MCP Server

MCP Sidecar MCP Server

Name: MCP Sidecar MCP Server
Author: io.github.lsequeiraa

io.github.lsequeiraa/mcp-sidecar

Repository Registry

What is the MCP Sidecar MCP server?

Cross-platform MCP server for managing long-lived background processes from any MCP client

How to install MCP Sidecar

Copy-paste configuration for popular MCP clients.

transport: stdio

Config generated by PluginBench — verify against the source before use.

Environment / auth

SIDECAR_MAX_PROCESSES
Maximum number of concurrent managed processes (default: 10)
SIDECAR_BUFFER_SIZE
Output buffer size per stream in bytes (default: 1048576)
SIDECAR_KILL_TIMEOUT
Milliseconds to wait between graceful and forced termination (default: 5000)
SIDECAR_CLEANUP_AFTER
Seconds before exited processes are auto-removed. 0 disables cleanup (default: 1800)
SIDECAR_MAX_OUTPUT_SIZE
Global cap on bytes returned by the output tool. 0 means unlimited (default: 0)
SIDECAR_ALLOWED_EXECUTABLES
Comma-separated allowlist of executable names. When set, enables security mode with direct exec (no shell). Unset means security disabled.
SIDECAR_BLOCKED_PATTERNS
Comma-separated regex patterns to reject in commands. Only applies when security is enabled.
SIDECAR_AUDIT_LOG
Audit log destination. 'true' writes to cwd, 'temp' writes to OS temp dir, or a directory path. Unset disables audit logging.

Claude Desktop

~/Library/Application Support/Claude/claude_desktop_config.json

{
  "mcpServers": {
    "mcp-sidecar": {
      "command": "npx",
      "args": [
        "-y",
        "mcp-sidecar"
      ],
      "env": {
        "SIDECAR_MAX_PROCESSES": "<YOUR_SIDECAR_MAX_PROCESSES>",
        "SIDECAR_BUFFER_SIZE": "<YOUR_SIDECAR_BUFFER_SIZE>",
        "SIDECAR_KILL_TIMEOUT": "<YOUR_SIDECAR_KILL_TIMEOUT>",
        "SIDECAR_CLEANUP_AFTER": "<YOUR_SIDECAR_CLEANUP_AFTER>",
        "SIDECAR_MAX_OUTPUT_SIZE": "<YOUR_SIDECAR_MAX_OUTPUT_SIZE>",
        "SIDECAR_ALLOWED_EXECUTABLES": "<YOUR_SIDECAR_ALLOWED_EXECUTABLES>",
        "SIDECAR_BLOCKED_PATTERNS": "<YOUR_SIDECAR_BLOCKED_PATTERNS>",
        "SIDECAR_AUDIT_LOG": "<YOUR_SIDECAR_AUDIT_LOG>"
      }
    }
  }
}

Cursor

~/.cursor/mcp.json

{
  "mcpServers": {
    "mcp-sidecar": {
      "command": "npx",
      "args": [
        "-y",
        "mcp-sidecar"
      ],
      "env": {
        "SIDECAR_MAX_PROCESSES": "<YOUR_SIDECAR_MAX_PROCESSES>",
        "SIDECAR_BUFFER_SIZE": "<YOUR_SIDECAR_BUFFER_SIZE>",
        "SIDECAR_KILL_TIMEOUT": "<YOUR_SIDECAR_KILL_TIMEOUT>",
        "SIDECAR_CLEANUP_AFTER": "<YOUR_SIDECAR_CLEANUP_AFTER>",
        "SIDECAR_MAX_OUTPUT_SIZE": "<YOUR_SIDECAR_MAX_OUTPUT_SIZE>",
        "SIDECAR_ALLOWED_EXECUTABLES": "<YOUR_SIDECAR_ALLOWED_EXECUTABLES>",
        "SIDECAR_BLOCKED_PATTERNS": "<YOUR_SIDECAR_BLOCKED_PATTERNS>",
        "SIDECAR_AUDIT_LOG": "<YOUR_SIDECAR_AUDIT_LOG>"
      }
    }
  }
}

Windsurf

~/.codeium/windsurf/mcp_config.json

{
  "mcpServers": {
    "mcp-sidecar": {
      "command": "npx",
      "args": [
        "-y",
        "mcp-sidecar"
      ],
      "env": {
        "SIDECAR_MAX_PROCESSES": "<YOUR_SIDECAR_MAX_PROCESSES>",
        "SIDECAR_BUFFER_SIZE": "<YOUR_SIDECAR_BUFFER_SIZE>",
        "SIDECAR_KILL_TIMEOUT": "<YOUR_SIDECAR_KILL_TIMEOUT>",
        "SIDECAR_CLEANUP_AFTER": "<YOUR_SIDECAR_CLEANUP_AFTER>",
        "SIDECAR_MAX_OUTPUT_SIZE": "<YOUR_SIDECAR_MAX_OUTPUT_SIZE>",
        "SIDECAR_ALLOWED_EXECUTABLES": "<YOUR_SIDECAR_ALLOWED_EXECUTABLES>",
        "SIDECAR_BLOCKED_PATTERNS": "<YOUR_SIDECAR_BLOCKED_PATTERNS>",
        "SIDECAR_AUDIT_LOG": "<YOUR_SIDECAR_AUDIT_LOG>"
      }
    }
  }
}

VS Code

.vscode/mcp.json

{
  "servers": {
    "mcp-sidecar": {
      "type": "stdio",
      "command": "npx",
      "args": [
        "-y",
        "mcp-sidecar"
      ],
      "env": {
        "SIDECAR_MAX_PROCESSES": "<YOUR_SIDECAR_MAX_PROCESSES>",
        "SIDECAR_BUFFER_SIZE": "<YOUR_SIDECAR_BUFFER_SIZE>",
        "SIDECAR_KILL_TIMEOUT": "<YOUR_SIDECAR_KILL_TIMEOUT>",
        "SIDECAR_CLEANUP_AFTER": "<YOUR_SIDECAR_CLEANUP_AFTER>",
        "SIDECAR_MAX_OUTPUT_SIZE": "<YOUR_SIDECAR_MAX_OUTPUT_SIZE>",
        "SIDECAR_ALLOWED_EXECUTABLES": "<YOUR_SIDECAR_ALLOWED_EXECUTABLES>",
        "SIDECAR_BLOCKED_PATTERNS": "<YOUR_SIDECAR_BLOCKED_PATTERNS>",
        "SIDECAR_AUDIT_LOG": "<YOUR_SIDECAR_AUDIT_LOG>"
      }
    }
  }
}

Claude Code

claude mcp add mcp-sidecar --env SIDECAR_MAX_PROCESSES=<YOUR_SIDECAR_MAX_PROCESSES> --env SIDECAR_BUFFER_SIZE=<YOUR_SIDECAR_BUFFER_SIZE> --env SIDECAR_KILL_TIMEOUT=<YOUR_SIDECAR_KILL_TIMEOUT> --env SIDECAR_CLEANUP_AFTER=<YOUR_SIDECAR_CLEANUP_AFTER> --env SIDECAR_MAX_OUTPUT_SIZE=<YOUR_SIDECAR_MAX_OUTPUT_SIZE> --env SIDECAR_ALLOWED_EXECUTABLES=<YOUR_SIDECAR_ALLOWED_EXECUTABLES> --env SIDECAR_BLOCKED_PATTERNS=<YOUR_SIDECAR_BLOCKED_PATTERNS> --env SIDECAR_AUDIT_LOG=<YOUR_SIDECAR_AUDIT_LOG> -- npx -y mcp-sidecar