⚒️ Modern MCP Forge

Build, test, and run MCP servers visually — without locking your tools to one language.

Local-first · Multi-project · Language-neutral · Git-friendly

Modern MCP Forge is a local-first visual workbench for authoring and testing Model Context Protocol servers. It keeps the MCP boundary standard while letting Tool implementations run through a small, language-neutral Forge Tool ABI.

The result is a developer environment where MCP Tools, Resources, and Prompts can be managed visually without requiring every Tool to be implemented in the same runtime.

✨ Highlights

Related MCP server: Photon MCP Server

🧭 How it fits together

flowchart LR
    HOST["AI client / IDE / Agent"] <-- "MCP<br/>Streamable HTTP or stdio" --> FORGE["⚒️ Modern MCP Forge"]

    FORGE --> TOOLS["🧰 Tools"]
    FORGE --> RESOURCES["📚 Resources"]
    FORGE --> PROMPTS["💬 Prompts"]

    TOOLS --> ABI["Forge Tool ABI"]
    ABI --> BUN["🟨 Bun"]
    ABI --> NODE["🟩 Node.js"]
    ABI --> PYTHON["🐍 Python"]

Forge speaks standard MCP externally. The Forge Tool ABI is an internal execution boundary that allows Tool implementations to remain runtime-independent.

🚀 Quick start

Requirements

• Bun — required

• Node.js — optional, for Node Tools

• Python — optional, for Python Tools

Install dependencies:

bun install

Run the development server:

bun run dev

Then open the local URL shown by Vite and create or open a Forge project.

Run the complete local release gate:

bun run test:all

🐳 Docker

Docker is also available as an optional distribution:

docker pull ghcr.io/modernsoftware/modern-mcp-forge:edge

For a persistent setup with host project folders mounted into Forge, use the included compose.yaml. See the Docker guide.

📦 Project model

A Forge project is intentionally portable:

my-mcp-project/
├── forge.project.json
├── tools/
├── resources/
└── prompts/

The project directory is the source of truth and can be committed directly to Git.

Machine-local state such as recent projects and execution history is kept outside the project in the user's application-data directory.

🔌 MCP transports

🌐 Streamable HTTP

With Forge running and a project open:

http://localhost:5173/mcp

Smoke test:

bun run mcp:smoke

🖥️ stdio

stdio launches Forge for one explicit project and does not depend on whichever project is open in the web UI:

bun run scripts/mcp-stdio.ts --project /path/to/forge-project

Smoke test:

bun run mcp:stdio:smoke -- --project /path/to/forge-project

This makes it suitable for MCP hosts that spawn local servers as child processes.

🧪 Quality and testing

Modern MCP Forge is tested at several levels:

Unit tests
    ↓
Integration tests
    ↓
HTTP + stdio MCP end-to-end tests
    ↓
Production build
    ↓
Windows + macOS + Linux GitHub Actions

Useful commands:

bun run check
bun run test:unit
bun run test:integration
bun run test:e2e
bun run test:coverage
bun run build
bun run test:all

The GitHub Actions workflow runs the verification suite on all three supported desktop operating-system families.

📚 Documentation

• 🗃️ Application data

• 🐳 Docker and GHCR

• 🖥️ MCP stdio transport

• 🧪 Testing

• 🔄 Continuous integration

• ✅ 0.9.0 release checklist

• 🤖 Agent example

• 📖 Documentation index

Additional documentation for architecture, the Tool ABI, security, troubleshooting, and contribution guidance will continue to grow during the public beta.

🔐 Security note

Local management endpoints are intentionally restricted to loopback traffic, and stdio reserves stdout exclusively for MCP protocol messages.

🤝 Contributors

Contributions, bug reports, ideas, and feedback are welcome.

See the contributors graph or open an issue.

📄 License

Modern MCP Forge is licensed under the Apache License 2.0.

Apache-2.0 is a permissive open-source license that allows commercial use, modification, and distribution while also providing an explicit patent grant.

Built by Modern Software

If Modern MCP Forge is useful to you, consider starring the repository and sharing feedback during the 0.9 public beta.