Agent-VC MCP Server

A specialized MCP server for AI agents to have persistent state, version control, and task management using Fossil SCM.

Why Agent-VC?

• Persistent State: Agents can store files in a structured, versioned workspace.
• Reproducibility: Full history of every commit, allowing rollbacks to any state.
• Task Management: Built-in tickets/tasks (via Fossil's ticket system) to track progress without external dependencies.
• Sandboxed: Operations are strictly limited to ~/.agent-vc/workspace/.

Structure & File Management

Core Directories

• ~/.agent-vc/: The root directory for all Agent-VC data and configuration.
• ~/.agent-vc/version_control.fossil: The Fossil repository file. This is a single SQLite database that stores your entire project history, version control objects, and task/ticket data.
• ~/.agent-vc/workspace/: The active checkout directory. All operations performed by the agent occur within this directory. This is the only place files are read from or written to.

File and Folder Mapping

Agent-VC uses a "Project" based organization within the shared workspace. This allows the agent to manage multiple logical projects or modules within a single version-controlled repository.

| Concept | Description | Path Example | | :--- | :--- | :--- | | Workspace Root | The base directory for all operations. | ~/.agent-vc/workspace/ | | Project Folder | A subdirectory representing a specific project. | ~/.agent-vc/workspace/chatbot-v1/ | | Project Subpath | A file or nested folder within a project. | ~/.agent-vc/workspace/chatbot-v1/src/utils.js |

Working with the MCP Tools

When using the agent-vc tools, you interact with files using the project and subPath parameters. This abstraction maps directly to the filesystem:

1. Initializing a Project: Running vc_init_project(name: "my-app") creates the directory ~/.agent-vc/workspace/my-app/.
2. Writing Files: Running write_file(project: "my-app", subPath: "main.py", content: "...") writes to ~/.agent-vc/workspace/my-app/main.py.
3. Nested Folders: You can use forward slashes in the subPath to create nested structures: write_file(project: "my-app", subPath: "docs/specs/readme.md", ...) will automatically create the docs/specs/ directories if they don't exist.

[!NOTE] All files created using the write_file tool are automatically added to Fossil's tracking (fossil add). To record these changes permanently in history, you must call vc_commit.

Installation

1. Install Fossil: Follow the official installation instructions on the Fossil website.

2. Run via npx: You can run the server directly using npx:

   npx agent-vc-mcp

3. Add to your MCP Config (e.g., claude_desktop_config.json or equivalent agent config):

{
  "mcpServers": {
    "agent-vc": {
      "command": "npx",
      "args": ["agent-vc-mcp"],
      "env": {
        "AGENT_VC_WORKSPACE": "/path/to/my/project",
        "AGENT_VC_FOSSIL_DB": "/path/to/backup.fossil"
      }
    }
  }
}

Environment Variables

You can tune Agent-VC behavior by setting these environment variables:

| Variable | Description | Default | | :--- | :--- | :--- | | AGENT_VC_ROOT_OVERRIDE | The root folder for agent data. | ~/.agent-vc/ | | AGENT_VC_WORKSPACE | Path to the workspace checkout. | ~/.agent-vc/workspace/ (if cwd is / or .) | | AGENT_VC_FOSSIL_DB | Path to the Fossil repository file. | ~/.agent-vc/version_control.fossil |

[!TIP] Setting AGENT_VC_WORKSPACE is useful if you want the agent to operate directly on an existing local directory that you've already initialized with Fossil SCM.

Tools

Version Control

• vc_init_project(name): Create a project subfolder.
• vc_commit(message): Commit all changes in the workspace.
• vc_status(): Get current status of tracking and changes.
• vc_diff(): View changes in the workspace.

File Operations (Project Scoped)

• write_file(project, subPath, content): Writes a file and automatically adds it to Fossil tracking.
• read_file(project, subPath): Reads a file.
• list_files(project): Lists all files in a project.

Task Management

• task_create(title, description): Create a project task.
• task_list(status?): List existing tasks.
• task_update(id, status, comment?): Update task status.

Usage Examples

🏢 Initializing a Project

Create a new project folder structure in the workspace.

{
  "name": "vc_init_project",
  "arguments": { "name": "chatbot-v1" }
}

💾 Writing and Committing Files

Write code and commit it to history.

// 1. Write the file
{
  "name": "write_file",
  "arguments": {
    "project": "chatbot-v1",
    "subPath": "index.js",
    "content": "console.log('Hello Agent!');"
  }
}

// 2. Commit the changes
{
  "name": "vc_commit",
  "arguments": { "message": "initial commit for chatbot" }
}

📋 Managing Tasks (Fossil Tickets)

Track work using the built-in ticket system.

// 1. Create a task
{
  "name": "task_create",
  "arguments": {
    "title": "Add streaming support",
    "description": "Implement chunked response parsing."
  }
}

// 2. List open tasks (to get the Ticket ID)
{
  "name": "task_list",
  "arguments": { "status": "Open" }
}

// 3. Update a task (using the first 7-10 characters of the Ticket ID)
{
  "name": "task_update",
  "arguments": {
    "id": "8d0aa38",
    "status": "Closed",
    "comment": "Work completed and tested."
  }
}

🔍 Inspecting Progress & History

// Check modified files
{ "name": "vc_status", "arguments": {} }

// View code diff
{ "name": "vc_diff", "arguments": {} }

// List all files in a project
{
  "name": "list_files",
  "arguments": { "project": "chatbot-v1" }
}

// Read a specific file
{
  "name": "read_file",
  "arguments": {
    "project": "chatbot-v1",
    "subPath": "index.js"
  }
}

Further Documentation

For more advanced Fossil commands and features (like branching, merging, and syncing), refer to the official Fossil SCM Documentation.