This adds codemode and MCP support to pi. Codemode (packages/codemode) runs
model-written JavaScript in a QuickJS wasm VM inside a worker. From there the
script calls pi's tools as async functions, uses a per-session store, and can
read the model catalog and run classifiers. The codemode tool in coding-agent
is compatible with Codex's exec tool, and codemode.mode works like Codex's
tool modes (on or only). Large results are written to a JSON temp file. MCP
(packages/mcp) is a standalone client for stdio and streamable HTTP servers,
with OAuth.
The core only gets general mechanisms; codemode, tool_search and MCP are
built-in extensions that use them. Other extensions can replace these
built-ins. Tools declare an exposure: direct, model-only, codemode, deferred
or hidden. prepareLoadout() lets an orchestrating tool change which tool
declarations the model sees. ctx.executeTool() runs nested calls through
validation and the tool_call/tool_result hooks. Those calls emit events with
parentToolCallId and are recorded as bounded nestedCalls on the parent
result, which compaction and HTML export use. Tools can also return
structuredContent with an outputSchema, and can report errors with isError
instead of throwing. MCP servers come from mcp.json (global, or per project
after the project is trusted) or from pi.registerMcpServer(). They are
managed with /mcp and pi mcp list|login|logout, and their runtimes load on
first use.
Closes#10040
A barrel forces Node to evaluate its whole graph: importing reduceLaneSnapshot
(1 file, 6 KB) through pi-agent-core's index evaluated 106 files, and mini's
server loaded 112 files to enumerate JSONL headers. Types are free, so this only
ever affected value imports.
pi-ai gains ./utils/* alongside the existing ./providers/* and ./api/*
wildcards. pi-agent-core gains ./harness/context, ./harness/env/nodejs,
./harness/runtime/reducer and ./harness/session, and ./session/testing becomes
./harness/session/testing so every export mirrors its source path. The barrel
and ./node keep their batteries-included semantics.
The session layer takes uuidv7 from @earendil-works/pi-ai/utils/uuid rather than
the pi-ai barrel, which is what let ./harness/session drop from 42 files to 19.
Two imports there were written `import { type Usage } from` - not a type-only
statement, so it emitted a runtime import of the barrel.
scripts/check-entry-graphs.mjs walks each declared entry's value-import graph and
enforces per-entry budgets and forbidden paths, so a stray `export *` cannot
silently undo this. It caught the two `import { type ... }` regressions above.
Measured with mini: server 112 files and 98 MB to 28 files and 69 MB, presentation
204 files and 125 MB to 99 files and 110 MB. The worker still loads the provider
graph, correctly.
