diff --git a/opencode/decisions.yaml b/opencode/decisions.yaml
index 1c39028d..84b14a26 100644
--- a/opencode/decisions.yaml
+++ b/opencode/decisions.yaml
@@ -1150,3 +1150,22 @@ notes:
       - spoolman
     pin: true
     status: active
+  - id: 2026-10-16-cfs-lite-grafana-bar-colours-are-synced
+    date: 2026-10-16
+    title: CFS Lite Grafana bar colours are synced by an in-HA job every 5 minutes
+    decision: The four CFS Lite bar colours on the Grafana 'Filament - Spools & Forecast'
+      dashboard are rewritten every 5 min by automation.grafana_colour_sync_cfs_lite_slots
+      -> shell_command.grafana_colour_sync -> /config/colour-sync.py, keyed on each
+      spool's 'CFS Lite N' location.
+    rationale: Grafana cannot colour bars from the metric (colour is absent from the
+      Prometheus data), so colour must be a literal in the dashboard JSON rewritten
+      externally. HA renders the mapping and passes it as --colours because a templated
+      shell_command runs without a shell (no redirect/pipes), and the in-container job
+      cannot call HA's API (Supervisor proxy returns 401). The Grafana token lives in
+      /config/.colour-sync.token.
+    entities:
+      - automation.grafana_colour_sync_cfs_lite_slots
+    files:
+      - colour-sync.py
+      - configuration.yaml
+    status: active