Companion lost-status response validation

Validated on 2026-10-10. These are production-path host tests, browser tests and firmware builds. No lab radio was flashed for this feature; this report does not qualify a sleeping tracker client or a live LoRa exchange.

Automated checks

The responder test executes the actual private receive callback, message composition/send functions, ACK handling and local CLI policy. Seven compiled variants cover normal and shared one-key DM queues, a text terminal, explicit STM32 enablement, default STM32 exclusion and explicit exclusion elsewhere. AddressSanitizer and UndefinedBehaviorSanitizer checks passed.

Coverage includes exact question matching, Yes/No loop avoidance, known full identities, temporary/unknown contacts, room/channel/CLI exclusions, a full offline inbox, duplicate requests, cooldowns, clock wrap, busy packet/ACK capacity, send failures and preservation of pending user messages/deadlines. Queueing the response preserves the shared send timer. ACK reception retains the existing shared-timer behavior; independent per-message expiry continues to protect pending user deliveries. Excluded builds have no responder state, automatic send, successful setting command, save or WebConfig capability.

Saved preference tests cover all three values, all 256 stored byte values, legacy images loading off, reboot, atomic save failures, recovery copies and runtime adapter preservation. Existing CLI, delivery, inbox, notifications and preference regression suites passed after updating adapters for the new append-only preference byte.

WebConfig tests execute the actual JSON and settings handlers with ArduinoJson. Chromium exercises Off -> No -> Yes -> Off, Companion-only visibility and the absence of the control on infrastructure roles. Existing browser, authorization, secret masking and generated asset checks passed. Both new suites are included in the unit-test workflow.

Capacity and reliability

The responder cache is 184 bytes on ARM and retains four complete public keys. The saved preference uses an existing padding byte in the tested ARM preference object and one new byte in its explicit storage image. No heap allocation is introduced by the responder.

Compact STM32 Companion images exceeded their existing application boundary when the responder was included. Those default to MESH_ENABLE_LOST_REPLY=0, preserving their existing features and filesystem layout. Explicit opt-in is tested synthetically and remains subject to the normal capacity checks.

The ordinary RAK WisMesh Tag BLE queue uses 240 frames, retaining 350 contacts and 40 channels and saving 2,832 bytes. Source comparison showed that its prior 256-frame recipe was already below the current runtime RAM allowance before the new 184-byte responder cache. Full retains its 256-frame shared queue. Sanitized tests exercise real FIFO wrapping, downloads and held-DM isolation at 240 slots, plus the production Full override.

Queueing an answer suppresses that request even if later delivery fails. A tracker needs a fresh timestamp for a later poll, must stay awake for the private answer, and must authenticate its configured Companion. Plain Yes/No answers do not contain a poll ID, so delayed replies cannot be precisely correlated with a newer poll. An unanswered poll means unknown.

Firmware build qualification

All ten final builds passed flash and internal RAM policy checks. Compact STM32 and both Full targets were also packaged using the normal v1.17.1.9-halo-keymind-cascade-dev label. Ordinary targets used their normal PlatformIO recipes. Full nRF52 UF2 boundaries and applicable Bluetooth DFU handoff checks passed. These are local qualification artifacts, not new published release assets.

Companion target	Responder	Flash used / limit (bytes)	Link-time internal RAM available / required (bytes)
RAK 3x72 USB	Excluded	228,924 / 229,376	24,728 / 17,408
Tiny Relay USB	Excluded	228,944 / 229,376	24,728 / 17,408
Wio-E5 Mini USB	Excluded	228,888 / 229,376	24,704 / 17,408
Wio-E5 USB	Excluded	229,008 / 229,376	24,736 / 17,408
T1000-E Full	Included	607,480 / 708,608	87,064 / 44,864
RAK WisMesh Tag Full	Included	649,408 / 712,704	82,112 / 44,864
T1000-E USB	Included	426,756 / 708,608	48,248 / 38,944
Pico W USB	Included	640,180 / 1,568,768	101,712 / 17,408
Heltec V4 BLE	Included	1,550,217 / 6,553,600	263,448 / 118,560
RAK WisMesh Tag BLE	Included	459,564 / 712,704	46,316 / 44,864

The STM32 historical-size table uses byte entries while retaining a 32-bit input file size; exhaustive tests reject oversized aliases and partial images. Tiny Relay and Wio-E5 use the size option already used by neighboring STM32 recipes. Existing terminal help was combined into fewer writes while retaining its text, order and 256-byte maximum per write. Supported images also show the new lost-reply commands. Contacts, channels and filesystem boundaries are unchanged on those compact boards.