pulsar-mcp

Model Context Protocol server, that provides Pulsar editor tools to AI assistants.

Features

• MCP protocol: Version 2025-11-25 with tool annotations support.
• HTTP bridge: Server running inside Pulsar for direct API access.
• Standalone server: MCP server script for Claude CLI integration.
• Editor tools: Get/set content, open/save files, manage selections.
• Extensible: Other packages can register tools via mcp-tools service.
• Toggle tools: Enable/disable individual tools via select list. Destructive tools disabled by default.
• claude-chat integration: Auto-connects the MCP server to each Claude session via the provided service.

Installation

To install pulsar-mcp search for pulsar-mcp in the Install pane of the Pulsar settings or run ppm install pulsar-mcp. Alternatively, you can run ppm install asiloisad/pulsar-pulsar-mcp to install a package directly from the GitHub repository.

Commands

Commands available in atom-workspace:

• pulsar-mcp:toggle-tools: toggle individual tools on/off,
• pulsar-mcp:start: start the MCP bridge server,
• pulsar-mcp:stop: stop the MCP bridge server,
• pulsar-mcp:status: show current bridge status and port.

Commands available in .pulsar-mcp:

• select-list:enable-all: enable all tools,
• select-list:disable-all: disable all tools,
• select-list:reset-defaults: reset to defaults.

Built-in Tools

Tool	Description	Default
GetActiveEditor	Get editor metadata (path, grammar, modified, lineCount)	Enabled
GetOpenEditors	Get metadata for all open text editors	Enabled
ReadText	Read active editor content with line pagination (use agent's file tools for other files)	Enabled
WriteText	Write text at cursor or replace range in active editor (use agent's file tools for other files)	Enabled
OpenFile	Open an existing file in editor with optional position (create=true allows new files)	Enabled
SaveFile	Save a file (active editor or specific path)	Enabled
GetSelections	Get all selections/cursors with positions and text from active editor	Enabled
SetSelections	Set multiple selections/cursors at specific positions in active editor	Enabled
CloseFile	Close an editor tab	Disabled
GetProjectPaths	Get project root folders	Enabled
AddProjectPath	Add a folder to project roots	Enabled
RemoveProjectPath	Remove a folder from project roots	Disabled

MCP Client Integration

The standalone MCP server (lib/server.js) can be used with any MCP-compatible client. The server connects to the Pulsar bridge via PULSAR_BRIDGE_PORT (default 3000). Check the actual port with pulsar-mcp:status. It auto-increments when multiple Pulsar windows are open.

Claude Code

Register the server with the Claude CLI:

claude mcp add -e PULSAR_BRIDGE_PORT=3000 pulsar -- node ~/.pulsar/packages/pulsar-mcp/lib/server.js

On Windows:

claude mcp add -e PULSAR_BRIDGE_PORT=3000 pulsar -- node "%USERPROFILE%\.pulsar\packages\pulsar-mcp\lib\server.js"

JSON config

{
  "mcpServers": {
    "pulsar": {
      "command": "node",
      "args": ["~/.pulsar/packages/pulsar-mcp/lib/server.js"],
      "env": {
        "PULSAR_BRIDGE_PORT": "3000"
      }
    }
  }
}

On Windows, use "%USERPROFILE%\.pulsar\packages\pulsar-mcp\lib\server.js".

Provided Service pulsar-mcp

Provides access to the MCP bridge state: port, running status, and server script path. Used by claude-chat to auto-connect the MCP server.

In your package.json:

{
  "consumedServices": {
    "pulsar-mcp": {
      "versions": {
        "1.0.0": "consumePulsarMcp"
      }
    }
  }
}

In your main module:

consumePulsarMcp(service) {
  // Get current bridge port
  const port = service.getBridgePort();

  // Check if bridge is running
  const running = service.isRunning();

  // Get path to MCP server script
  const serverPath = service.getServerPath();
}

Consumed Service mcp-tools

Other Pulsar packages can provide additional MCP tools by implementing the mcp-tools service. Each tool defines a name, description, input schema, and execute function.

In your package.json:

{
  "providedServices": {
    "mcp-tools": {
      "versions": {
        "1.0.0": "provideMcpTools"
      }
    }
  }
}

In your main module:

module.exports = {
  provideMcpTools() {
    return [
      {
        name: "MyCustomTool",
        description: "Description for the AI",
        inputSchema: {
          type: "object",
          properties: {
            param: { type: "string", description: "Parameter description" }
          },
          required: ["param"]
        },
        annotations: { readOnlyHint: true },
        execute({ param }) {
          // Tool implementation
          return { result: "data" };
        }
      }
    ];
  }
}

Contributing

Got ideas to make this package better, found a bug, or want to help add new features? Just drop your thoughts on GitHub. Any feedback is welcome!