Pi coding agent adds MCP to its core after saying no to it
Earendil has folded Model Context Protocol support into the Pi agent's core, reversing its earlier public stance. Its post says MCP has improved but composes poorly, and pushes JavaScript Codemode instead.
Earendil, the company behind the Pi agent harness at pi.dev, published a post titled "You Said No MCP" announcing that Model Context Protocol support is now part of Pi's core. It had previously argued against MCP in public, and the post frames the change as a reversal. The post was on the Hacker News front page with 144 points and 57 comments when the paper read it this morning.
The team says it changed its mind because the world is not static and MCP has improved a great deal. It also says the work needed to bring MCP into the core, rather than leaving it as an optional extension, benefits Pi more broadly, including how it connects with Jev, the team's classifier system, according to the post.
Earendil says the underlying problem remains composability. It argues MCP should look much closer to OpenAPI, with intelligent tool discovery, structured data returned by tools and documentation an agent can find, rather than plain text responses. Those are the authors' views on where the protocol should go, not a change the protocol has made.
The alternative it promotes is Codemode, a JavaScript sandbox that runs on the trusted harness side. Earendil says agents can use it to orchestrate several tool calls at once and keep state through session transcripts instead of the filesystem. The post links pi.dev, an RFC site and the team's GitHub organisation.
The paper has not run the new build, and the post reports no benchmark comparing Codemode with plain MCP calls. Nobody outside Earendil has tested the claim that the integration helps beyond MCP itself, so the announcement rests on the maker's description of its own project.