p2 rewritten by the Chord v2 authoring rules (decision "App authoring rules confirmed
by the p2 audit"), in four parts merged together:
- core: session lifecycle (relocate, clone, fork, archive) and search rebuild are
persisted jobs on a new server store; Sessions v6 with client-chosen ids and visible
operations; Retry answers with the worker's real outcome; workers push branch,
subagent and status state to the server; roots take the method's ctx.
- services: models, envs, ports, login, mcp, logs, sharing and voice follow external
state (self.follow, followNative) instead of copy loops; methods answer after their
state commits; presence from host.references.
- chat: chat mode, artifacts and prompt resources follow Durable and native state;
shell commands are Chord jobs (shellId is the requestId); status pushed before
send and stop answer; race-free draft claim.
- ui: optimistic updates on web (useOptimistic) and terminal (TuiScope.optimistic,
extended in Chord with a reducer and a pending flag), pending states for long work,
visible rollback, load waterfalls removed; merged with the one composer and
immediate first send (ccff9876e) and the folder + button (5a31a6d5f).
docs/optimistic-ui.md describes the pattern.
- P2Tool: origin (any|owner) and scope (any|main|subagent) on the tool; the worker's
Durable registry checks them before each call (guardTool), no tool checks itself.
owner: location tools, reload_plugins, conversations, ports, MCP tools.
main: subagent, rename_session, conversations, ports, reload_plugins. subagent: team.
- originOf reads pi.live.run.inputs through tx.submission: the owner's only if every
input of the run is. Agent-written inputs record the writing turn's origin: subagent
tasks and one-shot prompts, team messages, reports (answerOrigin), peer messages.
No peer origin any more.
- Subagents and one-shot agents get their caller's tools (default all, tools narrows),
except scope main; with codemode the script-only tools; subagents get team. One-shot
agents keep codemode and agent. A send takes away what the caller can no longer give.
The agent drives the session's terminals (shared with the owner's panel) with
tools.terminal({ command, args }): new-window, list-windows, send-keys, read,
capture-pane, kill-window, with waits (quiet, exit, /regex/) and plain-text
output. The terminal host keeps each terminal's last MiB of output and the
agent's read cursor, answers calls with ids, and does keyed calls once, so the
tool is replay-safe. AgentTerminals serves the session's current worker on its
environments; archiving closes a session's terminals. Without code mode the
worker registry installs tool_search once for all deferred tools.
HTTP servers without an Authorization header sign in with OAuth: stored
tokens in mcp-auth.json, refreshed without a browser. /mcp/sign-in/<server>
returns to a loopback callback when the browser runs on the p2 host (the
device owner, or a relayed/public owner whose browser reaches a nonce probe
on 127.0.0.1), else to /mcp/callback on the origin p2 is reached through.
Pasting the final redirect URL always completes a waiting sign-in.
Web: an MCP sheet (status, restart, sign in/out, paste). TUI: /mcp and
/mcp paste. The sidebar footer's owner entries move into a More menu.
MCP tools are deferred and callable only by other tools, so code mode scripts call them and neither the model nor tool_search sees them. While code mode is off or its plugin is not loaded, tool_search loads them instead, as pi falls back. The mcp_servers prompt section, as pi's, names the servers and how their tools are reached.
A manager on the p2 server owns every MCP connection and process. Session
workers hold one view each and lease the locations their conversations
work at; the manager runs the owner's mcp.json servers there (stdio per
session and location, or shared; HTTP shared by default) and offers their
tools as deferred Durable tools found through tool_search.
Stdio servers on an environment start through its pi-env daemon, one
connection per environment shared by its instances, through cmd.exe on
Windows. A project's .pi/mcp.json, read by the worker at each location,
may add stdio servers that run there and switch the owner's servers on or
off; the manager refuses everything else. A lease gets servers only on
environments its session works on.