pi-tui-history-replay

Keep Pi's visible transcript in chronological order across context compaction.

former turns  →  compaction summary  →  new turns

Pi still sends only its compacted context to the model. This extension repairs the interactive TUI replay path; it does not put old raw turns back into the LLM context.

Zero configuration. Zero runtime dependencies. TUI only.

Why

Context compaction and transcript display solve different problems:

• The model needs a smaller, compaction-aware context.
• The person at the terminal needs the conversation in the order it happened.

pi-tui-history-replay keeps those paths separate. It renders the full active session branch with Pi's native message and tool components while leaving SessionManager.buildSessionContext() untouched.

Install

Install from the Pi package catalog:

pi install npm:pi-tui-history-replay

Then start a new interactive session, or run /reload in the current one. There are no commands or settings to configure.

You can also install the current GitHub version:

pi install git:github.com/Molaison/pi-tui-history-replay

If you previously copied or symlinked tui-history-replay.ts into ~/.pi/agent/extensions/, remove that old installation before installing the package. Loading both copies would register the extension twice.

What changes

Path	Behavior
Interactive TUI transcript	Shows the full active branch in order
Compaction summary	Stays at its chronological position
Model context	Uses Pi's original compaction-aware context
Session storage	Adds no replay entries
Print, JSON, and RPC modes	Unchanged
Entries from older releases	Legacy replay entries are hidden

How it works

The extension installs a TUI-only in-memory patch when a session starts:

1. Transcript rebuilds read SessionManager.getBranch() instead of the compaction-pruned display entries.
2. When Pi emits session_compact, the persisted compaction entry is tracked.
3. Pi's live-compaction rebuild already appends a synthetic summary, so the persisted copy is omitted from that one rebuild to avoid a duplicate.
4. Later rebuilds use the complete branch, including the persisted summary.

The model-context method is never replaced. If Pi's compaction event and branch state disagree, the extension throws a visible error instead of silently rendering an incorrect transcript.

Compatibility

The extension depends on Pi's interactive transcript rebuild behavior.

Pi version	Status
0.80.6	Validated
0.81.1	Validated

Versions older than 0.80.6 and newer versions not listed above are untested. When reporting a compatibility issue, include the output of:

pi --version

Update and remove

Update the package with Pi:

pi update npm:pi-tui-history-replay

Remove it with:

pi remove npm:pi-tui-history-replay

Run /reload after updating or removing it from an active session.

Development

Requirements:

• Node.js 22.19.0 or newer
• Pi 0.80.6 or newer from the compatibility table

Install development dependencies and run the checks:

npm install
npm run check
npm pack --dry-run

Try the local extension without installing it:

pi --no-extensions -e ./tui-history-replay.ts

The regression tests cover:

• chronological active-branch replay;
• the one-rebuild live-compaction summary rule;
• non-TUI isolation;
• visible failure when the pending compaction entry is missing; and
• hiding legacy replay entries.

Security and scope

Pi extensions execute with the same system access as Pi. Review extension code before installing third-party packages.

This extension does not access the network, read or write project files, inject prompt text, or register model-callable tools. Its runtime work is limited to Pi session events and the in-memory TUI transcript builder.

License

MIT © Molaison