MCP Server

The Expunct MCP server (@expunct/mcp) exposes all redaction capabilities as tools for Claude Code, Claude Desktop, and any MCP-compatible client.

Package: @expunct/mcp on npm

Quick Setup

Add the following to .mcp.json in your project root, or to ~/.claude/.mcp.json for global access:


{
  "mcpServers": {
    "expunct": {
      "command": "npx",
      "args": ["@expunct/mcp"],
      "env": {
        "EXPUNCT_API_KEY": "pk_live_...",
        "EXPUNCT_BASE_URL": "https://api.expunct.ai"
      }
    }
  }
}

For Claude Desktop, add the same configuration to ~/Library/Application Support/Claude/claude_desktop_config.json (macOS) or %APPDATA%\Claude\claude_desktop_config.json (Windows).

Configuration

Environment Variable	Required	Default	Description
`EXPUNCT_API_KEY`	Yes	—	API key (`pk_live_...` or `pk_test_...`)
`EXPUNCT_BASE_URL`	No	`https://api.expunct.ai`	API endpoint URL

Available Tools

Tool	Description	Sync
`expunct_sanitize_text`	Redact PII from text (27+ entity types)	Yes
`expunct_sanitize_file`	Submit file/URI for async redaction	No
`expunct_sanitize_batch`	Batch redact 1-100 URIs	No
`expunct_check_status`	Poll job progress	Read-only
`expunct_list_entity_types`	List all supported entity types	Read-only
`expunct_get_findings`	Get detected PII for a completed job	Read-only

Example Usage in Claude Code


> Redact PII from this text: "John Smith lives at 123 Main St"

Claude will use expunct_sanitize_text and return:
"[PERSON] lives at [ADDRESS]"

For file-based redaction, Claude will automatically use the async workflow — submitting the file with expunct_sanitize_file, then polling with expunct_check_status until the job completes.

Troubleshooting

“Tool not found” errors — Make sure the MCP server is running. Check npx @expunct/mcp runs without errors.
Authentication failures — Verify your API key starts with pk_live_ or pk_test_ and is valid.
Connection refused — If self-hosting, confirm EXPUNCT_BASE_URL points to your running instance.