pi-print-stream

pi-print-stream

A Pi extension that adds a --stream CLI flag.

pi -p "your prompt here" --stream

Runs the turn non-interactively and streams it as it plays out — thinking deltas, text deltas, and tool activity — as plain text, with no TUI and no JSON envelope.

How it works — a wrapper over pi --mode json -p

--stream does not drive the turn itself. It intercepts the prompt and spawns a child pi --mode json -p "<prompt>" (inheriting your model/flags), pretty-prints the child's JSON event stream, and returns handled so Pi's own turn doesn't also run. The child uses Pi's real print-mode path, so prompt handling, the retry loop (429/5xx/empty/transient), and compaction are exactly what a normal pi -p run gets — no reimplemented (and subtly broken) turn lifecycle inside the extension.

Usage

pi -p "explain this repo" --stream      # recommended
pi --stream "explain this repo"         # also works (prompt recovered from argv)
echo "explain this repo" | pi --stream  # piped stdin
pi -p "..." --stream | less -R           # keep ANSI colors in a pager

Install

pi install npm:pi-print-stream

or, for local development:

pi -e ./src/extension.ts -p "your prompt" --stream

What you get

$ pi -p "What is 2+2? Think first." --stream

── thinking ──
The user wants 2+2. That's basic arithmetic: 4.

The answer is 4.

Tool calls are shown inline as they run:

→ read({"path":"/etc/hostname"})
← read done

Behavior notes

• Non-interactive only. The flag is active when there's no TUI — i.e. print mode (-p, or any run where stdout is not a TTY, such as a pipe or script). In interactive mode the TUI already renders the turn, so --stream is a no-op and the terminal is left untouched.
• No duplicated output. In plain print mode Pi normally echoes the final assistant text after the turn. Since --stream already streamed that text live, the extension strips the text blocks from the finalized message so it isn't printed twice. Tool calls and thinking in the transcript are left intact. Pass --no-session if you don't want the (text-trimmed) transcript persisted at all.
• JSON mode is untouched. Under --mode json Pi emits its own machine event stream and does no text echo, so --stream stays out of the way.

Colors

Thinking is dimmed, tool activity is cyan, answer text is default. Colors are ANSI escapes; pipe through a pager with -R (e.g. less -R) to preserve them, or they'll degrade gracefully to plain text in most capture contexts.

License

MIT