Module server 

Available on crate feature mcp and non-WebAssembly only.

The MCP service: the tool router, the shared argument types and the transport.

Each tool turns its JSON arguments into a McpCommand and sends it to the thread that owns the world. The tool then awaits the result: structured JSON for most tools, an image or audio content block for the ones that read pixels or samples back inline, and a written path for the ones that save to a file. A tool that fails returns a tool-level error result rather than a protocol error, so a model sees the message instead of a transport failure.

The router starts empty and the engine crates fill it in: a crate submits a ToolSource whose extend registers the tools that crate defines. The server therefore carries tools this crate knows nothing about, and a tool whose types live elsewhere still runs against the world through the same command channel.

Re-exports

use std::error::Error; 🔒

use std::future::Future; 🔒

use std::sync::Arc; 🔒

use rmcp::handler::server::tool::schema_for_input; 🔒

use rmcp::handler::server::wrapper::Parameters; 🔒

use rmcp::model::CallToolResponse; 🔒

use rmcp::model::CallToolResult; 🔒

use rmcp::model::ContentBlock; 🔒

use rmcp::model::ServerCapabilities; 🔒

use rmcp::model::ServerConfig; 🔒

use rmcp::model::Tool; 🔒

use rmcp::ErrorData; 🔒

use rmcp::ServerHandler; 🔒

use rmcp::tool_handler; 🔒

use schemars::JsonSchema; 🔒

use schemars::JsonSchema; 🔒

use serde::Deserialize; 🔒

use serde::Deserialize; 🔒

use serde::de::DeserializeOwned; 🔒

use serde_json::Value; 🔒

use crate::mcp::host::McpCommand; 🔒

use crate::mcp::host::Output; 🔒

use crate::mcp::host::WorldId; 🔒

use crate::Entity; 🔒

use crate::World; 🔒

Structs

ContextArg

Which world and render context a GPU tool runs against.

CreateMesh

Arguments for creating a mesh.

EntityArg

Arguments for one entity in a world.

GetComponent

Arguments for reading one component.

HandleArg

Which world and resource a handle tool runs against.

InputArg

Arguments for reading or sending input.

ListEntities

Arguments for listing entities.

LoadGltf

Arguments for load_gltf.

McpServer

The MCP server driving one or more worlds.

MeshTransform

A transform as JSON.

NoArgs

No arguments.

ReadBuffer

Arguments for reading a buffer.

RendererArg

Arguments for rendering a frame.

SaveBuffer

Arguments for saving a buffer to a file.

SaveScreenshot

Arguments for saving a screenshot as an image.

SaveTexture

Arguments for saving a texture as an image.

Screenshot

Arguments for taking a screenshot.

SendInput

Arguments for sending input events.

SetComponent

Arguments for writing one component.

SpawnEntity

Arguments for spawning an entity.

ToolRoute

ToolRouter

ToolSource

A crate’s contribution to the server’s tool set.

WorldArg

Which world a tool runs against.

Functions

command

Send a job to the world world names and await its JSON result.

default_limit 🔒

entity

An entity handle from the u64 bits a JSON argument carries.

identity4 🔒

one3 🔒

run

Send a job to the world world names and await its output.

send

Send a job to the world world names and await what it answered.

serve_stdio_with

Serve MCP over stdio, handing every command to sink.

serve_with

Serve MCP over any transport, handing every command to sink.

tool

A tool route from a name, a description and an asynchronous handler.

zero3 🔒

Type Aliases

CommandSender

The channel a tool sends its commands over.

ToolResult

What a tool handler answers with.