The chat screen asked the claw for everything the cache did not hold by counting events, and a session that ran for weeks cost the whole record the first time it opened here. The stream now names each frame's seq and the cache stores it, so a reopening screen sends since=<seq> and receives only the gap. The cache migrates in place: the old count of events is exactly the last seq plus one, because the record numbers densely. A screen with no cache opens on the newest turn and walks back through the new history route when the reader reaches the top, one whole turn per page, so the phone does not hold a weeks-long transcript to show the last few messages. Pages are folded through the same reducer the stream uses and prepended, since the list runs oldest first: appended, they would land at the newest end. A reset comment (the record no longer holds the cursor) drops the mirror, and the tail that follows rebuilds it. The outcome tag colours a steered turn as an accent rather than a failure, matching the web UI.
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Rhema Android
The phone client of the claw (the resident agent daemon): Kotlin + Jetpack Compose, single module, deliberately small. It chats with the agent, reports phone status as events, shows the agent's notifications as system notifications, executes the agent's phone commands (DND, alerts), and manages the device fleet the claw keeps.
What it does
-
Settings: a nav of submenus mirroring the web UI's settings sidebar — the "Phone" group (Status reporting, Devices, Diagnostics) and the "Claw" group (Model providers, Connection), one page per entry behind a back arrow. First launch is the exception: it lands straight on the connection page until a base URL is saved and validated with
GET /healthz. Stores the claw base URL and bearer token (plus a generated, persistent device ID) in app-private DataStore. The Devices page is the Phones card, Status reporting and Model providers their own pages (both described below): the backend instances (GET /v1/providers), each one's live model listing, and the active pair staged as a draft behind an explicit save (PUT /v1/providers/active; it applies from the claw's next turn). Model options carry the listing's vision verdict the way the web and the TUI spell it —◉ visionwhen the adapter knows the model takes images, a bareno visionwhen it knows it does not, nothing when the key is absent (unknown is no verdict, never afalse). The Diagnostics page answers "why is the fleet row stale" from the phone's side: the three WorkManager jobs' live state (an empty info list — a cancelled schedule — is the loud answer), the two clocks (when this phone last landed a full report vs. when the claw last stamped the device; the claw-behind-phone callout is "reporting but not landing", the network-error one is "claw unreachable"), auto-detected system checks (battery optimization, background restriction, notifications) each with a jump into the exact settings page when the setting is wrong, a "report now" kick of the status worker (its one-time job has a row of its own, and every worker crash-lands in the log instead of dying silently), and the workers' in-memory flight recorder (a 200-line ring, newest first, copyable) where every run logs its outcome. Trade-off: the token is stored in plain DataStore rather than EncryptedSharedPreferences;androidx.security:security-cryptois an alpha-quality, unmaintained artifact, and the OS app sandbox already covers the realistic threat (other apps). Backups that could exfiltrate the file are disabled in the manifest (allowBackup=false,dataExtractionRules,fullBackupContent). -
Chat: session list (
GET /v1/sessions, interactive sessions first, the phone's ownphone:*status keys hidden) and one chat screen per session. The applied events persist in a per-session cache (DataStore, the newest 500 events, the seq of the last one as its cursor), so a screen opens on its cached transcript at once and the stream connects with?since=<seq>to receive only the gap instead of replaying the session again; the cache flushes at everyturn_doneand when the screen closes. A screen with no cache opens on the claw's newest turn and walks back throughGET /v1/sessions/{key}/historyas the reader scrolls up, one whole turn per page. While a chat screen is open the app holds one SSE connection (GET /v1/sessions/{key}/events, OkHttp streaming GET with the auth header, hand-parsed frames: blank-line delimiteddata:lines with the event's seq on theid:line,:comment keep-alives skipped, the claw'sresetcomment dropping the mirror, unknown event types skipped). The reader's own messages render as right-anchored bubbles (elevated surface, accent bar on the trailing edge); the agent's turns keep the avatar on the left. The composer's (+) door stages images for the next send — a photo-picker pick or a camera shot written straight into a FileProvider-mapped cache uri (no CAMERA permission) — each a removable▣N name sizechip with a downscaled thumbnail above the input row. The claw's own budget is enforced client-side with visible inline errors, never silent drops: at most eight images a message, 5 MiB decoded each, png/jpeg/gif/webp only (a heic pick refuses rather than being sent), and the text stays required — the claw 422s an empty text even with images aboard. Send reads the staged files back and POSTs bare base64 in the body'simages(omitted when there are none, so the old{"text"}shape stays byte-stable); a failed send restores the draft and the chips. The composer POSTs{"text"}plus those images; the claw's documented dance is preserved: subscribe first, then POST, the reply arrives on the stream. Thinking deltas render dim and collapsible, tool rows show name/summary with error coloring (bash-like tools render as shell lines instead: dim$prefix, the command line, and an exit-code badge), pasted payloads embedded in a message as pairedU+FFFCmarks render as compact▣N 5Lchips, andattachmentevents render as cards: file name, size, caption, an inline preview for small (≤ 2 MB) images, and a download-and-open row (bytes fromGET /v1/attachments/{id}land in the app cache and open through a FileProviderACTION_VIEW, the only way another app can read a private cache file). Sent messages with images render their thumbnails in the right-anchored bubble: the optimistic row previews the staged files at once, and a replayeduser_message(the stream carries attachment ids, never bytes) fetches through the same bearer-guardedGET /v1/attachments/{id}as an attachment card, decoded downscaled and capped at the card's 240 dp. The stream's echo of a message this surface just sent dedupes against the optimistic row (same text, same image count), so the local previews stand. The agent'sconsent_requestquestions (a secret, or an approval of a phone control action) render as cards answered in place —POST/DELETE /v1/consents/{id}— andconsent_resolvedsettles them (a reconnect's replay rebuilds the settled states). The streaming reply is finalized byturn_done. The chat renders the claw's presentation identity (GET /v1/agent, cached in DataStore, refreshed per app open and on the session list's refresh): the avatar image when one is set (GET /v1/agent/avatar), else the initials, the name's first letter, or R; the agent's name labels every turn, falling back to "rhema". Replies render as markdown (com.mikepenz:multiplatform-markdown-renderer, GFM flavour: raw HTML stays literal, so model output never mounts as markup; the streaming cursor rides the source text). The transcript is a reversed LazyColumn: the newest turn anchors to the bottom edge, so streamed blocks stay on screen and a reader scrolled into history is not yanked back. -
Phone status source: a WorkManager periodic worker (15 min, the OS floor,
NetworkType.CONNECTED) reads every sensor into one snapshot and POSTs only transitions vs the last successfully-posted snapshot (persisted in DataStore) toPOST /v1/ingest. Each sensor has its own transition rule, tuned to what would otherwise spam:Topic Posts when Needs batterycharging flip, or decile bucket change ( level/10)nothing networkwifi/metered/offlinechangesnothing dndon/off changes nothing locationmoved 300 m or more since the last posted fix location permission appthe foreground package changes usage access grant devicethe identity fingerprint changes (basically once, and on app or OS updates) nothing wifithe connected SSID changes location permission alarmthe next alarm moves nothing heartbeatalways, when a run produced no other post nothing A sensor that is ungranted or unreadable produces no posts for its topic, never an error. Rich readings carry their own honesty: a location payload includes accuracy and fix age, the app payload the package, its label and how long it has been current. The location read requests a fresh fix (fused on API 31+, else gps then network) with a 20 s ceiling and falls back to the newest last-known fix under 30 min; a plain last-known read would answer with whatever another app left cached, which on a stationary phone is where the phone was, not where it is. The heartbeat exists for the fleet's last-seen time: the claw stamps a device "seen" on whatever post lands, so a run with no transitions posts one anyway and the row stays fresh at the worker's cadence instead of the last flip. A failed post ends the run anyway — the snapshot is only saved when every post landed, so the next scheduled run re-derives the whole transition set;
retry()would hand the cadence to WorkManager's exponential backoff (hours) and the phone would read as gone. And because idle devices defer periodic work (Doze stretches the fifteen-minute floor to hours), the app kicks a status run on every foreground: a phone in hand reports then and there, and the fleet card reloads on each landed run (lastReportAt) so its own row reads from the new clock instead of the one it was opened at.Every report is an observation on the claw: it lands in the phone tables (the ingest answers
{"ingested": "observed"}) and aphonetool status question reads it. No report dispatches a turn, so a commute or a session of app-hopping is never a model call per move, and a battery flip never becomes a push notification.Charging flips additionally kick a one-shot worker from a process-lifetime broadcast receiver (
ACTION_POWER_CONNECTED|DISCONNECTED,ACTION_BATTERY_CHANGED). Manifest registration for those actions is refused by the OS (implicit broadcasts, API 26+), so the receiver is registered dynamically in the Application and stays dumb: it only enqueues work. -
Phone fleet: the Settings screen's Phones card is the management surface over the claw's registry (
GET /v1/phones), not a private view: every device the claw has heard from, its self-reported label (thedevicetopic's manufacturer and model), its last-seen time, and a one-line state. This install's row is marked; every other row carries Forget, whichDELETEs the device's records on the claw after a confirm dialog. A device id lives for one install, so a reinstall or a cleared app data leaves the old identity behind as a stale row with an old last-seen time; that row is what Forget is for. A forgotten phone that still reports re-registers on its next run. The Status reporting card names what this phone cannot send until a grant is flipped (location permission, usage access, DND access) and walks to the system toggles; the rows re-read on every ON_RESUME. -
Phone commands: a third periodic worker polls
GET /v1/phone/commands?device=<id>— the agent's consented control queue — every 15 minutes like the other workers (that interval is the control latency; opening the app kicks a one-shot KEEP-coalesced run, so the queue is fresh while the phone is in hand). Commands execute in order, each answered withPOST /v1/phone/commands/{id}/result, which doubles as the ack: a failed post leaves the command queued and the next run repeats it.dnd_on/dnd_offset the interruption filter; they need the special Do Not Disturb access grant (Settings → Special app access — a settings toggle, not a permission), and without it the worker reports that back and toggles nothing.alertposts a heads-up, sound-on notification on the high-importancerhema-alertchannel with the args'title/body(falling back to "claw" / the action name). Unknown actions are reported, never guessed. -
Notifications: a second periodic worker polls
GET /v1/notifications?device=<id>&since=<cursor>(cursor in DataStore), posts each as a system notification on channelrhema(tap opens the app; the API carries no session key, so it lands on the session list), thenPOSTs an ack per id. Acks are best-effort: the cursor means "seen", not "acked", so a failed ack does not re-notify. -
Permissions:
INTERNET,POST_NOTIFICATIONS(runtime request on API 33+, re-asked per cold start; the OS throttles denials),RECEIVE_BOOT_COMPLETED(boot receiver re-runs the idempotent KEEP schedule; WorkManager also re-enqueues its own work),ACCESS_COARSE_LOCATION/ACCESS_FINE_LOCATION(runtime request per cold start like notifications; a refusal only silences thelocationandwifitopics). Two grants are settings toggles, not permissions: usage access (PACKAGE_USAGE_STATSis declared only so the toggle can grant it) for theapptopic, and Do Not Disturb access (ACCESS_NOTIFICATION_POLICY, declared only so the app appears on the "Do Not Disturb access" screen's list — an undeclared app opens that screen and finds nothing to flip) for the dnd commands. The Status reporting page in Settings shows all three.
API contract (the claw's /v1)
All under one base URL; Authorization: Bearer <token> on /v1, never on
/healthz.
| Endpoint | Used for |
|---|---|
GET /healthz |
settings gate (no auth) |
GET /v1/providers |
backend instances + active pair |
GET /v1/providers/{id}/models |
an instance's live model listing |
PUT /v1/providers/active |
switch the backend instance, persisted |
GET /v1/sessions |
session list |
POST /v1/sessions/{key}/messages |
{"text"}, optional images (≤ 8, ≤ 5 MiB decoded each, bare base64) → 202; reply via stream |
GET /v1/sessions/{key}/events |
SSE, replay-then-live: user_message, thinking_delta, text_delta, tool_start, tool_result, turn_done, attachment, consent_request, consent_resolved. Every frame carries the record's seq on its id: line; ?since=<seq> replays only the events past it, and no cursor replays the newest turn only — the transcript cache's cursor |
GET /v1/sessions/{key}/history?before=&limit= |
one page of whole turns older than before, ending exactly there, with more saying whether anything precedes it — the chat screen's walk back |
GET /v1/attachments/{id} |
an attachment event's bytes (bearer) |
GET /v1/consents |
pending consent questions, oldest first |
POST /v1/consents/{id} |
answer one: {"secret"} or {"grant"} |
DELETE /v1/consents/{id} |
deny / cancel a question |
GET /v1/phones |
the device fleet, labels and topics included |
DELETE /v1/phones/{device} |
retire a device's records |
GET /v1/phone/commands?device= |
the control queue for this device |
POST /v1/phone/commands/{id}/result |
execution result; doubles as the ack |
POST /v1/ingest |
{"source","key","payload"} |
GET /v1/notifications?device=&since= |
ascending notification list |
POST /v1/notifications/{id}/ack |
best-effort ack |
Ingest payloads emitted
source is always "phone", key is phone:<deviceId>:<topic>.
Every report is an observation on the claw: it feeds the status the
phone tool reads, and no turn is run (the ingest answers
{"ingested": "observed"}):
{"topic": "battery", "value": "83", "charging": true}
{"topic": "battery", "value": "17", "charging": false}
{"topic": "network", "value": "wifi"} // or "metered" | "offline"
{"topic": "dnd", "value": "on"} // or "off"
{"topic": "location", "lat": 48.85, "lon": 2.35, "accuracy_m": 12.0, "provider": "fused", "age_s": 45}
{"topic": "app", "value": "com.google.android.maps", "label": "Maps", "age_s": 900}
{"topic": "device", "value": "Google Pixel 9", "manufacturer": "Google", "model": "Pixel 9", "android": "16", "sdk": 36, "app_version": "0.1.0"}
{"topic": "wifi", "value": "home"}
{"topic": "alarm", "value": 1760000000000, "in_min": 542}
{"topic": "heartbeat", "ts": 1760000000000}
battery.value is the raw level; the transition rule is charging-flip or
decile bucket change. location posts on a 300 m move from the last posted
fix. app excludes this app itself. wifi needs the location grant
(Android treats an SSID read as location) and is skipped when the system
answers with a placeholder. Unreadable or ungranted sensors produce no
posts for that topic.
Trade-offs
- Notification latency: no push infrastructure; background notifications are as fresh as the WorkManager interval (15 min). The chat screen is always live via SSE.
- Transcript cache: the applied event log persists per session (the
newest 500 events plus their seqs), so a screen opens on its cached
transcript and the stream resumes past it. The cache is a cursor over
the claw's record, not a copy of it: a claw database wiped behind the
phone's back leaves the cache pointing past a history that no longer
exists, which the claw answers with a
resetcomment and the newest turn — the screen drops its stale rows and rebuilds from those. - Older turns are fetched, not cached: the screen holds the cached window plus whatever the reader scrolled back to; reopening a session starts from the cache again, and the walk back re-reads the record. Nothing older is persisted, so the cache stays a fixed size.
- First launch: nothing works until Settings validates
/healthz.
One-consumer principle
The claw's /v1 is the contract. The app has no private endpoints and no
special privileges; every need goes through the same public API any other
client sees. If a feature seems to need a claw change, that change belongs
in the claw's public API first.
Build
Requirements: JDK 17+ (Gradle 9.3.1 runs up to the current JDK; the system
default is fine), Android SDK with platform android-36 (set ANDROID_HOME
or local.properties sdk.dir).
ANDROID_HOME=~/Android/Sdk ./gradlew :app:assembleDebug # debug APK
ANDROID_HOME=~/Android/Sdk ./gradlew :app:lintDebug # lint
ANDROID_HOME=~/Android/Sdk ./gradlew :app:assembleRelease # release APK
APK lands at app/build/outputs/apk/debug/app-debug.apk. Install and run:
adb install app/build/outputs/apk/debug/app-debug.apk
Debug builds are signed with the committed debug.keystore (the standard
Android Debug identity: store/key password android, alias
androiddebugkey), so any build installs over any other: a CI artifact
updates a locally-built install and vice versa. The key is deliberately
not a secret — debug keys guard nothing — a stable signature across
machines is the whole point. The build never touches
~/.android/debug.keystore, so other projects keep their own key.
Release builds are the opposite custody model: the key anchors the
future edge channel — whatever it signs can silently update an install
that trusts the channel — so it never travels with the source. CI holds
it as two repository secrets (ANDROID_RELEASE_KEYSTORE, the base64
keystore, and ANDROID_RELEASE_KEYSTORE_PASSWORD; alias
rhema-release), and the android workflow pins both certificates by
SHA-256 fingerprint before uploading an artifact. Locally, blank
environment leaves assembleRelease unsigned: a build check, never a
deliverable.
Pinned toolchain: Gradle 9.3.1 (wrapper), AGP 8.13.2, Kotlin 2.2.21
(org.jetbrains.kotlin.plugin.compose + plugin.serialization), Compose
BOM 2025.12.01, minSdk 26 / target & compileSdk 36.
Layout
app/src/main/java/rs/rhema/phone/
MainActivity.kt nav state + POST_NOTIFICATIONS runtime request
RhemaApp.kt Application: container, channel, schedule, receiver
di/AppContainer.kt manual DI (OkHttp, Json, repos, api, notifier)
data/ DataStore-backed settings + status repositories
sensors/ the status readers (location, foreground app, wifi, alarm, identity)
net/ ClawApi (one object per endpoint, sealed result type)
chat/ChatController transcript state + SSE loop for the open screen
ui/ Theme, shared design components, SettingsScreen,
SessionsScreen, ChatScreen
work/ PhoneStatusWorker, NotificationsWorker,
PhoneCommandWorker, receivers, scheduling
notif/Notifier.kt channel + system notifications
Cleartext and certificates
The claw is self-hosted, so its address is whatever the operator points
at: a LAN name (kosmos.lan), a bare IP, a Tailscale name, where a
publicly-trusted certificate is rare. The app therefore permits
cleartext HTTP app-wide and trusts user-installed CAs (mkcert installs
into the user store, so a mkcert-secured claw works over HTTPS too).
Only the operator's configured claw is ever contacted, and the bearer
token is the auth; prefer HTTPS wherever the deployment has a real
certificate.
Road notes
- Theming is Jadeite dark, always, the same tokens as the TUI and the
web UI (
crates/rhema-code/src/palette.rsDARK). No light scheme, no dynamic color: the palette is the brand. The screens mirror the web claw's redesign: cards with hairline-divided rows, state dots, badges, toned callouts, avatar-row transcripts with accent-bar tool cards, and the round accent send button; the shared pieces live inui/Components.kt, the Compose counterparts of the web's components. - Future onboarding: scanning a QR code from the claw (base URL + token, rendered by the web UI or printed in the terminal) instead of typing both by hand. Deliberately deferred; the Settings screen is the manual path today.
- Distribution: the CI release artifact (
rhema-android-release) is the future edge channel's payload — publishing it somewhere public (a Gitea generic package, an always-latest link) is deferred; the secret release key is already the channel's trust anchor, so the artifact is worth building and pinning now.