Pi

pi (pi)

pi uses a managed Signet runtime extension installed by @signetai/connector-pi. The extension forwards lifecycle events to the daemon and injects hidden Signet context into the session when needed.

Files managed by Signet

File	Description
PI_CODING_AGENT_DIR/extensions/signet-pi.js	Managed extension bundle when PI_CODING_AGENT_DIR is set
~/.pi/agent/extensions/signet-pi.js	Managed extension bundle in the default pi agent directory

Managed extension

During setup or connect, the connector writes a bundled signet-pi.js file into the pi extensions directory. If PI_CODING_AGENT_DIR is set, Signet uses that agent directory. Otherwise it writes to ~/.pi/agent/extensions/.

Runtime behavior

• Existing unrelated pi extensions are left untouched.
• Signet refuses to overwrite a colliding unmanaged signet-pi.js.
• Daemon or network failures are fail-open, so prompt handling, compaction, session switches, and shutdown continue even if Signet is unavailable.
• Automatic recall: On every user prompt, the extension automatically fetches relevant memories from the daemon and injects them as hidden messages (display: false) into the agent’s context. These injections are kept out of transcript reconstruction.
• Manual commands: /recall <query> and /remember <content> let users explicitly search and store memories. The /recall command displays results in the UI only — it does not inject them into the conversation context. /signet-status shows connection and memory stats.
  • /remember <content> — save a memory
  • /remember critical: <content> — save as pinned (never decays)
  • /remember [tag1, tag2]: <content> — save with tags
  • /remember critical: [tag1, tag2]: <content> — pinned with tags (critical prefix must come first)
• Agent tools: signet_recall, signet_source_search, signet_session_search, and signet_remember are registered as LLM-callable tools. When the agent calls signet_recall, the results (including memory IDs) are returned into the conversation context via the tool response. signet_source_search searches provenance-backed artifacts separately from ordinary memory recall; signet_session_search searches active or completed session transcripts.
• Hidden inject messages use display: false and role: "custom". Pi converts custom messages to role: "user" for the LLM, so the X-Initiator header (which determines Copilot billing attribution) is set based on the last message’s role — extensions cannot override it via an attribution field as Oh My Pi can.
• Does not sync AGENTS.md into pi.

Configuration

Configuration is optional and loaded from ~/.pi/agent/extensions/signet.json (or $PI_CODING_AGENT_DIR/extensions/signet.json if set). The SIGNET_ENABLED environment variable overrides the file setting.

Optional ~/.pi/agent/extensions/signet.json:

{
  "enabled": false
}

Option	Description	Default
enabled	Whether Signet is enabled by default	true

Environment Variable (overrides file config):

Variable	Description
SIGNET_ENABLED	Set to false to disable

Examples:

# Use config file defaults
pi

# Disable Signet for a single session
SIGNET_ENABLED=false pi

# Create a config file to disable by default
echo '{"enabled": false}' > ~/.pi/agent/extensions/signet.json

Supported hooks

Hook	Supported
session-start	yes
user-prompt-submit	yes
pre-compaction	yes
compaction-complete	yes
session-end	yes

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