Agent MCP Studio – build multi-agent MCP systems in a browser tab

In plain words

Agent MCP Studio is a browser-based environment for building and running multi-agent systems using Model Context Protocol. It runs entirely from a single HTML file using WebAssembly, with no backend required. Users can author tools, orchestrate multiple agents, perform retrieval-augmented generation, and execute code—all in the browser with security enforced through WebAssembly sandboxing. The system supports LLM-generated tools with automatic validation, SQL execution via DuckDB, and on-device embeddings. It is designed for developers and researchers experimenting with agent systems who want a contained, offline-capable workspace.

written from the facts on this page · September 2026

From the sources

Build, run, and export MCP (Model Context Protocol) tools and AI agents entirely in your browser — no install, no server. Powered by Pyodide WASM & DuckDB-WASM. Free forever.

Pick a runtime, describe the tool in plain English, and the LLM will write the code. Each runtime has its own sandbox. A starter tool is pre-loaded — click Register Tool to try it immediately, no API key needed. Or generate code with an LLM above, then register it. Registration is metadata-only : the TOOL manifest is parsed via AST (zero code execution) and the source is stored. Python runs only when a tool is called — that's JIT. The LLM sees only the enabled tools. The export includes a production-ready Dockerfile + .dockerignore . After you download and unzip: cd agent-mcp-server-YYYY-MM-DD docker build -t agent-mcp-export . 2. Run (stdio — for local use with Claude Desktop) docker run…from agentmcp.studio

In the maker’s words, at launch

I built a browser-only studio for designing and orchestrating MCP agent systems for development and experimental purposes. The whole stack — tool authoring, multi-agent orchestration, RAG, code execution — runs from a single static HTML file via WebAssembly. No backend. The bet: WASM is a hard sandbox for free. When…

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