$IP" 'IGNEUM_DISCORD_ENV=/srv/discord-hooks/env /usr/local/bin/node /srv/discord-hooks/bin/discord-hooks.mjs check'
+"${SSH[@]}" "build@$IP" 'IGNEUM_DISCORD_ENV=/srv/discord-hooks/env /usr/local/bin/node /srv/discord-hooks/bin/discord-hooks.mjs check' || true  # exit 1 on a partial file is the note above, not a failure
 echo "installed; the first tick runs within a minute: journalctl -u igneum-discord-hooks -n 20"
diff --git a/tools/community/discord-hooks.mjs b/tools/community/discord-hooks.mjs
index 1c67936be..dbb9bae58 100755
--- a/tools/community/discord-hooks.mjs
+++ b/tools/community/discord-hooks.mjs
@@ -560,6 +560,9 @@ export class Poster {
     this.state.posts = this.state.posts || {}; this.state.pulses = this.state.pulses || []; this.state.incidents = this.state.incidents || {}; this.state.watch = this.state.watch || {};
   }
   already(key) { return !this.force && !!this.state.posts[key]; }
+  // the webhook keys the credentials file lacks (names only); empty in dry run
+  missingKeys() { return this.live ? Object.values(CHANNEL_KEY).filter(k => !this.creds[k]) : []; }
+  has(channel) { return !this.live || !!this.creds[CHANNEL_KEY[channel]]; }
   // Posts one payload under an idempotency key; returns {posted, skipped, id}. Writes the dry-run JSON and preview in dry-run mode.
   async post(channel, key, payload) {
     const total = guardPayload(payload);
@@ -710,6 +713,12 @@ export async function resolveIncident(poster, { id, at, cause, fix }) {
 export async function runWatch(poster, data) {
   const actions = watchPass(data, poster.state);
   const results = [];
+  if (actions.length && !poster.has('incidents')) {
+    // the state still advances (no backlog flood when the key lands); the action is logged, not sent
+    for (const a of actions) poster.log(`watch: ${a.kind} ${a.id} not posted, no ${CHANNEL_KEY.incidents} in the credentials file`);
+    poster.save();
+    return [];
+  }
   for (const a of actions) {
     if (a.kind === 'open') results.push(await openIncident(poster, { id: a.id, at: a.at, what: a.what, affected: a.affected, doing: a.doing, auto: true }));
     else results.push(await resolveIncident(poster, { id: a.id, at: a.at, cause: a.cause, fix: a.fix }));
@@ -777,7 +786,8 @@ export async function main(argv = process.argv.slice(2)) {
     }
     const wdata = data && !data.fetchFailed ? data : await fetchForWatch();
     const r = await runWatch(poster, wdata);
-    poster.log(`tick ${ukStamp(now)}: ${due.length} due, watch ${r.length} action(s)`);
+    const missing = poster.missingKeys();
+    poster.log(`tick ${ukStamp(now)}: ${due.length} due, watch ${r.length} action(s)${missing.length ? `, missing ${missing.join(', ')}` : ''}`);
     return 0;
   }
   throw new Error(`unknown command ${cmd}`);
diff --git a/tools/community/discord-hooks.test.mjs b/tools/community/discord-hooks.test.mjs
index 0be48114c..9d43d4ac7 100644
--- a/tools/community/discord-hooks.test.mjs
+++ b/tools/community/discord-hooks.test.mjs
@@ -304,6 +304,24 @@ test('poster: live mode posts once, stores the message id, skips the rerun; the
   assert.equal(calls.length, 1);
   await assert.rejects(() => p.post('incidents', 'inc:x', payload), /no DISCORD_WEBHOOK_INCIDENTS/);
 });
+test('poster: a partial credentials file names its missing keys; the watcher advances its state and posts nothing without the incidents webhook', async () => {
+  const dir = tmpDir();
+  const cred = path.join(dir, 'discord'); fs.writeFileSync(cred, 'DISCORD_WEBHOOK_NUMBERS=https://discord.com/api/webhooks/1/secret\n', { mode: 0o600 });
+  const calls = [];
+  const fetchImpl = async (url, init) => { calls.push(url); return { ok: true, status: 200, headers: new Map(), json: async () => ({ id: '1' }) }; };
+  const logs = [];
+  const p = new Poster({ live: true, credFile: cred, stateFile: path.join(dir, 'state.json'), outDir: dir, log: m => logs.push(m), fetchImpl });
+  assert.deepEqual(p.missingKeys(), ['DISCORD_WEBHOOK_ANNOUNCEMENTS', 'DISCORD_WEBHOOK_INCIDENTS']);
+  assert.equal(p.has('numbers'), true); assert.equal(p.has('incidents'), false);
+  const { runWatch } = await import('./discord-hooks.mjs');
+  watchPass(data(), p.state, at(NOW, -60));
+  const lag = data(); lag.live.proving.median_proof_lag_s = 1000;
+  const r = await runWatch(p, lag);
+  assert.deepEqual(r, []);
+  assert.equal(calls.length, 0, 'nothing sent');
+  assert.match(logs.join('\n'), /open auto-proof_lag-\S+ not posted, no DISCORD_WEBHOOK_INCIDENTS/);
+  assert.ok(p.state.watch.proof_lag.open, 'the state still records the open, so the key landing later does not flood');
+});
 test('backoff: a 429 waits retry_after then doubles; success returns the id; six failures give up', async () => {
   const sleeps = [];
   let n = 0;