Agentic bridge over MCP

Prism Server

A bridge that lets external tools — including MCP clients like Claude Code — operate on Prism files through stable, typed operations instead of raw text or fragile binary parsing.

A bridge to Prism files

prism-server is a bridge that lets external tools — including MCP clients like Claude Code — operate on Prism files through stable, typed operations, instead of raw text or fragile binary parsing. Point it at a document and it exposes that document over MCP (the Model Context Protocol) as a small set of typed tools an agent can call.

prism-server world.prisma

It is worth being precise about what this is and isn't. MCP is the transport — the standard way an assistant calls tools. Prism Server is not another MCP; it is the thing on the other end of one: a typed operation surface over a real structured file. It does not compete with Claude Code or replace your assistant. It gives them something to talk to.

The operations

The tools map directly onto the object model, so an agent reads and changes the file the same way a program would:

• read — describe, get_prim walk the tree;
• shape — define_prim, remove_prim, rename_prim change its structure;
• fill — set_property, set_metadata, connect, disconnect set the data and the links;
• files — load, save, search, compose, import, export move documents and formats around.

Why a typed bridge beats raw access

Hand an agent a bespoke binary file and it can only regenerate the whole thing and hope. Hand it raw text and every edit is a fragile guess at offsets. Prism removes both failure modes: because identity is a path and every datum is a typed value, "set /world/ball.radius to 2" is one set_property call — validated against the property's type, applied to the live document, rejected if it is ill-typed or structurally impossible.

This is the requirement that shaped the whole format: the property a human edits in a panel, a program sets through the API, and an agent changes over MCP are literally the same property, addressed and validated identically. The agent becomes a safe author, not a blunt regenerator — which is the entire point of giving it a structured file instead of a blob.

Prism all the way down

The server is Prism end to end: each request and response is itself a Prism document, the tool catalogue is built as a Document and encoded out, and the document being edited is a Document mutated through the same core everything else uses. It also reaches beyond a single file — search finds documents under a directory, compose flattens cross-file references, import/export route foreign formats through the codecs.

Embeddable — the live co-edit

The server's request handler is a plain function over a Document, so it does not have to own the process. The Prism Editor embeds the same handler behind a loopback endpoint: an external agent connects to the running editor, its typed operations are applied through the one mutation surface, and the panels redraw. You open a file, connect an agent, and watch it edit alongside you — the clearest demonstration of the bridge in action.