imprnt-plugin-kleinanzeigen

A watcher for your Kleinanzeigen message box. It mirrors incoming buyer messages, sorts each one with deterministic code (regex + arithmetic, zero LLM), drafts replies from per-listing fact sheets, and sends you a phone-sized digest. You tweak a draft and run send. It never sends on its own.

It's the first watcher-class plugin: code reads the hostile inbox, the model only ever drafts the handful of messages the rules can't place, and the send button stays human. An inbox full of scammers and lowballers is exactly where you do NOT want a resident agent with account access — a regex can't be social-engineered. (See Plans/05-kleinanzeigen-watcher.md in the repo for the full design.)

What it does, on one real day

Sixteen buyer messages on two router listings, one afternoon:

Kleinanzeigen — 3432924231: 14 new · 3432924164: 1 new
⚠ David Thiess [scam: paypal, name-mismatch, instant-full-price] — no draft, do not reply
Frank Pürschel [offer 70€ (below floor)] — your call
Erik [faq] — needs you: confirm artikelnummer
Nima [faq] — needs you: confirm artikelnummer, cable
Pavel [faq] — needs you: confirm age
Karla [pickup] draft: "Hi, Abholung ist möglich in Berlin. Wann würde es dir passen? ..."
Chitwan [interest] draft: "Hi, ja, FRITZ!Box 6660 Cable ist noch verfügbar. ..."
...

The scammer is caught by three named tells, no model involved. The five "what's the Artikelnummer?" questions surface what you need to confirm once (then they self-answer forever). The pickups and interest get ready-to-send drafts. You spent zero tokens to get here.

Commands

| Command | What it does | |---|---| | node kleinanzeigen.js sync | Refresh the mirror from the message box. The only command that touches the network. Offline with KLEINANZEIGEN_FIXTURES=<dir>. | | node kleinanzeigen.js rate | Classify each conversation. Pure regex, zero LLM. | | node kleinanzeigen.js notify | Compose the digest, ship it via $WATCHER_NOTIFY_CMD (stdout if unset). | | node kleinanzeigen.js send <conv> "<text>" [--force] | Post ONE reply. Refuses a scam-rated conversation without --force. | | node kleinanzeigen.js probe | (run once, logged in) discover live endpoints → endpoints.json. | | node check.js | Integrity: mirror staleness, missing fact sheets. Found by imprnt check --all. |

Authentication (live, automatic)

The message-box gateway authenticates with Authorization: Bearer <access_token>, a JWT the web app holds. Rather than make you export cookies on a short-lived token, sync reads it straight from your logged-in browser on this Mac — Arc by default, then Chrome / Brave / Edge. It copies the cookie DB (including the -wal file so a just-refreshed token isn't missed), decrypts with the key from your macOS Keychain (you approve a Keychain prompt the first time), and pulls the access_token. Local, on-demand, your own session — nothing leaves the machine. Stay logged into kleinanzeigen.de in the browser and sync just works.

Overrides, for non-Arc / headless / CI:

• KLEINANZEIGEN_TOKEN=<jwt> — use this Bearer token directly (skip the browser read).
• KLEINANZEIGEN_COOKIES=<file> — a file holding access_token=<jwt> (or a raw JWT).

Caveat: a launchd/cron run has no GUI to approve the Keychain prompt. Grant "Always Allow" once (or use KLEINANZEIGEN_TOKEN) for scheduled syncs. The token is short-lived, so scheduled use leans on the browser staying logged in and the Keychain grant persisting.

Environment variables

• KLEINANZEIGEN_FIXTURES — a directory of conversation JSON. When set, sync reads from there instead of the network, so the whole pipeline runs offline. The shipped fixtures/ is a sanitized inbox.
• KLEINANZEIGEN_TOKEN / KLEINANZEIGEN_COOKIES — the auth overrides above.
• WATCHER_NOTIFY_CMD — the channel for notify. The digest is piped to this command's stdin. Examples: curl -s -d @- "https://api.telegram.org/bot$TOKEN/sendMessage?chat_id=$CHAT&text=" (Telegram bot), ntfy publish mytopic, or terminal-notifier. Unset → the digest prints to stdout.

Fact sheets

Each listing gets a listings/<id>.yaml with the answers buyers ask. A FAQ is answered from these WITHOUT the model. An empty field is honest "not confirmed yet" — the rater turns it into a needs_fact in the digest rather than guessing. Fill it once; every future FAQ on that field answers itself.

listing: 3432924231
model: FRITZ!Box 6660 Cable
artikelnummer:            # empty -> "needs you: confirm artikelnummer" until you fill it
price: 90
floor: 75                 # an offer below this is flagged, never auto-accepted
pickup_area: Berlin

Wiring the live transport (the probe step)

Kleinanzeigen has no public API, so the endpoint shapes come from a logged-in capture, once:

# 1. Log into kleinanzeigen.de, open Messages, devtools → Network → "Save all as HAR with content".
# 2. Point probe at it — it extracts the gateway base + your userId and writes endpoints.json:
node kleinanzeigen.js probe --har ~/Downloads/www.kleinanzeigen.de.har
# 3. Done. Live sync reads the auth token from your browser session (see Authentication):
node kleinanzeigen.js sync

endpoints.json is gitignored (it holds your numeric userId). The read path is fully wired (list + per-conversation detail for full bodies). Send needs one more capture: replyPath in endpoints.json is null until you capture the POST that fires when you send a message (devtools → Network), because guessing a POST shape risks mis-sending. Until then send refuses live and you can use KLEINANZEIGEN_DRY_RUN=1 to rehearse. Sync/send fail loud with guidance, never a silent no-op.

Scheduling (you opt in; nothing is a daemon)

A launchd agent that syncs, rates, and notifies every 15 minutes (macOS). The send step is never scheduled — it's yours.

<!-- ~/Library/LaunchAgents/com.imprnt.kleinanzeigen.plist -->
<dict>
  <key>Label</key><string>com.imprnt.kleinanzeigen</string>
  <key>ProgramArguments</key>
  <array>
    <string>/bin/sh</string><string>-c</string>
    <string>cd /path/to/vault/plugins/kleinanzeigen && node kleinanzeigen.js sync && node kleinanzeigen.js rate && node kleinanzeigen.js notify</string>
  </array>
  <key>StartInterval</key><integer>900</integer>
  <key>EnvironmentVariables</key>
  <dict>
    <key>WATCHER_NOTIFY_CMD</key><string>curl -s -d @- "https://api.telegram.org/bot.../sendMessage?..."</string>
    <!-- For headless runs where the Keychain can't prompt, set KLEINANZEIGEN_TOKEN to a current JWT. -->
  </dict>
</dict>

launchctl unload ~/Library/LaunchAgents/com.imprnt.kleinanzeigen.plist is the off switch. The watcher only runs when launchd fires it; nothing is resident.

Install

imprnt plugin add kleinanzeigen

Copies the plugin into plugins/kleinanzeigen/ and wires @plugins/kleinanzeigen/agent.md into CLAUDE.local.md. Add per-listing fact sheets under listings/, then schedule (or run) the commands.

Remove

imprnt plugin rm kleinanzeigen           # unwire
imprnt plugin rm kleinanzeigen --purge   # unwire + delete plugins/kleinanzeigen/

Plus remove the launchd plist if you added one. Removal leaves no trace in the vault.

Building (contributors)

bun install
bun run build      # src/*.ts -> kleinanzeigen.js + check.js (node banner)
bun test           # 37 tests, incl. the real-inbox pipeline
bunx tsc --noEmit  # typecheck

Zero runtime dependencies. The fact-sheet parser, the rater, and the mirror reader are all hand-rolled to keep it dependency-free. License MIT.