Files
ai-agent/CLAUDE.md
Gabriel Vidal f9b1e40eae fix(hooks): cap post-task hook's context so it can't quietly re-pay the whole conversation
A resumed hook firing is a brand-new claude -p process, and Claude Code
rebuilds that process's environment preamble from scratch — any drift there
(near-certain on a shared checkout) invalidates the finished run's prompt
cache entirely. Sampled real transcripts confirm every firing re-creates the
whole prior conversation as fresh input tokens rather than reading it from
cache, regardless of delay. maxContextK was defaulted to 0 (no cap), so an
unbounded conversation meant an unbounded tidy-up bill. Default it to 60k and
document why, in both the backend docstring and CLAUDE.md.
2026-08-09 20:44:00 +02:00

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CLAUDE.md — ai-agent

Guidance for Claude Code when working in this repo. It was extracted from the homelab monorepo (formerly services/ai-agent/, full history preserved); the homelab keeps a deployment shim at ~/homelab/services/ai-agent/ (compose with build.context pointing here, traefik.yml, deploy.sh, the live data/ volume), and the homelab root CLAUDE.md conventions (worktrees, Traefik copy step, commit/notify) still apply when deploying there.

North star

This service is headed somewhere bigger than a homelab dashboard: the open-source, intuitive, private and secure agent layer of any computer, to build and host websites and interact with data — Lovable, but open source and self-hosted. Zipgo under the hood for hosting, shipped as a single Docker container, with self-update handled inside the container (not by host scripts). See GOAL.md for the full vision and the gap list. When making changes here, prefer container-internal solutions, generic config over homelab-hardcoded paths, and zipgo over bespoke hosting.

What this is

A viewer/editor + analytics dashboard for the homelab's Claude context, served as an installable PWA at https://ai-agent.lab.gabvdl.xyz (behind Authelia). It:

  • exposes every CLAUDE.md and the .claude/ tree (skills, hooks, settings) as a flat, editable file list with real Claude token counts + dollar costs, plus the repo's root data/ tree (plans, logs, notes, kanban) surfaced read-only;
  • browses the archived Claude Code conversation transcripts (thread view with per-turn usage/cost, skill-usage analytics, spawn/resume/interrupt live runs);
  • catalogs ~/projects (mounted at /workspace/projects; gallery + detail) and the repo's services/ (static parse of compose + Traefik configs — never Docker itself);
  • surfaces the assistant's memories and the scaffolding templates;
  • streams updates over SSE so the UI refreshes without a manual reload.

It is a viewer: it reads the repo context (mostly read-only mounts) and does static parsing. It never drives Docker or mutates infrastructure. The only writes are file edits into the mounted .claude/ + ~/projects trees and its own SQLite store / metadata sidecar.

Layout

  • backend/ — FastAPI app (main:app, port 8080). Serves /api/* and the built PWA from STATIC_DIR (SPA catch-all at the end of main.py).
  • frontend/ — Vite + React + TS + Tailwind PWA. Built in the Dockerfile's first stage into /app/static.
  • sidecar/ — a host-side FastAPI process (NOT in the container) that launches claude -p sessions. See below.
  • Dockerfile — 2 stages: build the React PWA, then a python:3.12-slim image running uvicorn.
  • docker-compose.standalone.yml — the generic, no-host-mounts shape (see "Standalone mode" below). The homelab's compose service (profile dev, container ai-agent, host-only port 127.0.0.1:8096:8080, network main), its Traefik router (ai-agent.lab.gabvdl.xyz, auth-chain) and the blue-green deploy.sh + deploy.override.yml live in the homelab repo's services/ai-agent/ shim.
  • PROJECT_CLAUDE.md — the generic, host-agnostic project working conventions (worktree workflow, artefacts, plans, committing, the notify+DONE finish signal), split out of the homelab root CLAUDE.md so the ai-agent can ship it as the starting CLAUDE.md for a new project. Not this service's own guidance (that's this file) — it's a shippable template with {{…}} placeholders.
  • data/ — SQLite DB, transcript archive, metadata sidecar, ui-state.json (bind-mounted, gitignored).

Backend modules

  • main.py — FastAPI app, all routes, env/path wiring, startup (indexer + watcher).
  • db.py — SQLite store (WAL): files (content hash + real token count + cost + word/char stats, computed lazily only when a file's hash changes), skills, transcripts bookkeeping. Decoded transcript summaries are cached in-process (all_summaries()/get_summary() return read-only dicts — copy before mutating) and summaries_version bumps on change so request-level memoizers (e.g. the project cost rollup) know when to recompute.
  • indexer.py — background daemon: token/cost accounting (via the count_tokens endpoint, debounced) + skill-usage mining from transcripts. Pricing consts here.
  • conversations.py — parse *.jsonl transcripts. ParserState is a resumable parser (feed(record) + summary()); parse_conversation(path, full=…) is the one-shot wrapper (cheap rollup vs. full thread). Real per-turn usage/cost from usage blocks, plus the per-item metadata the viewer shows on each row: durationMs (a tool call's run time — call → its result record; on a message, the assistant API call's latency), model, toolUseId, resultChars/resultLines.
  • fsscan.pyos.scandir-based directory walking. The poll loops re-walk thousands of files every couple of seconds; pathlib.rglob allocates a Path per entry and was a large chunk of idle CPU. Use this, not rglob, in any loop.
  • githist.py — cached git history. BucketedHistory walks a repo's log once (git log --name-only -- <prefix>) and buckets commits per directory, keyed on the repo HEAD; RepoLogCache TTL-caches standalone project repos. Before this, /api/services forked two git logs per service per request (11 s).
  • events.pyHub (SSE pub/sub) + Watcher (polls meta + live transcripts, re-indexes, publishes meta/transcript events).
  • meta.py — per-conversation action metadata JSON sidecar (projects, state, committed/pushed/merged/deployed/notified timestamps), keyed by session id.
  • cron.py — cron jobs: scheduled agent sessions (Settings → Cron). A job = a 5-field cron schedule (dependency-free matcher, container-local time — TZ in compose) + a prompt file under .claude/agents/ whose content (frontmatter stripped) is spawned as a session via the normal sidecar path; each firing is recorded in the job's history ({timestamp: sessionId}) and the conversation is tagged (meta.cron → violet badge linking back to the job). How a job runs is declared in that file's frontmatter — see below. Store is /data/cron-jobs.json (seeded with the every-5h goal-keeper job on first run); the scheduler thread claims each fire minute through the store, so the deploy-cutover window where two backends share /data can't double-spawn. REST under /api/cron (+ /run, /prompt); mutations and fires publish a cron SSE event.
  • hooks.py — conversation hooks: follow-up prompts fired after a run finishes (Settings → Hooks). Cron's twin, with two differences — the trigger is an event (conversation-done) plus a delay instead of a schedule, and a firing resumes the conversation that just finished rather than spawning a new one. Store is /data/hooks.json, holding the hooks and a persistent pending queue so a queued firing survives a restart; seeded with the enabled post-task hook (delay 10s, prompt written to .claude/agents/hooks/post-task.md on first run). REST under /api/hooks (+ /run, /prompt) plus the read-only /api/claude-hooks; mutations and fires publish a hooks SSE event. See "A hook fires once per conversation" below.
  • models.py — the models a session can run on (GET /api/models). Fetched from the Anthropic API (/v1/models, same key the token counter uses) and cached in-process for 6h, then reduced to the newest of each family (opus, sonnet, haiku, fable — older snapshots are dropped, so the tag row stays four chips) with the CLI alias attached. A newly released model appears in the composer with no code change. Falls back to a small static list when the key is missing or the call fails.
  • ui_state.py — server-side store (/data/ui-state.json) for the PWA's small client state (Settings config + notification feed seen/new bookkeeping), moved off browser localStorage so it follows the user across devices. Dumb key→string map: the key is a Zustand persist store name, the value its opaque serialized blob. Served by GET/PUT/DELETE /api/ui-state/{key}; the frontend points its persist stores at it via frontend/src/lib/serverStorage.ts.
  • projects.py / svc.py — projects gallery / services catalog (static parsing).
  • skills.py — the skills catalog behind /api/skills (the /skills page): a disk scan of every .claude/skills/<name>/SKILL.md (repo + each project's) joined with the transcript-mined usage. /api/skills returns the union of disk skills and invoked-skill names, so a built-in/plugin skill with no SKILL.md here still shows up (sourceKind: "builtin", no editor link). Per skill: calls, distinct conversations, last-used, context tokens/cost (loading its dir once), estSpend = context × calls, and the coarser sessionCost (whole spend of every conversation that invoked it). Usage is keyed by bare skill name — the identity Skill(name) itself uses — so a project-local skill sharing a repo skill's name shares its counts.
  • goal.py — a dir's GOAL.md (the north star the goal-keeper cron agent pushes forward), shared by both catalogs: goal_summary() returns the {done, total} checklist rollup that tags a card, goal_detail() adds the markdown for the detail page. Counting skips fenced code blocks, so a - [ ] inside a snippet isn't mistaken for a real task. No GOAL.md ⇒ goal: null (a valid state).
  • memories.py — surfaces the assistant's per-repo memory files (frontmatter).
  • templates.py — browse ~/projects/templates/ scaffolds.
  • schemas.py — Pydantic response models mirroring frontend/src/types.ts. They drive the OpenAPI schema (and thus the generated frontend types) but are documentation-only: attached to routes via responses={200: {"model": …}} (helper _r() in main.py), never response_model, so FastAPI serves them in /openapi.json without validating or filtering the handlers' actual dicts.

API types are generated (orval)

The frontend's API DTOs are generated from the backend's OpenAPI spec, not hand-maintained. Flow: backend/schemas.pyfrontend/openapi.json (a dumped spec, committed) → orval → frontend/src/generated/ (committed) → re-exported by frontend/src/types.ts under their original names. types.ts keeps only the non-API helpers (TreeNode, FileKind, ServiceAuth).

  • After changing a backend response shape, update the matching model in schemas.py, re-dump frontend/openapi.json from the app's app.openapi(), then cd frontend && npm run gen:api to regenerate, and npx tsc --noEmit to surface fallout. Generated optionals are T | null (Pydantic Optional), so widen consumers to accept null — the app runs unchanged; only tsc cares.

  • The Docker build doesn't regenerate (no backend at build time) — it relies on the committed src/generated/ tree, so commit regenerated output.

  • There's no venv on the host, so re-dump the spec with the service's own image:

    docker run --rm --entrypoint python -v "$PWD:/svc" -w /svc/backend \
      -e DB_PATH=/tmp/x.db -e TRANSCRIPTS_DIR=/tmp -e WORKSPACE=/tmp -e REPO_DIR=/tmp \
      homelab-ai-agent -c \
      "import json, os, main; json.dump(main.app.openapi(), open('/svc/frontend/openapi.json','w'), indent=2); os._exit(0)"
    

    Both odd-looking bits are load-bearing: --entrypoint python because the image's entrypoint (docker-entrypoint.sh) otherwise ignores the command and boots the server, and os._exit(0) because importing main starts the indexer/watcher threads, so a normal exit hangs waiting on them.

    It runs as root, so delete the backend/__pycache__ it leaves behind (a root-owned dir will otherwise block git worktree remove).

The mock backend (frontend/src/mock/) — demo + test without the API

The frontend ships an in-browser mock backend that sits behind those same generated DTOs, so the PWA can be demoed and automatically tested with no FastAPI, no sidecar and no transcripts on disk. Turn it on with ?mock=1 on any URL (sticky until ?mock=0 — works against the deployed app too) or build/serve with VITE_MOCK=1 (npm run dev:mock); a MOCK API badge marks the mode.

It swaps window.fetch (every /api/* route) and window.EventSource (/api/events, same meta/transcript events as backend/events.py) for versions served from an in-memory, localStorage-persisted database. Writes really mutate it, and spawn/resume/interrupt actually run: a scripted turn streams into the conversation item by item over SSE, then stamps the notification + DONE that mark it finished.

The seed is combinatorial — the cross-product of every field the UI branches on (conversation harness × state × lifecycle × archived, every ThreadItemKind and tool card, every FileEntryKind, every service auth, every plan status, every FileDiffStatus/DiffLineType) — so every visual state is reachable from a cold load, and it is deterministic (fixed clock, no RNG). Test hooks live on window.__mock (db(), reset(), speed(), flush()).

Two rules keep it useful: install it before the app tree is imported (main.tsx → dynamic ./mock, then dynamic ./root; the server-backed Zustand stores fetch at import time), and type the seed rows with the generated models — a backend schema change then breaks the seed at tsc time instead of letting the mock drift. Details in frontend/src/mock/README.md.

Every new piece of conversation data gets a visibility toggle

The conversation page has an eye-icon visibility popover (components/ VisibilityPopover.tsx, switches + store in lib/visibility.ts) — a scrollable, grouped list of switches for everything the page renders: per-item metadata (price, tokens, duration, timestamp, model, tool id, result size, diff stat), content (thinking blocks, tool cards, run-command cards, tool output, rich widgets, error states) and gizmos (task panel, fast-forward, animations). State persists server-side via ui-state under the key ai-agent-visibility, so a reading setup follows the user across devices.

When you add anything to a message, a tool card or the conversation chrome, add its switch too — a new metadata field, a new inline widget, a new floating gizmo, a new animation. It is not optional: the thread is dense, and every addition has to be something the user can turn back off.

To add one: append a VisItem to the right group in VIS_GROUPS (lib/visibility.ts) — the VisKey union, the popover list and the persisted state all derive from that array — then gate the render on useVis() (or useVisible(key) for a single switch). The store records only what's hidden, so a newly added switch starts ON for everyone with no migration.

Fixed lists are rearrangeable: HoldEditable + useListOrder

Small lists of links, chips or cards are user-arrangeable by holding one for 1.4s: it lifts out of the flow and follows the pointer, the rest of the group starts jumping (iOS-springboard style), dragging into a neighbour's slot hands it over, and releasing drops it there and ends edit mode. All of it lives in technical/ui/HoldEditable.tsx — pointer-events only (one code path for mouse and touch) and a body-level portal for the lifted item so nothing clips it. It's layout-agnostic: the group's flex/grid classes come from the caller, so the same component drives a horizontal navbar and a vertical panel (one row or column — not a wrapping grid).

The DOM order never changes during a drag. Slots are measured once at pickup and the rearrangement is expressed purely as transforms; only the drop commits a real reorder, once the pointer is gone. This is load-bearing, not tidiness: reordering live means React moves the pressed node — and re-renders whichever item now sits in a position-dependent slot, like the navbar's raised centre tab — and a browser cancels the touch whose target left the document, so the drag died on the first hand-over. For the same reason the held item's (invisible) in-slot copy keeps rendering with the props it had before the pickup: its node must not be replaced. Freezing the DOM also fixes the geometry, so hit-testing needs no re-measuring and no animation lock, and a fast drag can't outrun the shuffle.

const [tabs, setTabs] = useListOrder("nav", TABS, tabKey);   // lib/listOrder.ts
<HoldEditable items={tabs} getKey={tabKey} onReorder={setTabs} className="flex …">
  {(tab, { index, held, editing }) => <Tab />}
</HoldEditable>

For a list that is the data (prompt shortcuts), pass the array and write it back. For a list hard-coded in the app, useListOrder(name, items, getKey) persists only the order, as ids, under settings.listOrders[name], and reconciles it against the code list on read — so adding, renaming or removing an entry in a later release can never strand or duplicate an item. Already wired: the bottom navbar (nav), the dashboards / settings / files drawer panels, and the prompt-shortcut cards.

A hold ends in a click, so HoldEditable swallows the click that closes a drag — otherwise rearranging the navbar would also navigate. Presses that start inside an input/textarea/select/[contenteditable] (or anything marked data-hold-editable-ignore) never pick up.

Travel during the hold cancels it only for a finger (>12px), where it means "I'm scrolling, not holding". A mouse is deliberately exempt: it can't scroll with the button down, and a hand resting on one drifts far more than that over 1.4s — cancelling on drift made hold-to-drag impossible on desktop. The pickup then happens wherever the cursor ended up, not where it went down.

Performance: what the hot paths cost, and the rules that keep them cheap

This service polls the filesystem continuously and serves lists built from ~900 transcripts, so the naive version of almost anything here is quadratic. Four rules, each of which was once a real regression:

  1. Never walk the workspace (or the transcript dirs) per request or per tick. The file catalog comes from the files table; the discovery walk is cached in the indexer (_exposed_files, refreshed every WALK_INTERVAL_SECS, forced on save). The watcher tells the indexer which transcripts changed (scan_transcripts(only=…)), so a live turn re-parses one file instead of re-walking ~2 600. Walk with fsscan.walk_files, never rglob.
  2. Never re-parse a whole transcript to see what was appended. A live session writes every couple of seconds; the indexer keeps a ParserState per growing transcript and feeds it only the new lines (byte offset in Indexer._live). Re-parsing from byte 0 each tick is O(n²) over a session.
  3. Never shell out to git per item. Both catalogs share one HEAD-keyed history walk (githist).
  4. Never send content you don't need. /api/bundle is metadata-only (content loads per-file via /api/file); /api/conversations is paginated + lite (usage/byToolSub only under full=1, which only the analytics dashboard asks for); an SSE transcript ping patches one row via /api/conversation-summary instead of refetching the list.

Measured on the real archive (898 transcripts / 458 MB): /api/bundle 12.5 s → 26 ms, /api/services 11.2 s → <1 s cold / 0.5 s warm, /api/projects 3.4 s → 0.35 s, the conversation list 1.3 MB → 89 KB, and idle CPU ~58% → ~7% while a session streams. If you add a feature here, check it against the four rules — and re-measure, don't assume.

Security: the trusted-caller gate

The backend has no auth of its own — Authelia guards it at Traefik. But the container also sits on the shared main docker network, where a PUT /api/file into .claude/ (hooks!) or a POST /api/spawn is host-level code execution. So main.py has a middleware that answers /api/* only for: Traefik (resolved from TRAEFIK_HOST), the docker gateway (how host-originated connections to the published 127.0.0.1:8096 port appear), localhost, or a caller presenting INTERNAL_API_TOKEN. Everything else gets 403; /api/health stays open for the deploy probe.

Read-only API keys (READONLY_API_KEY, comma-separated) are the one credential that is checked before the trusted-IP path: a caller presenting a matching X-API-Key is allowed safe methods only (GET/HEAD/OPTIONS) and any mutating method is 403 — even from an otherwise-trusted source IP. That downgrade is the point: the desk phone reaches the backend over the trusted host loopback but must only ever read (it fetches GET /api/notifications/unread to read notifications aloud), never spawn a session or PUT into .claude/. The unread endpoint is a pure read — it never advances the read ledger (notif_read.py / /data/notif-read.json); only the PWA opening/dismissing a card (or POST /api/notifications/seen) marks notifications read. Assets served from repo/user bytes (/api/data-asset, /api/upload-file, …) go out nosniff and, unless they're an allow-listed raster image or video, Content-Disposition: attachment — an uploaded .html/.svg must never execute on the app's origin.

The runner: same sidecar, two places it can run

sidecar/sidecar.py is the only thing that launches claude -p. It runs in one of two places, and the backend doesn't know the difference — it just POSTs to SIDECAR_URL:

  • On the homelab host (the default, below): a run then has the host user's own auth, hooks, skills and CLAUDE.md — i.e. it is exactly a session started from a terminal. This is why the homelab keeps it.
  • Inside the container (RUNNER_IN_CONTAINER=1, the standalone default): the image bakes in the Claude Code CLI (a self-contained native binary — see the Dockerfile) and docker-entrypoint.sh starts the same sidecar module on 127.0.0.1:8790, mints a SIDECAR_TOKEN if none was given, and overrides SIDECAR_URL to point at it. The CLI's $HOME is RUNNER_HOME (/data/home, on the data volume), so its config, credentials and the transcripts it writes survive a restart; RUNNER_TRANSCRIPTS_DIR (defaulted from it) is added to the backend's live SOURCE_DIRS, which is what makes an in-container session stream into the viewer like any other. Auth is ANTHROPIC_API_KEY, or an already-logged-in Claude home mounted at RUNNER_HOME (-v ~/.claude:/data/home/.claude). Remote control is off by default there (it needs an interactive login).

That's GOAL.md's "single Docker container": a standalone image spawns sessions with no host process. Keep it that way — a new runner feature belongs in sidecar.py, not in a host script.

The host sidecar (what the homelab runs)

sidecar/sidecar.py runs natively on the host as the repo owner and the backend proxies to it over host.docker.internal:8790 (Bearer SIDECAR_TOKEN):

  • POST /api/spawn → sidecar /spawn: claude -p <prompt> --session-id <uuid> --model <model> --remote-control (detached). Transcript lands in the watched projects dir and the new conversation shows up in the viewer within ~2s.
  • POST /api/resume / POST /api/interrupt → continue / SIGINT an existing run.

model is the claude --model argument the composer's model tag carries — a family alias (opus) for a family's newest model, or a pinned id (claude-opus-4-5-20251101) for an older one. Unset on spawn ⇒ SIDECAR_MODEL (default opus); unset on resume ⇒ no --model flag, so the session keeps its own. The sidecar only shape-checks the value (it goes on a command line) — the pickable set is whatever /api/models returned.

Model tags

Models are a first-class tag on both sides of the app (frontend/src/lib/models.tsx): picking one in a composer (a mutually-exclusive chip per model — RichInput's exclusive key, added in @gabvdl/ui ≥0.11) runs that session on it and the toolbar echoes the choice; the pick is sticky (spawnModel in Settings, stored server-side). Reading back, a conversation is tagged with every model that actually produced a turn — conversations.py collects them (models, busiest first; a session can switch mid-thread), so past conversations are tagged too (bump PARSER_VERSION to force the re-parse that back-fills a new summary field).

Effort (claude) vs. thinking (pi)

How hard a run works a turn is one knob shown two ways, per harness — never both at once:

  • claude gets an EffortSelect (--effort low|medium|high|xhigh|max), the CLI's own scale. Sticky as spawnEffort; "" means "send no flag" and let the CLI default. The sidecar validates against an allow-list (EFFORT_LEVELS), unlike --model, because the scale is a closed set.
  • pi keeps the binary ThinkingToggle — it has no --effort. _effort_args emits nothing for it, so a stale pick can't leak onto a pi command line.

The composers send only the active harness's control (the other goes out unset). Reading back, conversations.py mines the effort field the CLI stamps on each assistant record (it rides on the record, not the message) into efforts, busiest first — same shape as models, rendered by EffortTags on conversation rows and in the detail header. Empty for pi runs and for transcripts predating the flag, which is a valid state, not a blank chip.

A cron job's run config lives in its prompt file's frontmatter

A scheduled job has no composer to pick a harness/model/effort in, so it says so itself: the leading YAML block of .claude/agents/<job>.md carries harness (claude|pi), model (a family alias or a full id), effort (low|medium|high|xhigh|max, or none for no flag) and thinking (true|false). cron.run_config() reads them, _fire_cron_job passes them to the same _send_message the composer uses, and the resolved config comes back on the job as runConfig so Settings → Cron shows it as chips. Every homelab job currently declares claude + sonnet + no effort.

Two deliberate properties: the keys are a subset of Claude Code's own agent frontmatter (model means the same thing there), so a job's prompt file stays a usable .claude/agents subagent; and an invalid value is dropped, not raised — a firing on the defaults beats a job that stops firing, and the missing chip in the UI is the feedback. The store's per-job model field is now only the fallback for a file whose frontmatter sets none.

A hook fires once per conversation, and that is the whole design

A conversation hook resumes the session that just finished. The follow-up run ends with DONE and exits too — which is exactly the signal that queued it — so the naive version loops forever. Two things stop that, and neither is optional:

  • The ledger. Every firing stamps meta.hooks[hookId] = iso on the session before the resume is sent. MetaStore.update merges that mapping instead of replacing it (a replace would let every earlier hook fire again), and both the enqueue path and the due-time preconditions refuse a stamped pair. One firing per (hook, session), ever. POST /api/hooks/{id}/run is the deliberate exception — a manual re-fire.
  • The claim. The pending queue lives in the same JSON as the hooks, and the scheduler removes an entry (re-reading the file first) before firing it, so the deploy-cutover window where two backends share /data can't double-resume.

Queuing happens in two places, because a conversation can finish two ways: the exit watcher (_mark_run_exited) and POST /api/notify (terminal-launched runs the sidecar never saw). Both call _enqueue_hooks(sid), which is best-effort — a hook must never break the finish path.

The preconditions are checked at due time, not at enqueue time, because the conversation may have been resumed, interrupted or archived in the meantime. They return one of three verdicts: go, postpone (still live, transcript not synced — re-queued a minute later, up to hooks.MAX_RETRIES) or skip (settled: already fired, cron-spawned, a subagent, interrupted/paused, no DONE marker, or over the hook's context cap). A skip is a normal outcome, not a failure, and the page's status chip colours it amber rather than red.

The context cap is a cost control, not a nicety — a resume doesn't hit the finished run's prompt cache. --resume is a fresh claude -p process, and Claude Code rebuilds that process's environment preamble (cwd, git status, date, …) from scratch; any byte of drift there (near-guaranteed on a checkout other agents are also committing to) invalidates every cache breakpoint after it. Sampled real transcripts confirm it: cache_read_input_tokens collapses to the small cross-session baseline and cache_creation_input_tokens re-creates the entire prior conversation, every firing, regardless of the delay. That cost tracks the original conversation's size, so maxContextK: 0 means an unbounded tidy-up bill. See hooks.py's module docstring for the detail; the seeded post-task hook now defaults to maxContextK: 60.

A firing passes model/effort/thinking as None unless the prompt file's frontmatter sets them, which _send_message reads as "keep whatever the session already ran with" — a follow-up must not silently switch models mid-conversation.

Native Claude Code hooks (.claude/settings.json) are read-only here (GET /api/claude-hooks, listed at the bottom of the page): writing that file from the container would be host-level code execution — see the trusted-caller gate above.

Install/manage the sidecar with sidecar/install.sh (systemd user unit claude-sidecar); config comes from the repo .env (SIDECAR_TOKEN, SIDECAR_PORT). See sidecar/README.md.

Schema drift: the transcript format is not ours

backend/conversations.py parses Claude Code's internal, undocumented JSONL transcript format, so a CLI update can silently change what it emits. The early-warning tool is scripts/schema-drift.py:

scripts/schema-drift.py            # newest transcripts vs committed baseline
scripts/schema-drift.py --update   # accept reviewed drift as the new baseline

It does two things: diffs a structural footprint (key paths + content-block types, never values — scripts/schema-baseline.json is safe in git) of recent ~/.claude/projects transcripts against the baseline, and runs a parser canary (the real parse_conversation cross-checked against raw record counts: assistant turns with usage, token totals, models, timestamps). Exit 1 on drift or a failed invariant. Run it after a Claude Code update or whenever conversations render oddly; on drift, decide whether the parser needs to handle the new shape, then --update. Every transcript record carries the CC version stamp — a new version alone is INFO, not failure (releases are ~daily and almost never drift).

Deploying

Never compose up --force-recreate this service — use the blue-green script, which validates a fresh build on a standby container before touching the live one:

~/homelab/services/ai-agent/deploy.sh   # the homelab shim's copy (runs from anywhere)

It builds a new image, brings up a second ai-agent-deploy standby on homelab_main, health-gates it on /api/health, cuts Traefik over to it (file-provider hot-reload), recreates the canonical ai-agent on the new image, then restores routing and removes the standby — zero downtime, and if the standby never goes healthy the live container is left untouched. An flock on /tmp/ai-agent-deploy.lock serializes deploys; a second run aborts immediately. deploy.override.yml is only for the standby slot (renames the container, drops the host port, joins the external homelab_main network).

Standalone mode: a missing catalog is a valid state

The homelab docker-compose.yml mounts ~8 host paths (transcripts, memories, screenshots, services/, plans, …), but the image must also run with none of them — that's the GOAL's "generic first-run setup" / one-liner docker run. docker-compose.standalone.yml is that shape: a workspace + a data volume, and nothing else required.

So every catalog degrades to an empty list when its dir is absent — never a 500. (/api/templates used to raise; it doesn't now.) A named item that isn't there is still a 404 — it's only the missing-mount case that's benign. When you add a catalog backed by a mount, follow that rule.

The guard is a smoke test — run it after touching mounts, env wiring or a catalog route:

scripts/standalone-smoke.sh            # boot the current image on a bare workspace
scripts/standalone-smoke.sh --build    # build first, then smoke

It boots the image with only a throwaway workspace + data dir (and RUNNER_IN_CONTAINER=1), asserts every catalog endpoint and the PWA shell answer 200, that the bundled claude CLI is on PATH and its runner answers /health, and greps the log for tracebacks (a background indexer/watcher crash won't fail a request). Exit 1 = regressed.

Standalone spawns sessions now (the in-image runner, above). The one thing it still can't do is build off-homelab: frontend/.npmrc pulls @gabvdl/ui from the host-bound verdaccio, so a standalone build needs that registry — a prebuilt image runs anywhere. Tracked in GOAL.md.

Local development

There is no lint/test pipeline. Frontend and backend are built into the image; to iterate:

  • Frontend only: cd frontend && npm install && npm run dev (Vite on :5180). It needs the backend API — point it at a running container or backend.
  • Full stack: rebuild + redeploy via the homelab shim's deploy.sh, or hit the running container directly on the host at http://127.0.0.1:8096 (plain HTTP, bypasses Authelia — handy since new *.lab domains can't get an LE cert here).
  • Health: curl -s http://127.0.0.1:8096/api/health{"ok":true}.

After changing the homelab shim's traefik.yml, run make link-traefik-configs from the homelab repo root (the file provider watches config/dynamic/, not the shim's file).

Gotchas

  • Read-only mounts: most of the repo context is mounted :ro (services/, .git, transcripts, memories, screenshots, and the root data/ tree). Only .claude/, ~/projects (host-side; /workspace/projects in-container), CLAUDE.md and the service's own data/ (SQLite store) are writable. The container runs as 1000:1000 so edits keep repo ownership.
  • Root data/ tree: mounted ${PWD}/data:/workspace/data:ro and surfaced in the file tab for visibility only. The indexer exposes just text files (see DATA_TEXT_EXTS in main.py — md/json/py/log/…; binaries like the PNG thumbnails are skipped) and marks them non-editable. data/tmp/ is in IGNORE_DIRS, so scratch files and secrets (e.g. *-creds.env) never appear.
  • Token counts cost API calls: they hit the count_tokens endpoint (ANTHROPIC_API_KEY from .env) and are recomputed only when a file's content hash changes, after a debounce — don't add code that recounts on every request.
  • Conversation "finished" state: three signals, strongest first. (1) A notify-done notification plus a last message ending with the literal DONE marker (see the root CLAUDE.md "When work is done"). (2) The exit watcher: a background thread in main.py (_watch_sidecar_runs) polls the sidecar's /sessions every ~2s and stamps finished (+exitedAt) the moment a sidecar-launched run's process dies — so runs whose prompt never said DONE don't sit on "running". The stamp is distrusted if the transcript later grows past exitedAt (a terminal/remote-control continuation, _outlived_exit), and in-flight resume/interrupt swaps are shielded via _sidecar_busy. (3) The recency fallback (RUNNING_WINDOW_SECS, 600s) for anything the watcher never saw live (terminal sessions, runs that died while the backend was down).
  • Conversation "paused" state: a run whose last act was parking itself on a trigger — a trailing ScheduleWakeup (non-stop) or a pending Monitor — is shown paused instead of running (waiting_trailing in conversations.py, resolved in main.py:_resolve_state). The flag clears on any later tool call, real user turn, or interrupt — not on the same turn's closing text.
  • Two containers briefly share data/ during a deploy cutover (SQLite); this is a short window and intentional — don't "fix" it by locking the DB.
  • A resume must never answer 200 without a live run behind it. The composer echoes the typed turn optimistically and only drops the echo once the transcript grows, so any resume that reports success but starts nothing leaves the UI on "sending…" forever. Two guards keep that honest and must stay: sidecar.py watches a freshly launched claude for LAUNCH_PROBE_S and 502s with its log tail if it dies on the spot (a --resume whose transcript isn't found exits 1 in ~2.5s), and /resume only reports reused for a process that is genuinely still running — a finished-but-unreaped child is a zombie, and a zombie answers os.kill(pid, 0) (hence _reap() + the Z check in _alive). reused means the turn was dropped, so the backend returns 409, not 200. The backend always resumes with force: true: a genuinely-live run is stopped first (_stop_run — SIGINT the group, wait up to STOP_WAIT_S, escalate to SIGKILL) and the resume then launches, so sending a message into a running or paused conversation restarts it on the new turn instead of 409ing. reused can now only come from a sidecar predating the flag.