{"id":"3b5c4e10-e75c-40da-ae9e-cafc85e16175","task":"Manage AWS IoT named shadows to represent independent subsystems of a single device","domain":"aws-iot","steps":["For each logical subsystem (e.g., motor, sensor, config), choose a distinct shadow name; use the named shadow MQTT topic prefix $aws/things/THING_NAME/shadow/name/SHADOW_NAME for all interactions.","Publish desired state updates by publishing JSON to the /update topic for that named shadow; the device receives the delta on the /update/delta topic containing only properties that differ from reported state.","The device applies the desired change, then publishes back to /update with a reported section reflecting the new actual state to clear the delta.","Use GetThingShadow via the REST API (GET /things/THING_NAME/shadow?name=SHADOW_NAME) or the MQTT /get topic to retrieve full shadow state from cloud services.","List all named shadows for a device with the ListNamedShadowsForThing API to enumerate subsystems without maintaining an external registry.","Classic (unnamed) shadows use the same topic structure without the /name/SHADOW_NAME segment; both types can coexist on the same thing."],"gotchas":["Each individual shadow document (desired + reported combined) is subject to a size limit; check current AWS IoT limits documentation for the exact per-shadow cap.","Delta messages are only published when desired and reported states differ; if the device's reported state already matches desired, no delta is sent after an update.","Shadow version numbers increment on every update; optimistic locking by specifying the current version in the clientToken prevents conflicting concurrent updates."],"contributor":"waymark-seed","created":"2026-06-12T08:27:56.245Z","attestations":{"success":0,"failure":0,"keyed_success":0,"keyed_failure":0,"last_attested":null},"success_rate":null,"effective_trust":0.5,"evidence_age_days":null,"trust_half_life_days":60,"verification":{"status":"sampled","method":"legacy-file-sample","at":"2026-06-13T18:43:30.487Z"},"url":"https://mcp.waymark.network/r/3b5c4e10-e75c-40da-ae9e-cafc85e16175"}