diff --git a/CLAUDE.md b/CLAUDE.md
index 1b2e8a0..878be52 100644
--- a/CLAUDE.md
+++ b/CLAUDE.md
@@ -219,6 +219,7 @@ UP Board enumerates its eMMC controller via ACPI, not PCI. `upboard.nix` force-l
 ## Useful invariants when debugging
 
 - The renderer logs prefix every line with a tag: `[Lightning]`, `[ATM]`, `[ATM Service]`, `[LNURL Session]`, `[CLINK]`, `[StateStore]`. `journalctl -u bitspire | grep '\['` is your friend.
+- **Never pass an object as a console argument in the renderer.** Electron's console bridge stringifies each argument, so `console.log('msg:', { a, b })` reaches the journal as `msg: [object Object]` and every field is lost. Interpolate instead. Cost a debugging session on 2026-09-23, when a cassette publish that had worked looked like it had done nothing.
 - `bitspire.service` runs as the `lamassu` user; `/var/lib/bitspire` is its `dataDir` (ReadWritePaths). DB lives at `/var/lib/bitspire/state.db` (we previously had `/var/lib/lamassu-atm` — that path is gone on dev, see commit `9c455d6`).
 - The `lightning.lightningPub` field on `LightningServices` is a `LightningBackend` *adapter*, not a `LightningPubClient`. Don't try to call LP-only methods on it.
 
diff --git a/apps/machine/src/services/operator-config.ts b/apps/machine/src/services/operator-config.ts
index 2f33f73..f81b5d5 100644
--- a/apps/machine/src/services/operator-config.ts
+++ b/apps/machine/src/services/operator-config.ts
@@ -147,7 +147,7 @@ export async function startOperatorConfigService(
       },
     }
   )
-  console.log('[OperatorConfig] Subscribed:', { dTag, subscriptionId })
+  console.log(`[OperatorConfig] Subscribed: d=${dTag} sub=${subscriptionId}`)
 
   const heartbeat = setInterval(() => {
     publishCassettesState(cfg, api, machineId).catch((err) =>
@@ -342,6 +342,9 @@ async function publishCassettesState(
 
   await cfg.nostrClient.publish(event)
   await api.markStatePublished(createdAt)
-  console.log('[OperatorConfig] cassettes-state published:', { dTag, eventId: event.id, createdAt })
+  console.log(
+    `[OperatorConfig] cassettes-state published: id=${event.id.slice(0, 12)}… ` +
+      `created_at=${createdAt} seq=${seq} applied_ops=${appliedOps.length} d=${dTag}`
+  )
   return true
 }
diff --git a/apps/machine/src/services/operator-fees.ts b/apps/machine/src/services/operator-fees.ts
index 4e699a3..8afb420 100644
--- a/apps/machine/src/services/operator-fees.ts
+++ b/apps/machine/src/services/operator-fees.ts
@@ -132,7 +132,7 @@ export async function startOperatorFeesService(
       },
     }
   )
-  console.log('[Fees] Subscribed:', { dTag, subscriptionId })
+  console.log(`[Fees] Subscribed: d=${dTag} sub=${subscriptionId}`)
 
   return {
     stop: () => cfg.nostrClient.unsubscribe(subscriptionId),