Files
ai-app/PLAN.md
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irisandClaude Fable 5 56491f84b0 Follow the sibling project's rename to dev-updater
It is no longer "local" -- it serves over WireGuard rather than the LAN --
and it is specifically for developing new apps. Renaming the references
here at the same time keeps one name to search for across both repos.

Also drops the last references to gen-dev-cert.sh, which the in-process
certificate generation replaced: the build script and the Gradle task now
say to start the server once, and test-wg-tunnel.sh reads the
certificates from the XDG directory rather than the repo.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_017xn8nHw1tw1R6PtiY1eEtw
2026-08-25 05:10:20 -04:00

31 KiB

ai-app — plan

A phone interface to AI coding sessions — Claude Code and llama.cpp for now — built to replace the Claude app for day-to-day use. Two motivations: local models need a front end at all, and owning the client means fixing the things the official app gets wrong (e.g. it won't deliver a typed message until the session fully finishes its turn, where the TUI injects it at the next tool boundary).

Same shape as ../dev-updater: a Rust (Axum) backend on the desktop, a Kotlin/Compose Android app, pinned self-signed TLS between them.

The one idea everything hangs off

Both session types are a child process speaking JSONL over stdio:

  • Claude Code: claude -p --input-format stream-json --output-format stream-json — bidirectional streaming JSON. User messages sent while a turn is running are injected at the next opportunity (the TUI behavior we want), a control protocol carries interrupts and permission requests, --resume <id> picks a session back up after a backend restart.
  • llama.cpp: pi in RPC mode (pi --mode rpc), pointed at a llama-server endpoint. Same deal: JSONL on stdio, prompt (with images), steer for mid-run injection, abort, set_model, compact / set_auto_compaction, session files that survive restarts, structured events for streaming text and tool executions.

So the backend has one abstraction — spawn a process, translate its dialect to a common event stream, keep an append-only transcript — and two translators. SSH support falls out of the same shape: a remote session is the identical command run as ssh <host> <cmd>; stdio doesn't care.

Decisions already made (2026-08-24):

  • llama.cpp harness: pi RPC now, with the session abstraction kept clean enough that a custom Rust agent loop can be added as a third driver later.
  • The backend manages llama-server itself (start with a chosen GGUF, stop, swap models), locally and over SSH.
  • Claude permission prompts are interactive in the app, with a per-session permission mode chosen at spawn.
  • One backend on the main machine; the phone talks only to it, and it reaches other hosts via SSH. Remote hosts need the CLIs installed but no backend.

Architecture

Providers and hosts (decided 2026-08-25)

Two independent axes, configured separately and chosen per session:

  • A provider is what runs: a driver kind, the command to invoke, and the models worth offering. claude-cli is the first — named for the CLI specifically, since bare "claude" would suggest the credit-billed API, which this is not. llama.cpp becomes a second provider later.
  • A host is where it runs: an ssh target. Absent means the backend machine itself.

Sessions name both. Keeping them independent is what the motivating setup requires: the backend runs on the machine the phone can reach (where WireGuard terminates), which is not necessarily where a CLI is installed — here the Claude CLI lives only in a VM on that machine, while llama.cpp will be on the host itself. Pinning a host into a provider would make "the Claude CLI" and "the Claude CLI over there" two things to configure and choose between, and would stop the same provider from being sent somewhere else for one session.

Android app (Compose)
   │  HTTPS (pinned CA) — REST for actions, SSE for live events
   ▼
backend (Rust/Axum, desktop)
   ├─ SessionManager ── Session ── Driver (trait)
   │                      ├─ ClaudeDriver   (claude stream-json)
   │                      └─ PiDriver       (pi --mode rpc)
   │        each driver's process is spawned locally or as `ssh host …`,
   │        decided per session by the host it names
   ├─ LlamaServerManager  (llama-server lifecycle, local + SSH)
   ├─ UsageMonitor        (Anthropic OAuth usage endpoint)
   └─ config.json + per-session transcript files

Backend layout (server/)

Mirroring dev-updater's stack: axum 0.8, axum-server + rustls, tokio, serde, clap, tracing. Rust edition 2024, warning-clean, clippy in CI habit.

  • main.rs — bootstrap, TLS listener.
  • routes.rs — the whole HTTP table in one module doc comment (as in dev-updater).
  • session/mod.rsSessionManager: the live session registry, every mutation funnels through it (the registry.rs pattern: in-memory and on-disk state can't come apart).
  • session/driver.rs — the Driver trait and the common event model.
  • session/claude.rs, session/pi.rs — the two translators.
  • session/transcript.rs — append-only JSONL event log per session, with monotonically increasing sequence numbers (the phone's resume cursor).
  • llama.rsLlamaServerManager.
  • hosts.rs — host configs and the ssh command builder.
  • usage.rs — Anthropic usage polling.
  • config.rs — persisted schema.

The common event model

Driver output, whatever the dialect, is normalized into one event enum before it touches the transcript or the phone:

  • UserMessage { text } — what the user sent, echoed into the transcript by the manager (not by drivers) so every device renders the conversation from the one stream. (Added 2026-08-24 during phase 1: without it, reconnects and second devices would lose the user's side.)
  • AssistantText { delta } — streaming text (rendered as markdown).
  • ToolStart / ToolUpdate / ToolEnd { tool, input, output } — the "view tools it's running" screen is just these.
  • Image { ref } — images in output (screenshots from tools, etc.) are saved under the session dir and referenced by id; the phone fetches them by URL.
  • Question { id, prompt, options } — anything the session needs a human for: Claude's AskUserQuestion, and permission requests (canUseTool) are the same shape with approve/deny options. Answered via one endpoint.
  • Answered { id, answer } — the manager's record of a question being answered, so a rendered question card resolves on every connected device, not just the one that answered (added 2026-08-24, same reasoning as UserMessage).
  • Status { state } — idle / running / awaiting-input / compacting / exited.
  • UsageDelta { tokens } — per-turn token counts where the dialect reports them (both do).
  • Error { message }.

Every event is appended to the session's transcript file with a sequence number, then fanned out to any connected SSE subscribers. The phone renders purely from this stream: reconnecting means "give me events after seq N" — no separate "load history" path to drift from the live one.

Inbound, the driver trait is small:

trait Driver {
    fn send_user_message(&self, text: String, images: Vec<ImageRef>);
    fn answer_question(&self, id: QuestionId, answer: Answer);
    fn interrupt(&self);                       // stop mid-run, session survives
    fn set_model(&self, model: &str);
    fn compact(&self);                         // pi: native; claude: /compact
    fn shutdown(&self);                        // graceful process exit
}

send_user_message during a run is the point of the whole app: both dialects queue it for injection at the next tool boundary rather than the end of the turn. Claude's dialect: a user message on stdin mid-stream; pi's: steer.

Claude driver specifics

  • Spawn: claude -p --verbose --input-format stream-json --output-format stream-json --permission-mode <mode> in the chosen working directory, plus --model at spawn. Permission mode (default/plan/acceptEdits/ bypassPermissions) is chosen on the spawn screen.
  • Interactive permissions: run with the stream-json control protocol's permission request flow (the same mechanism the Agent SDK's canUseTool uses) so tool approvals arrive as control requests, become Question events, and our answer goes back as the control response. Verify the exact control-request wire format against the current CLI early in implementation — it's the least-documented part of this plan.
  • Interrupt: control-protocol interrupt request.
  • Model change mid-session: try the control protocol's set-model; if the installed CLI doesn't support it, fall back to shutdown + respawn with --resume <session_id> --model <new> — cheap, since Claude persists sessions in ~/.claude/projects anyway. That same resume path is the crash recovery story: a dead backend or a killed process loses nothing.
  • Images in: base64 image content blocks in the stream-json user message.
  • Working directory, host, and model are spawn-screen fields.

pi driver specifics

  • Spawn: pi --mode rpc --provider openai-generic --model <name> (endpoint = the llama-server the LlamaServerManager provides), --session-dir under our session storage so transcripts and pi's own session files live together.
  • Auto-compaction on by default (set_auto_compaction), threshold configurable per session; manual compact exposed as a button.
  • steer for mid-run messages, abort for stop, set_model when the target endpoint changes.
  • pi's session JSONL gives resume-after-restart, same as Claude's.

llama-server management

config.json lists models (name → GGUF path or llama-server args, per host) and hosts. The manager runs at most one llama-server per (host, model), spawned on demand when a session needs it:

  • Spawn (local or ssh host llama-server …) on an allocated port, wait on /health, hand the endpoint to the pi driver.
  • Refcounted by sessions. The path out, written in the same change as the spawn: the last session using an instance releasing it starts an idle timer (configurable, e.g. 10 min), after which it's killed. Delete of the last session kills it immediately.
  • "Change model" on a llama session = acquire the new model's server, set_model on pi, release the old one. Context carries over (it's prompt-replayed by pi against the new endpoint).
  • Remote llama-server output is only reachable from the backend host, and binds localhost on the remote side with an SSH local port forward (ssh -L) held by the manager — no LAN-exposed inference ports.

SSH

  • Host entries in config.json: name, user@host, optional ssh options, which capabilities it has (claude / pi / llama-server, with paths if not on PATH). Key-based auth only, using the system ssh client via tokio::process — no Rust SSH library; this inherits ~/.ssh/config, agents, and jump hosts for free. (Rule 23: openssh is already here and battle-tested; a library buys nothing but a second config surface.)
  • A remote session is exactly a local one with the command wrapped in ssh -T host …. Process death ≙ connection death; the session shows as exited and both dialects resume (--resume / pi session file) on respawn, so a dropped SSH connection is an annoyance, not data loss.
  • Images and attachments for remote sessions are written to the remote session dir via scp/stdin before the message referencing them is sent.

Usage limits (Claude)

Poll https://api.anthropic.com/api/oauth/usage — the same endpoint behind Claude Code's /usage — with the OAuth access token from Claude Code's local credential store (~/.claude/.credentials.json), headers anthropic-beta: oauth-2025-04-20 and User-Agent: claude-code/<version> (without the User-Agent it lands in an aggressively rate-limited bucket). Poll at ≥180 s, only while any Claude session exists or the usage screen is open, cache the last answer. Surface: 5-hour and weekly window utilization % and reset times. It's undocumented, so usage.rs treats every field as optional and degrades to "unavailable" rather than erroring. Structure it as one UsageProvider per paid service so a second service later is a new impl, not a parallel screen (rule 9).

HTTP surface (phone ⇄ backend)

REST for actions, one SSE stream per open session screen for events, all over the pinned TLS listener. SSE over WebSocket because resume-by-cursor (Last-Event-ID = transcript seq) is native to it and the inbound direction is plain POSTs anyway.

GET  /providers                       what can be spawned (name, kind, models)
GET  /hosts                           machines a session can be run on
GET  /sessions                        list (id, provider, host, title, model, status, last activity)
POST /sessions                        spawn {provider, host, model, cwd, permission_mode, title}
GET  /sessions/:id/events?after=N     SSE: transcript replay from N, then live
POST /sessions/:id/message            {text, attachment_ids}
POST /sessions/:id/answer             {question_id, answer}   (questions and permissions)
POST /sessions/:id/interrupt
POST /sessions/:id/model              {model}
POST /sessions/:id/compact            (llama sessions)
POST /sessions/:id/attachments        multipart upload → id (referenced by /message)
GET  /sessions/:id/files/:ref         images the session produced or was sent
DELETE /sessions/:id                  kill process, release llama-server, delete transcript+files
GET  /usage                           cached usage windows
GET/PUT /hosts, /models               config editing from the phone

Sessions live in config.json ($XDG_CONFIG_HOME/ai-app/) + a per-session directory under $XDG_DATA_HOME/ai-app/sessions/ (transcript.jsonl, attachments, produced images), owner-only. Deleting a session is the complete path out of everything spawning one created.

Security

  • TLS with a self-signed CA, pinned in the app — same idempotent-CA/reissued-leaf scheme as dev-updater, same one-way-door caveat about regenerating the CA, but generated in process on first start (certs.rs) rather than by a shell script calling openssl (2026-08-25). One place then decides the extensions, the file modes, and which addresses the leaf covers — every local IPv4 plus loopback and the emulator's host alias, so nobody maintains a hardcoded IP — and there is no setup step to forget.
    • Unlike dev-updater, the pinned CA is not a constant in the source: the build reads $XDG_CONFIG_HOME/ai-app/certs/ca.pem from the machine doing the build and generates the constant (generatePinnedCert in app/androidApp/build.gradle.kts; AI_APP_CA overrides). Decided 2026-08-25, and it does three things at once — the trust anchor follows the build machine, so an APK built on the backend host pins that host and one built in the dev VM pins the VM's throwaway CA and is only good for its emulator; there is no second anchor to add for development and forget to remove; and regenerating a CA needs a rebuild rather than a paste, so a stale constant can't quietly disagree with the server.
  • The dev VM is untrusted (decided 2026-08-25): a machine that isn't malicious but could become so. It matters because the repo is a read-write virtiofs mount shared between the VM and the backend host, so under this model everything in it — source, server/target/ binaries, and the shell scripts the host runs, some with sudo — is attacker-writable. Two consequences:
    • Nothing secret lives in the repo. Certificates are generated on the machine that serves them and written to $XDG_CONFIG_HOME/ai-app/certs (0700, keys 0600); config.json and session transcripts go to the XDG config and data directories, per machine. A CA private key the VM could read would let it mint a leaf the pinned app accepts, which is precisely the attack pinning exists to stop — pinning against a CA the attacker holds is no pinning at all. Transcripts move for a plainer reason: they are whole conversations. As a bonus this ends the host and VM sharing one config, which had already produced a test token live on the backend, and takes state out of reach of git clean -xdf.
    • The host should not execute what the VM can write — build and run the backend from a host-only checkout rather than the shared mount. Moving the keys closes the smaller door; this is the larger one.
    • Development in the VM generates its own throwaway CA. Whatever is installed on the real phone must pin only the host's.
    • The CA key is not needed by the server at all (only leaf.pem and leaf-key.pem are read), so it can move offline once the setup is stable; reissuing a leaf is the only time it is wanted.
    • Not addressed, and accepted: a compromised VM can return anything it likes from the sessions it runs, since running an agent there is the point. The blast radius is that session's content, not the backend.
  • This server is strictly more dangerous than the updater: its API is remote code execution (spawn a bypass-permissions Claude on any SSH host). Pinning authenticates the server to the phone but not the phone to the server, so a bearer token adds the other direction. Threat model: the token gates LAN-reachable RCE; it does not (and cannot) defend a compromised backend host or phone — those are inside the trust boundary, and a compromised phone is handled by rotation.
    • Generation: 256 bits from the OS CSPRNG on first run, base64url. A machine credential, never typed twice, so unguessable costs nothing; at this entropy no key stretching is needed.
    • Enrollment: printed once as a terminal QR code (qrcode crate, ANSI), encoding aiapp://enroll?host=…&port=…&token=…. The CA stays embedded in the APK (PinnedCert.kt pattern), so the QR carries no trust material — photographing the terminal leaks only the token (rotatable), never a way to weaken pinning. The app side needs no QR library at all: it registers an intent filter for the aiapp://enroll scheme, and the stock camera app hands the scanned URI straight to MainActivity (2026-08-24).
    • Storage: server keeps only the SHA-256 in config.json (plain hash is enough for high-entropy random input; buys that a leaked config doesn't leak the credential). No "show token again" — lost means rotate. Phone side: sealed with an Android Keystore AES-GCM key (a small hand-rolled helper in ServerConfig.kt — Jetpack's EncryptedSharedPreferences is deprecated with no drop-in successor, and Google's guidance is now "use Keystore directly"; 2026-08-24).
    • Transport: Authorization: Bearer header on every request including the SSE GET. Never a query parameter (URLs leak into logs). The tracing layer must not log the header — covered by a test so a logging change can't silently start leaking it.
    • Verification: one middleware wrapping the entire router in main.rs, never per-route, so a new route can't forget auth. Zero unauthenticated endpoints, /health included. Hash-then-constant-time-compare (subtle); failures logged with peer address plus a small fixed delay — not against brute force (infeasible at 256 bits) but so scanners show up in the log.
    • Rotation (the path out): --rotate-token regenerates, invalidates the old hash immediately, reprints the QR. That's the whole lost-phone story. Config stores a list of {name, hash} (of one, today) so per-device tokens with individual revocation are a config entry later, not a schema migration.
    • Why not mTLS: stronger in theory (key never leaves the Keystore, no bearer secret to exfiltrate), but given pinning the delta is only "someone reads the token off a device already inside the trust boundary", and it costs Android client-cert provisioning ceremony and a worse new-phone story than a QR scan. Revisit if this outgrows single-user-on-LAN.
  • Off-network access: plain WireGuard (decided 2026-08-24; no third party). The backend binds to the WireGuard interface (wg0) only; the phone runs the official WireGuard app (always-on VPN, per-app tunneling), enrolled by scanning its config as a terminal QR (qrencode -t ansiutf8 < phone.conf — same gesture as token enrollment). The only internet-visible thing is one forwarded UDP port that is silent to unauthenticated packets — scanners see it as closed — so the app's pre-auth surface (rustls handshake, hyper parsing, auth middleware) is reachable only from enrolled peers, and the token becomes defense in depth rather than the sole gate. Addressing stays single-path: the phone reaches the backend at its WireGuard address (e.g. 10.66.0.1) from everywhere — one address in the app, one SAN in the leaf cert (SERVER_IP=/SAN override in the cert script), no home/away distinction. Another machine later is one keypair + one [Peer] block.
    • Operational needs, accepted: a public endpoint hostname. The home IP is mostly static but not guaranteed, so the phone's endpoint is a DDNS name (free, e.g. DuckDNS, or the router's built-in client; a curl cron on the backend host works too) that tracks changes automatically. One WireGuard nuance: the phone app resolves the endpoint hostname when the tunnel comes up and does not re-resolve on its own, so on the rare IP change the fix is toggling the tunnel off/on once DDNS has caught up (minutes). The symptom is obvious (app can't reach the backend) and lossless — the SSE cursor design means reconnects replay whatever was missed. Also: at-home traffic rides NAT hairpinning on the router (verify early; most support it, and the fallback is toggling the tunnel off at home).
    • Rejected: Tailscale — same WireGuard underneath with easier setup (no port forward, LAN peer discovery), but it adds a third-party coordination service and account this setup doesn't need at two or three devices; Headscale — self-hosting that coordination server is strictly more moving parts than one wg config per peer at this scale; forwarding the HTTPS port directly — puts every internet scanner one pre-auth bug away from RCE on a machine holding SSH keys.
    • The server still refuses to start without TLS — no plaintext listener exists even inside the tunnel, so the token can't travel unencrypted by misconfiguration, and interface binding failing closed (refuse to start if wg0 is absent, rather than falling back to 0.0.0.0) is part of the same guarantee. Development gets --bind <ip> as an explicit, logged override (loopback for curl, a LAN address for a pre-WireGuard phone) — a deliberate flag, never a fallback, so the fail-closed default is untouched (2026-08-24).
  • The bootstrap-over-HTTP trick from the updater is unnecessary here — the app installs via Dev Updater.

App (app/)

Kotlin + Compose Multiplatform, single :androidApp module, same versions as dev-updater (Kotlin 2.4.x, CMP 1.11.x, JDK 21). Screens:

  1. Session list — cards: kind icon, title, host, model, status (running / awaiting answer / idle / exited), last activity. Spawn FAB; swipe/long-press to delete (confirm). Sessions awaiting an answer sort to the top — that's the "your turn" inbox.
  2. Spawn — kind, host (from config), model (Claude list is static+editable; llama list from config), working directory, permission mode (Claude), title.
  3. Session screen — the core:
    • Transcript rendered from the event stream: markdown text, inline images, collapsed-by-default tool cards (name + input summary, expandable to output; a spinner while ToolStart has no matching ToolEnd).
    • Question cards inline: option buttons for AskUserQuestion, allow/deny for permissions, free-text where allowed.
    • Input bar: text, attach (camera/gallery/file), send — always enabled; mid-run sends become steering messages.
    • Top bar: model chip (tap to change), stop button while running, token count, compact button (llama), overflow → delete.
  4. Usage — window bars for the 5-hour and weekly limits with reset times.
  5. Settings — server address + token, hosts editor, llama model list editor.

Networking mirrors dev-updater's app layer (AppsApi.kt style thin client + pinned transport), plus an SSE client with after= resume driven by connectivity/lifecycle. The app keeps no persistent transcript store — the backend's transcript is the source of truth; the app caches only for the screen it's showing.

Compaction: options explored

Context: raw llama-server has no conversation memory management; the context window just fills.

  1. pi's auto-compactionchosen. When the prompt nears the model's context limit, pi summarizes older history with the model itself and replaces it with a structured summary; threshold configurable; manual compact also exposed. Battle-tested, zero work for us.
  2. Manual compaction in a custom Rust loopthe later third driver. The design when we build it: every llama-server response reports prompt + completion token counts; track them against n_ctx (from /props); at a threshold (~75%), pause, run a summarization request over all but the last few turns ("state of the task, decisions made, open items, relevant file/tool state"), replace those turns with the summary as a system-adjacent message, continue. Keep the full pre-compaction transcript on disk — the phone view never loses history, only the model's view shrinks. Worth doing eventually for control over the summarization prompt and for tool-loop experiments pi doesn't allow.
  3. llama-server --context-shiftrejected as the strategy. It truncates old KV cache entries: silent forgetting, no summary, and it corrupts the harness's view of what the model knows. Fine as a server-side safety net; not memory management.

Phases

  1. Skeletondone 2026-08-24. Repo layout, cert script, TLS + token auth, wg0-bound listener (fail closed if the interface is missing), config.json, session registry with a fake EchoDriver, session list + session screen in the app end-to-end over SSE. Proves the whole pipe before any AI is involved. Verified: 10 server tests + clippy clean; curl end-to-end over pinned TLS (auth rejection, spawn, SSE replay/resume by cursor, question round trip, restart continuing seq numbers, delete); the app on the tdep emulator against the real server (QR-style enrollment via deep link, spawn, streamed echo turn, question answer, tool card).
  2. Claude localdone 2026-08-24. ClaudeDriver: spawn, stream text/tools, mid-run send, interrupt, permission questions, AskUserQuestion, images both ways, delete. Milestone: daily-drivable Claude replacement on localhost. Wire-format notes live in session/claude.rs's module doc (pinned against CLI 2.1.237): permissions need the hidden --permission-prompt-tool stdio flag; AskUserQuestion answers ride updatedInput.answers keyed by question text; set_model/interrupt are control requests; 2.x permission modes are acceptEdits / auto / bypassPermissions / manual / dontAsk / plan (no more "default"). Attachments/files were re-homed under /sessions/:id/… (table above) so their lifecycle is the session directory's — delete stays the complete path out.
  3. Usage screendone 2026-08-24. The undocumented endpoint's limits[] array parsed defensively into labeled window bars; cached behind the ≥180 s minimum with no background polling.
  4. llama.cpp — LlamaServerManager (local), PiDriver, model change, compaction controls. Deferred (2026-08-24): pi/llama-server aren't set up in this VM, so this phase isn't testable here — Claude first; the driver seam is ready when it is.
  5. SSH — host config, remote spawn for both kinds, remote llama-server with port forward, attachment shipping. Host config and remote spawn done 2026-08-25 (any session of any provider can name a host; the command is the identical one wrapped in ssh -T, with every argument shell-quoted). Attachment shipping turned out to be unnecessary for the Claude driver — images ride the stdio JSONL as base64 in both directions, so nothing needs scp. Still outstanding: remote llama-server with its port forward, which comes with phase 4. Two things learned doing it: a remote session inherits ssh's non-login PATH, which is narrower than an interactive shell's (point command at an absolute path if a CLI isn't found), and the remote command is run with exec so dropping the connection takes the CLI down rather than orphaning it.
  6. Polish — reconnect edges, notification when a session awaits an answer (the "your turn" push), transcript search, whatever daily use surfaces.

Each phase ends runnable and verified against the real thing (rule 22); the backend gets tests where logic is pure (event normalization, transcript cursors, config persistence, refcounting) — the app is UI over the API and is verified by running it, matching dev-updater's posture.

Open questions / risks

  • Claude stream-json control protocol details (permission requests, set-model, interrupt wire format) are the least-documented dependency and version-coupled to the installed CLI. Phase 2 starts by probing the installed version and pinning what works; the --resume respawn fallback covers whatever the control channel can't do.
  • The usage endpoint is undocumented and has changed rate-limit behavior before; treat as best-effort.
  • pi RPC schema drift — pin a pi version; the translator is one file.
  • Whether notifications need FCM or a foreground-service polling connection — decide in phase 6; the SSE cursor design already supports either.
  • Claude sessions over SSH need the remote host logged in to Claude; usage reporting reads only the backend host's credentials. Acceptable for now (same account everywhere); revisit if not.

References

Research behind the decisions above (verified 2026-08-24; re-check against installed versions when each phase starts):