Lifeline

When your AI hits its limit, your work shouldn't.

v0.2.1 public beta — macOS is the primary supported platform. Native Windows, Linux, and WSL are beta-supported.

Lifeline runs Claude Code, Codex, or Gemini under protection. When the active AI hits its usage limit, Lifeline captures that exact session and opens another AI with the useful context already loaded.

lifeline codex
      │
      ├── Codex works normally
      │
      ├── Codex hits its usage limit
      │
      └── Lifeline opens Claude or Gemini with the same context

No re-explanation. No guessing which session you meant. The original session stays available.

Watch The Demo

See Lifeline detect an interrupted AI coding session, capture its context, and continue the work in another CLI.

https://github.com/user-attachments/assets/0ca13818-888b-4fa7-a208-780cca28b752

The video plays directly on GitHub; no download is required.

The Important Rule

Start the AI from a normal terminal using Lifeline:

lifeline codex

Do not launch plain codex and expect Lifeline to detect its limit. Lifeline can only automatically watch sessions that were started with lifeline claude, lifeline codex, or lifeline gemini.

Also, do not type lifeline switch ... into an AI chat prompt. Run manual switch commands from a second normal terminal window or tab.

Use Lifeline In Three Steps

1. Start a protected session

lifeline codex

Lifeline asks where it should hand the session over if Codex reaches its limit:

Start Codex under Lifeline protection.
When Codex hits its limit, switch to:
  1. Claude (default)
  2. Gemini
Choose [1-2] (default 1):

2. Work normally

Use Codex, Claude, or Gemini exactly as usual. Lifeline watches in the background and tracks the exact transcript belonging to this protected launch.

You should see:

⚡ Lifeline watching `codex` for usage limits (handoff target: claude)
   Protection active.

If that message was not shown when the AI started, the session is not protected.

3. Let Lifeline switch automatically

When Lifeline sees a real usage-limit message, it captures the exact protected session and opens the selected target with its context. The target starts in the captured project directory and remains protected, so a later limit can hand the work back again.

You can also switch before the limit. Open another normal terminal and run:

lifeline switch claude

Install And Run On Your Computer

macOS

Requirements: Python 3.9+, and at least two authenticated supported AI CLIs.

# Install Lifeline directly from GitHub
python3 -m pip install --user --upgrade git+https://github.com/AvnishR4j/lifeline.git

# Confirm your setup
lifeline doctor

# Start a protected AI session
lifeline codex

If lifeline is not found after installation, add your user Python scripts directory to PATH, then restart Terminal:

echo 'export PATH="$HOME/.local/bin:$HOME/Library/Python/3.9/bin:$PATH"' >> ~/.zshrc
source ~/.zshrc

On macOS, Lifeline opens the target in a new Terminal.app window while keeping the limited session open. The resumed target remains under Lifeline protection.

Windows

Use PowerShell or cmd. Python 3.9+ is required. Windows Terminal is recommended.

# Install or update to the latest GitHub version
py -m pip install --upgrade --force-reinstall git+https://github.com/AvnishR4j/lifeline.git

# Confirm the installed version and inspect the environment
lifeline version
lifeline doctor

# Start a protected session
lifeline codex

Native Windows automatically installs pywinpty for interactive ConPTY support. For immediate handoffs, Lifeline tries Windows Terminal, PowerShell, then cmd. Git Bash is best-effort.

Windows users upgrading from v0.2.0 should use the force-reinstall command above. v0.2.1 fixes native ConPTY keyboard input, supports current Gemini CLI launches without the removed --session-id argument, and tolerates Windows transcript encoding differences.

Linux

python3 -m pip install --user --upgrade git+https://github.com/AvnishR4j/lifeline.git
lifeline doctor
lifeline codex

On Linux, Lifeline watches the protected session and performs the handoff after the limited CLI exits.

WSL

Install and run Lifeline inside WSL using the Linux commands:

python3 -m pip install --user --upgrade git+https://github.com/AvnishR4j/lifeline.git
lifeline doctor
lifeline codex

WSL uses the Unix PTY backend. Native Windows and WSL sessions remain separate.

Supported AI Tools

Install and authenticate at least two:

All six directions are supported:

Claude → Codex     Claude → Gemini
Codex  → Claude    Codex  → Gemini
Gemini → Claude    Gemini → Codex

Commands You Will Use

# Start protected sessions
lifeline claude
lifeline codex
lifeline gemini

# Choose the fallback without being asked
lifeline codex --to gemini

# Switch a currently protected session from another terminal
lifeline switch claude

# Check installation, backends, CLIs, and transcript parsing
lifeline doctor

# Preview a manual handoff without launching the target
lifeline handoff --from codex --to gemini --dry-run

Other AI CLI arguments pass through:

lifeline claude --to gemini --model opus

The friendly launcher reserves --to for Lifeline. Put a literal underlying CLI --to option after --:

lifeline codex --to gemini -- --to some-codex-value

Why Did Lifeline Not Switch?

If the AI displays a usage limit but nothing happens:

1. Check whether the session was started with lifeline codex, lifeline claude, or lifeline gemini.
2. Look for the ⚡ Lifeline watching ... startup message.
3. Run lifeline doctor from a normal terminal.
4. If the session was started directly, use a manual handoff:

lifeline handoff --from codex --to claude

Manual lifeline switch only sees sessions started under Lifeline protection.

Advanced Usage

Use the full commands when you need an explicit source, target, dry run, or confirmation behavior:

lifeline watch --to gemini -- claude
lifeline watch --yes --to codex -- claude
lifeline watch --new-terminal --to codex -- claude
lifeline handoff --from codex --to gemini --dry-run
lifeline handoff --from codex --to gemini --session-file ~/.codex/sessions/...jsonl

Explicit --from is the most reliable bidirectional manual form:

lifeline handoff --from claude --to codex
lifeline handoff --from claude --to gemini
lifeline handoff --from codex --to claude
lifeline handoff --from codex --to gemini
lifeline handoff --from gemini --to claude
lifeline handoff --from gemini --to codex

# Auto-detect is convenient, but explicit --from avoids ambiguity:
lifeline handoff --to codex

# Preview what would be sent without launching anything:
lifeline handoff --from codex --to gemini --dry-run

Sources (capture from, via --from): claude, codex, gemini (default: auto). Targets (resume in, via --to): codex, gemini, claude. (Gemini uses gemini -i "<prompt>"; verify the flag against your installed @google/gemini-cli version.)

This will:

1. Resolve the selected source CLI session (Claude Code, Codex, or Gemini).
2. Extract the task, recent conversation, last prompt, and uncommitted git diff.
3. Redact secrets (see below) and warn you about what was scrubbed.
4. Write a secret-safe handoff file to ~/.lifeline/handoffs/.
5. Launch the target CLI seeded with that context, in the captured project directory and under continued Lifeline protection when the source CLI is still installed.

Diagnostics

lifeline doctor

doctor checks which supported CLIs are on PATH, whether each session root exists, whether the latest session for each source can be parsed, and prints the supported source→target matrix. Use it first if a specific direction such as Codex→Claude or Gemini→Codex is not working.

How it works

Security model

The handoff ships session content to another AI provider, so:

• Secret redaction — redact.py scans for OpenAI/GitHub/AWS/Google/Slack keys, common service tokens, JWTs, credentials embedded in URLs, Bearer tokens, PEM private keys, and .env-style secret assignments, and replaces them with [REDACTED:<kind>]. It runs locally (regex only, no network, no cost) and prints a summary of what was redacted before launch.
• Safe process launch — native executables receive argv lists directly. Windows npm .cmd shims are replaced with their PowerShell companions so handoff text stays data instead of being re-parsed by a batch shell. Lifeline rejects batch-only targets that cannot safely preserve arbitrary context.
• Private local storage — handoff files live under ~/.lifeline/handoffs/. Unix uses 0600 files in 0700 directories; Windows relies on the current user's profile-directory access controls.
• Path safety — --project-dir is validated to live under the selected source CLI's session root. Exact --session-file paths receive the same validation.
• Metadata-only active registry — live protected sessions are recorded under ~/.lifeline/active/ using 0700/0600 permissions. Records contain source, target, working directory, PID, session ID/path, and status; they do not copy transcript content.

Known limitations (v0)

• Beta support: native Windows, Linux, and WSL are public-beta platforms. PowerShell and cmd are tested on Windows; Git Bash is best-effort.
• Source coverage: Lifeline can capture from Claude Code, Codex, and Gemini — all three work as both source and target (e.g. Codex→Claude, Gemini→Claude). Other CLIs (Cursor, …) are not yet supported (see roadmap).
• Prompt injection: session content is wrapped and labeled as historical context, but a determined injection inside the session could still influence the resuming CLI. Acceptable for v0 since the session is your own.
• The redacted inline handoff may be temporarily visible to local process-list inspection tools while the target CLI starts.
• Manual lifeline switch only targets live sessions launched under Lifeline. Advanced lifeline handoff retains latest-session discovery for unprotected sessions, so use explicit --from and --session-file when exact selection is required there.
• Redaction is pattern-based; novel secret formats may slip through. Review the --dry-run output for anything sensitive before a real handoff.

Troubleshooting

Run lifeline doctor first. It reports the selected terminal backend, target CLI paths, session roots, parser health, and native Windows pywinpty availability.

On Windows, update with:

py -m pip install --upgrade --force-reinstall git+https://github.com/AvnishR4j/lifeline.git
lifeline version
lifeline doctor

Use this update if keyboard input crashes with a bytes ... PyString error, Gemini reports Unknown arguments: session-id, or ConPTY support is missing. If immediate handoff cannot open a new terminal, the generated handoff remains under ~/.lifeline/handoffs/ and the error includes the next action.

Uninstall with pipx uninstall lifeline or py -m pip uninstall lifeline.

Roadmap

• Any→any handoff. ✅ The source is pluggable via a sources.py registry and a --from flag, with claude, codex, and gemini readers all registered as launch targets — so any pair works (Codex→Claude, Gemini→Claude, …). The auto-detect wrapper (watch.py) recognizes all three CLIs' real limit messages and wires the wrapped CLI through as the capture source.
• More sources/targets: cursor, and others.