@indexyz/pi-autocompact

Set an earlier automatic compaction threshold for the current model. The threshold is session-only unless you pass --save, which stores it as the user-level default for that model. Requires Pi 0.87.1 or newer (actionable session boundaries).

Install

pi install npm:@indexyz/pi-autocompact

Releases are published to npm as @indexyz/pi-autocompact; each release is tagged @indexyz/pi-autocompact@<version>.

To try a repository checkout (after npm install at the repository root):

pi -e ./pi-autocompact/index.ts

Usage

/autocompact 300k         # 300,000 tokens, current session/model only
/autocompact 0.3m         # same threshold; k/m are decimal units
/autocompact 300000
/autocompact 300k --save  # also store it as this model's user-level default
/autocompact --save 300k  # same as the line above
/autocompact              # show current threshold and native enabled state
/autocompact off          # use Pi defaults, ignoring plugin defaults in this session
/autocompact default      # clear the session override and inherit the global default

Without --save, commands never write settings. They also never append threshold entries to the session, reload extensions, or modify the model's real context-window metadata. --save is an error with off, default, a bare status query, or any extra argument; those forms leave the session and the file unchanged. Overrides are keyed by exact provider/modelId. Switching models preserves each model's session override. New, resumed, and forked sessions, restart, and /reload clear session overrides.

off does not disable Pi's own automatic compaction or overflow recovery.

Saved and manual defaults

--save merges the parsed token count into your user settings.json (normally ~/.pi/agent/settings.json, respecting PI_CODING_AGENT_DIR) at piAutocompact.modelLimits["provider/modelId"]. Other settings, including other model limits and native compaction settings, stay in place. Project .pi/settings.json is not written. You can still edit the same object by hand:

{
  "piAutocompact": {
    "modelLimits": {
      "provider/model-id": 300000
    }
  }
}

Values are positive integer token counts. The command that saved also applies the threshold to the current session, so that session does not need /reload. Each session start reads user settings again, so a later new, resumed, or forked session for that model uses the saved default with no further command. A hand edit made while a session is already running is picked up at the next session start; /reload is one way to start that fresh session. Plugin defaults are read only from user settings; trusted project settings still participate in native compaction configuration. A session command without --save overrides the saved value without changing the file.

Behavior and limitations

• Above the threshold, summarize at safe turn_end / agent_before_settle boundaries, after tools finish. Use Pi's standard summary generator and return a compaction entry through its boundary API; do not abort the agent or inject a synthetic user prompt. Normal tool/follow-up scheduling continues unchanged.
• Idle input also checks the threshold before submitting a prompt, using native ctx.compact() with its usual extension hooks.
• Boundary compaction preserves recent context according to the effective native keepRecentTokens, including complete assistant/tool-result groups. It uses the projected context so prior compactions and context edits are respected. The threshold must exceed keepRecentTokens and be below the real model window.
• Boundary summaries use the active registered provider and standard Pi summary generator; they do not invoke session_before_compact custom/native relay hooks. Pi's own auto/overflow/manual compaction remains untouched.
• Native compaction.enabled: false is respected. Enable it via /settings before setting a threshold. Plugin defaults load from user settings at each session start (including after /reload); native compaction settings are re-read when configuring or checking a threshold.
• Thresholds are not strict request-size caps: one turn/tool batch can overshoot. Unknown usage is skipped. If an indivisible or too-small context cannot retain recent content and shrink, the plugin leaves it to native/manual compaction.
• Summary generation consumes model tokens. Failures leave context intact and are not retried at the same session boundary. A subsequent turn can try again.

Development

npm run check
pi -e ./pi-autocompact/index.ts