@lukeramsden/pi-prevent-stuck

A pi extension that keeps coding agents out of known shell traps: interactive editors, pagers, REPLs, terminal UIs, watch loops, prompt-only logins, and interactive git rebase.

Why

Agents run shell commands through a non-interactive tool boundary. Commands that wait for a full-screen UI, a pager, an editor, a password/login prompt, a REPL, or an interrupt can hang the run until a timeout.

What it blocks

Conservative default blocks include:

• Editors: vi, vim, nvim, nano, pico, emacs, emacsclient
• Pagers/help browsers: less, more, most, man, info
• TUIs and interrupt-only loops: top, htop, btop, watch, tmux, screen, fzf, peco
• REPLs when run without a script/command: python, python3, node, deno, bun; plus irb, pry, and php -a
• Interactive database/shell clients unless given a command/file/stdin: psql, mysql, mariadb, sqlite3, redis-cli
• Remote/file-transfer shells: ssh without a remote command, sftp, ftp
• Prompt-only Docker auth: docker login unless credentials are provided with --password-stdin or --password
• git rebase -i / git rebase --interactive unless GIT_SEQUENCE_EDITOR or git -c sequence.editor=... is set inline

Git hardening

For Git commands that are otherwise allowed, the extension prepends:

GIT_TERMINAL_PROMPT=0 GIT_PAGER=cat PAGER=cat GIT_EDITOR=: EDITOR=: VISUAL=:

This disables terminal credential prompts, Git pagers, and editor launches. Interactive rebase is still blocked unless you explicitly provide a non-interactive sequence editor.

Install

pi install npm:@lukeramsden/pi-prevent-stuck

Or try it for a single run:

pi -e npm:@lukeramsden/pi-prevent-stuck

Examples

Blocked:

git rebase -i HEAD~3
vim src/app.ts
less huge.log
docker login -u luke
ssh prod-box
watch npm test

Allowed or rewritten:

git log -n 20                 # rewritten with GIT_PAGER=cat
GIT_SEQUENCE_EDITOR=true git rebase -i --autosquash main
docker login --username foo --password-stdin < token.txt
python -c 'print("ok")'
psql -c 'select 1'
ssh prod-box 'uname -a'

Verify

npm run verify

Research notes

• Git documents --no-pager, GIT_PAGER=cat, GIT_EDITOR, GIT_ASKPASS, and GIT_TERMINAL_PROMPT=0 for non-interactive behavior.
• Git documents sequence.editor and GIT_SEQUENCE_EDITOR for git rebase -i todo editing.
• Docker documents docker login --password-stdin as the non-interactive login path.
• CircleCI documents that non-interactive shells can time out on prompts and pagers, and recommends disabling pagination such as with git --no-pager.

License

MIT