Headless Bitwarden (rbw) — Skill (addon)

Goal: safely retrieve secrets from Bitwarden without pasting passwords/tokens into chat.

This skill is intentionally small and non-overlapping:

• Use the existing Bitwarden skill for installation / account setup.
• This skill only adds an ephemeral remote unlock web helper for rbw.

This skill standardizes a workflow around:

• rbw (local encrypted cache + unlock)
• an ephemeral unlock web helper that you can start on-demand and shut down automatically.

Core rules (must)

1. Never paste secrets into chat

• No master password, no session keys, no JSON secrets.

2. Ephemeral by default

• Unlock helper must be localhost-only, token-gated, and auto-expire.
• Default TTL: 600s (10 minutes).

3. No secret logging / no secret persistence

• Do not log request bodies.
• Do not write secrets to disk.

4. Always restore rbw config

• If a temporary pinentry override is used, it must be restored even on failure.

Prereqs

1. Follow the workspace Bitwarden skill for setup (install, register/login):

• skills/bitwarden/SKILL.md

2. Additional requirements for the unlock helper:

• rbw installed and registered/logged-in (device approved)
• node available
• bash
• Optional (recommended for remote): cloudflared (for an ephemeral HTTPS URL)

Fast paths

A) If the vault is already unlocked

rbw unlocked
rbw sync
rbw search "\x3Ckeyword>"
rbw get "\x3Citem name>" --field "\x3Cfield name>"

B) If the vault is locked: start the ephemeral web unlock helper

From your workspace:

TTL_SECONDS=600 SYNC_AFTER_UNLOCK=1 \
  skills/headless-bitwarden/scripts/rbw-remote-unlock/start.sh

You will see:

• Local URL: http://127.0.0.1:\x3Cport>/\x3Ctoken>/
• If cloudflared exists: a Public URL: https://\x3Crandom>.../\x3Ctoken>/

Open the Public URL on your phone/laptop, enter the master password, and press Unlock. The helper will:

• run rbw unlock
• respond to the browser as soon as rbw unlock finishes
• optionally run rbw sync after the browser response (so the page shouldn’t spin)
• exit immediately on success (or auto-exit on TTL)

Security notes (residual risk, be explicit)

Even with HTTPS tunnel and no logs, this is not “zero risk”. Remaining risks include:

• password exists briefly in process memory
• password is passed briefly to a child process via env (in same-user scope)
• token URL leakage during TTL would allow access to the form
• tunnel provider is within the trust boundary (even though traffic is HTTPS)

Mitigations implemented:

• localhost bind only (127.0.0.1)
• high-entropy path token
• request body size limit
• no request-body logging
• TTL auto-exit + exit-on-success
• pinentry override always restored

Treat the Public URL as sensitive

The Public URL includes the one-time token. Anyone who obtains it during the TTL window can access the unlock form.

• Do not paste the Public URL into GitHub issues, logs, screenshots, or shared channels.
• Share it only to the person who is unlocking, and only for that one session.

Autofill note

The password input is configured to discourage browser/password-manager autofill (best-effort), but some managers may still try to fill. If you want to avoid accidental autofill, use a private/incognito window or temporarily disable the password manager for that page.

Retry / “unlock in progress” note

An unlock attempt can take a bit of time. If you submit twice quickly, you may see an “unlock attempt already in progress” message. Wait for the attempt to finish (default timeout is ~30s) before retrying.

Files

Implementation lives in:

• skills/headless-bitwarden/scripts/rbw-remote-unlock/{start.sh,server.mjs,pinentry.sh}

Troubleshooting / operational notes

pinentry restore reliability

The helper does not call rbw config set/unset (which can hang in non-interactive environments). Instead, it temporarily edits:

• ~/.config/rbw/config.json → pinentry: \x3Cpath-to-pinentry.sh>

and then restores it back.

If something crashes mid-flight, the quickest manual recovery is:

rbw config set pinentry pinentry

Agent state

If rbw unlocked says agent not running, restart/refresh the agent by running:

rbw stop-agent || true
rbw unlocked