system-prompt-switch

Pick, stack, edit, and forget — system prompts that follow you from Pi to OMP without re-explaining yourself.

A Pi / OMP extension that manages custom system prompts per session: interactive modals, cumulative stacking, two scopes (local repo + global home), CRUD commands, and an above-editor banner that always shows what's active.

Install

OMP

omp install npm:system-prompt-switch

PI

pi install npm:system-prompt-switch

That's it. The extension registers on next session start. Works in both Pi and OMP.

Screenshots

Startup session modal — pick a prompt or create one:

Editor banner while creating a new prompt (Ctrl+Q submit, Esc cancel):

Demo GIFs:

1. Select / Create system prompt when new session

2. Update system prompt (local or global)

3. Inject one or several system prompts for next message

4. Get information or logs

5. Delete a system prompt

What it does

• Per-session prompts — your active prompt is bound to the session ID, never leaks between concurrent or sequential sessions.
• Two scopes, one mental model — [local] lives in your repo (.agents/system-prompts-switch/, committable), [global] lives in your home (~/.pi or ~/.omp/agent/system-prompts-switch/). Same file can exist in both; local wins for the repo session.
• Stack multiple prompts — /sps-inject adds prompts cumulatively. [global] <system-prompt-name>.md + [local] project-rules.md is a valid active state.
• Above-editor banner — the active prompt is rendered directly above your input prompt so you never forget which one is loaded.
• Self-describing extension context — every resolved prompt includes a leading block that tells the LLM what this extension is, where prompt files live, and how to inspect/change them. The block is loaded from assets/templates/extension-context.md so you can tweak the wording without touching code.
• Startup modal — on terminal launch, pick (None), an existing prompt, or create one. Enabled by default; set promptOnStartup to false to skip it while retaining /sps-select and other commands:
  • OMP: ~/.omp/agent/config.yml

    systemPromptSwitch:
      promptOnStartup: false

  • Pi: ~/.pi/agent/extensions/system-prompt-switch.json

    { "promptOnStartup": false }

• Merge modes — append (default, safe) keeps base instructions; replace uses your prompt as the base while preserving tools, skills, and project context.
• Live logging to ~/.pi/agent/logs/system-prompt-switch.log / ~/.omp/agent/logs/system-prompt-switch.log, with /sps-logs [lines] inside the session.

Commands

How prompts live

Legacy prompts in ~/.pi/agent/system-prompts/ are auto-migrated on first run.

Reading the active prompt from another app

sessions.json is a public contract for clients (for example a chat UI driving omp over ACP): one entry per session ID, fields are only ever added.

{
  "<sessionId>": {
    "activePrompts": [{ "name": "reviewer.md", "scope": "global-omp" }],
    "mode": "append",
    "enabled": true,
    "decided": true
  }
}

scope is local, global-omp or global-pi; mode is append or replace. To change it, send /sps-select <name> or /sps-mode append|replace as a prompt in that session.

Over ACP the startup modal does not block: the client may send the first message before the user picks, so that message runs without the prompt. A client that picks the prompt itself starts the host with SPS_START_PICKER=0: no startup modal, then it sends /sps-select <name> before the first message. Unset (the default, e.g. the terminal) keeps the modal.

Editor shortcut note

When /sps-new or /sps-edit opens the built-in editor, an above-editor banner shows the real shortcuts: Ctrl+Q to submit, Esc to cancel. The host's footer also advertises Ctrl+Enter submit and Ctrl+G external editor — these are not wired by this extension; ignore them.

For developers

Architecture, build, test, and contribution guide: see README.dev.md.

License

MIT