Demo

https://github.com/user-attachments/assets/8a40565a-fcdd-47bf-ae67-bc870611c908

Packages & Entry Points

| Module | Role | Status | Links | |--------|------|--------|-------| | cesium-mcp-contracts | Transport-neutral names, descriptions, and JSON Schemas for browser tools | New shared layer | source | | cesium-mcp-bridge | Protocol- and transport-free Cesium command executor (60+ commands) | Mainline, actively iterated | · source | | cesium-mcp-webmcp | Native document.modelContext adapter for Cesium tool contracts | New browser adapter | source | | examples/webmcp-integration | Focused npm + Vite integration without a chat UI or MCP server | Developer example | example | | examples/browser-agent | Browser-only AI agent with automatic WebMCP exposure | Recommended | example · live demo | | cesium-mcp-runtime | MCP server (stdio + HTTP) | Stable MCP SDK v2 | · source | | cesium-mcp-dev | CesiumJS API knowledge base for coding assistants | Maintained | · source |

Which one? Personal project or quick try → browser-agent. Let a compatible browser agent discover page-local Cesium tools → WebMCP. Existing web app embedding an AI assistant → bridge + your own function calling. Calling from Claude Desktop / Cursor / Dify → MCP runtime.

Architecture

flowchart LR
  subgraph clients ["AI Drivers (pick one)"]
    BA["Browser Agent\n(in the same page)"]
    WM["WebMCP Agent\n(browser-provided)"]
    FC["Your web app\nfunction calling"]
    MCP["Claude / Cursor / Dify\nvia MCP runtime"]
  end
CONTRACTS["cesium-mcp-contracts\ntool definitions"]   WEBMCP["cesium-mcp-webmcp\nnative adapter"]
subgraph core ["cesium-mcp-bridge (browser)"]     B["60+ tools\nprotocol-agnostic dispatcher"]     C["CesiumJS Viewer"]   end
CONTRACTS -.-> BA   CONTRACTS -.-> WEBMCP   BA -- "in-page call" --> B   WM -- "document.modelContext" --> WEBMCP   WEBMCP --> B   FC -- "in-page call" --> B   MCP -- "WebSocket / JSON-RPC" --> B   B --> C
style clients fill:#1e293b,stroke:#528bff,color:#e2e8f0   style core fill:#1e293b,stroke:#12B76A,color:#e2e8f0

The bridge remains the execution core, while contracts and protocol adapters stay separate. Pick whichever driver matches your scenario — they all reach the same Cesium command layer. On WebMCP-capable browsers, cesium-mcp-webmcp can expose 61 browser-safe commands in 12 selectable toolsets through document.modelContext without adding an MCP transport or backend server.

Quick Start

Path 0 — Try in 30 seconds (browser agent, recommended)

Open the live demo and ask—the hosted model is ready without a browser API key:

"Fly to the Eiffel Tower and drop a red marker"

Fork the examples/browser-agent folder to deploy your own.

Path 1 — Expose Cesium tools through WebMCP (Chrome 149+ experimental)

The browser-agent example automatically registers all 61 browser-safe page tools when document.modelContext is available. Its built-in chat uses automatic toolset routing to keep each normal request at 20 tools or fewer, while still offering explicit core, single-toolset, and all-61 modes:

npm run build -w packages/cesium-mcp-bridge
npm run build -w packages/cesium-mcp-webmcp
npx serve . -l 4173

Open http://localhost:4173/examples/browser-agent/, click Start, then inspect or execute the tools in DevTools → Application → WebMCP. Enable #enable-webmcp-testing and #devtools-webmcp-support in chrome://flags for local testing.

Application developers install the adapter separately. End users only open the integrated website; they do not install npm packages or run an MCP server.

npm install cesium cesium-mcp-bridge cesium-mcp-webmcp

import { CesiumBridge } from 'cesium-mcp-bridge'
import { registerCesiumWebMcp } from 'cesium-mcp-webmcp'
const bridge = new CesiumBridge(viewer) const registration = await registerCesiumWebMcp(bridge, {   toolsets: 'all',   excludeTools: ['geocode'], // add your own browser geocoder to expose this tool })
// Later, if the page is unmounted: registration.unregister()

See the WebMCP adapter API for custom integrations. For a complete npm + Vite application, start from the WebMCP integration example.

Path 2 — Embed in your own web app (function calling)

npm install cesium-mcp-bridge

import { CesiumBridge } from 'cesium-mcp-bridge';
const bridge = new CesiumBridge(viewer); // Then: send the bridge's tool schema to any LLM that supports function/tool calling, // route the model's tool calls to bridge.execute(name, params).

See examples/browser-agent/index.html for a complete loop with OpenAI-compatible APIs.

Path 3 — Use from Claude Desktop / Cursor / Dify (MCP)

Install bridge as in Path 2, then start the MCP runtime:

# Stable channel — npm latest, MCP SDK v2
npx cesium-mcp-runtime
HTTP mode
npx cesium-mcp-runtime --transport http --port 3000

The stable release serves existing MCP 2025-11-25 clients and the new 2026-07-28 protocol from the same stdio/HTTP entry. It uses the stable TypeScript SDK v2 and passes the official server-stateless conformance scenario (28/28).

MCP client config:

{
  "mcpServers": {
    "cesium": {
      "command": "npx",
      "args": ["-y", "cesium-mcp-runtime"]
    }
  }
}

62 Available Command Tools

Tools are organized into 12 toolsets. Default mode enables 4 core toolsets (30 tools). Set CESIUM_TOOLSETS=all for everything, or let the AI discover and activate toolsets dynamically at runtime.

Canonical contracts: Tool descriptions default to English; set CESIUM_LOCALE=zh-CN for Chinese. Titles, behavior annotations, localized descriptions, defaults, and Runtime input validation all come from the shared JSON Schemas in cesium-mcp-contracts.

| Toolset | Tools | |---------|-------| | view (default) | flyTo, setView, getView, zoomToExtent, saveViewpoint, loadViewpoint, listViewpoints, exportScene | | entity (default) | addMarker, addLabel, addModel, addPolygon, addPolyline, updateEntity, removeEntity, batchAddEntities, queryEntities, getEntityProperties | | layer (default) | addGeoJsonLayer, addGeoJsonPrimitive, listLayers, removeLayer, clearAll, setLayerVisibility, updateLayerStyle, getLayerSchema, setBasemap | | interaction (default) | screenshot, highlight, measure | | camera | lookAtTransform, startOrbit, stopOrbit, setCameraOptions | | entity-ext | addBillboard, addBox, addCorridor, addCylinder, addEllipse, addRectangle, addWall | | animation | createAnimation, controlAnimation, removeAnimation, listAnimations, updateAnimationPath, trackEntity, controlClock, setGlobeLighting | | tiles | load3dTiles, load3dGaussianSplat, loadTerrain, loadImageryService, loadCzml, loadKml, setEdgeDisplayMode | | trajectory | playTrajectory | | heatmap | addHeatmap | | scene | setSceneOptions, setPostProcess, setIonToken (Runtime only) | | geolocation | geocode |

Relationship with CesiumGS official MCP servers: The camera, entity-ext, and animation toolsets natively fuse capabilities from CesiumGS/cesium-mcp-server (Camera Server, Entity Server, Animation Server) into this project's unified bridge architecture. This means you get all official functionality plus additional tools — in a single MCP server, without running multiple processes.

Examples

See examples/minimal/ for a complete working demo.

Development

git clone https://github.com/gaopengbin/cesium-mcp.git
cd cesium-mcp
npm install
npm run build
npm test
npm run test:contracts

test:contracts is the focused parity gate for MCP Runtime metadata, WebMCP registration, Function Calling definitions, and the 60-tool Bridge Executor Registry.

Version Policy

Version format: {CesiumMajor}.{CesiumMinor}.{MCPPatch}

| Segment | Meaning | Example | |---------|---------|--------| | 1.143 | Tracks CesiumJS version — built & tested against Cesium ~1.143.0 | 1.143.0 → Cesium 1.143 | | .x | MCP patch — independent iterations for new tools, bug fixes, docs | 1.143.0 → 1.143.1 |

Official CesiumJS releases are reviewed before the compatibility baseline is bumped; the project does not automatically claim support for a newer release without Bridge verification.

Related Projects

• mapbox-mcp — AI control for Mapbox GL JS
• openlayers-mcp — AI control for OpenLayers

Star History

License

MIT