Module host 

Available on crate feature mcp and non-WebAssembly only.

The world side of the MCP server.

A World is not Send, and the work that reads it must happen on the thread that owns it. The MCP transport, on the other hand, runs on a tokio thread. The two meet at a command channel: a tool builds an McpCommand holding a closure and the WorldId of the world it should run against, the thread that owns that world resolves the id and calls McpCommand::dispatch, and the Output travels back on the command’s reply channel.

Nothing here assumes how many worlds there are or what a world contains. A crate that defines tools of its own submits a ToolSource and keeps its tool bodies next to the types they read; this module carries only the contract every tool shares.

Re-exports

use std::panic::AssertUnwindSafe; 🔒

use std::path::Path; 🔒

use schemars::JsonSchema; 🔒

use schemars::JsonSchema; 🔒

use serde::Deserialize; 🔒

use serde::Deserialize; 🔒

use serde_json::Value; 🔒

use crate::Entity; 🔒

use crate::World; 🔒

pub use crate::naming::extension_of;

pub use crate::naming::with_extension;

Structs

Despawned

What a despawn removed.

EncodedAudio

A sound the transport sends as an audio content block.

EncodedImage

An image the transport sends as an image content block.

McpCommand

A request together with the channel its result is sent back on.

SavedFile

A file a save tool wrote.

SpawnedEntity

A spawned entity, as the tools report it.

WorldEntry

One world a host reports, with the name it was spawned under.

Enums

Output

What a finished job produced.

Request 🔒

What a command asks the host to do.

WorldId

Which world a tool or a command runs against.

Functions

catch_job 🔒

Run one tool job, catching a panic into an error reply.

generated_name 🔒

The name a save writes when its caller named none: stem with a fresh random id, so a save never overwrites the file an earlier one wrote.

panic_message 🔒

The message a panic payload carries, with a fallback for foreign payloads.

saved_name

The name a save writes: the caller’s own, given extension when it carries none, or a fresh stem name when the caller named none.

to_value

Serialise a value through the reflection it derives.

write_file

Write bytes to directory/file_name, creating the directory.

Type Aliases

Job

A unit of work for the thread that owns a world.