MCP Integration

Rafter runs as a standard MCP server over stdio, exposing security tools to any MCP-compatible client—Cursor, Windsurf, Claude Desktop, Cline, and others. No API key required. All tools run locally.

Setup

1. Install Rafter CLI

npm install -g @rafter-security/cli

pnpm add -g @rafter-security/cli

pip install rafter-cli

2. Add to Your MCP Client

Add Rafter to your MCP client’s server configuration:

// ~/Library/Application Support/Claude/claude_desktop_config.json
{
  "mcpServers": {
    "rafter": {
      "command": "rafter",
      "args": ["mcp", "serve"]
    }
  }
}

// .cursor/mcp.json
{
  "mcpServers": {
    "rafter": {
      "command": "rafter",
      "args": ["mcp", "serve"]
    }
  }
}

Cursor users hitting a sandbox prompt: prefer the per-project install — rafter agent init --local --with-cursor — which writes to ./.rafter/ and ./.cursor/ instead of $HOME. Global install (rafter agent init --with-cursor) requires elevated permissions if Cursor’s sandbox restricts writes to your home directory.

// ~/.codeium/windsurf/mcp_config.json
{
  "mcpServers": {
    "rafter": {
      "command": "rafter",
      "args": ["mcp", "serve"]
    }
  }
}

{
  "rafter": {
    "command": "rafter",
    "args": ["mcp", "serve"]
  }
}

3. Restart Your Client

Restart the MCP client to load Rafter’s tools. You should see eight tools and two resources available: the four local, read-only tools described below, plus the four remote Sites tools (the Sites tools work without further setup if RAFTER_API_KEY is set, but only calls to them require a key — the local tools never do).

Tools

Rafter exposes four read-only security tools over MCP.

`scan_secrets`

Scan files or directories for hardcoded secrets and credentials.

Parameter	Type	Required	Description
`path`	string	Yes	File or directory path to scan
`engine`	string	No	`auto` (default), `betterleaks`, or `patterns`

Returns an array of scan results with file paths, pattern names, severity levels, and redacted matches.

Example Response

[
  {
    "file": "src/config.ts",
    "matches": [
      {
        "pattern": "AWS Access Key",
        "severity": "critical",
        "line": 12,
        "redacted": "AKIA****"
      }
    ]
  }
]

`evaluate_command`

Evaluate whether a shell command is allowed by Rafter security policy.

Parameter	Type	Required	Description
`command`	string	Yes	Shell command to evaluate

Returns whether the command is allowed, its risk level, and whether it requires approval.

Example Response

{
  "allowed": false,
  "risk_level": "critical",
  "requires_approval": false,
  "reason": "Matches blocked pattern: rm -rf /"
}

`read_audit_log`

Read Rafter audit log entries with optional filtering.

Parameter	Type	Required	Description
`limit`	number	No	Maximum entries to return (default: 20)
`event_type`	string	No	Filter: `command_intercepted`, `secret_detected`, `content_sanitized`, `policy_override`
`since`	string	No	ISO 8601 timestamp — only entries after this time

`get_config`

Read Rafter configuration (full config or a specific key).

Parameter	Type	Required	Description
`key`	string	No	Dot-path config key (e.g. `agent.commandPolicy`). Omit for full config.

Resources

Two read-only resources expose Rafter’s current state.

URI	Description
`rafter://config`	Current Rafter configuration (JSON)
`rafter://policy`	Active security policy — merged `.rafter.yml` + `~/.rafter/config.json` (JSON)

How It Works

The MCP server wraps Rafter’s existing CLI classes:

scan_secrets uses RegexScanner (built-in 21+ patterns) with automatic fallback from Betterleaks (v0.8.0+; gitleaks successor)
evaluate_command uses CommandInterceptor with policy-driven risk assessment
read_audit_log reads from ~/.rafter/audit.jsonl
get_config reads from ~/.rafter/config.json merged with .rafter.yml

All tools are read-only. Configuration changes go through the CLI (rafter agent config set).

Configuration

The MCP server uses the same configuration as all other Rafter commands. Set up your security policy once and it applies everywhere:

# Initialize Rafter (creates ~/.rafter/config.json)
rafter agent init

# Customize policy
rafter agent config set agent.riskLevel moderate
rafter agent config set agent.commandPolicy.mode approve-dangerous

Or use a .rafter.yml policy file in your project root. See Policy File for details.

Verify Installation

After adding Rafter to your MCP client, test that tools are working:

Ask the agent to scan a directory for secrets
Ask it to evaluate whether rm -rf / is safe
Ask it to show your Rafter configuration

If the agent can call these tools, Rafter is connected.

Sites Tools (Remote, API-Key-Gated)

The four tools above are local-only, read-only, and require no API key. Rafter also exposes a separate set of Sites tools that are the opposite on every axis: they call Rafter’s remote API, require an API key, and two of them mutate state (create a site, trigger a scan).

Sites tools are not part of the “four tools” described above — they are a distinct surface for live-application security monitoring, not local secret scanning or command policy.

	Local Tools (above)	Sites Tools (below)
Where it runs	Locally, on your machine	Rafter’s remote API
API key	Not required	Required (`x-api-key`, scope `read` or `read-and-scan`)
Mutates state	No — all read-only	`sites_create` and `sites_scan` do

Authentication

The Sites tools resolve your API key the same way the CLI does: the RAFTER_API_KEY environment variable, or your stored Rafter config, checked in that order.

`sites_create`

Parameter	Type	Required	Description
`url`	string	Yes	The URL of the site to monitor

`sites_scan`

Trigger a re-scan of a site you already own. Requires an API key with the read-and-scan scope.

Parameter	Type	Required	Description
`projectId`	string	One of `projectId`/`url`	The site’s id
`url`	string	One of `projectId`/`url`	The site’s URL
`sections`	array of strings	No	Restrict the scan to `"flight"`, `"security"`, and/or `"dns"`

`sites_list`

List your sites, paginated. Requires an API key with the read scope.

Parameter	Type	Required	Description
`limit`	number	No	Number of sites to return, `1`-`100` (default `25`)
`offset`	number	No	Number of sites to skip (default `0`)
`include_archived`	boolean	No	Include archived sites (default excludes them)

`sites_get`

Get a site’s status, latest run, and findings summary. Requires an API key with the read scope.

Parameter	Type	Required	Description
`id`	string	Yes	The site’s id

See the Sites API reference for full request/response shapes, and the Sites CLI guide for the equivalent rafter sites commands.

Compared to Pretool Hooks

	MCP Server	Pretool Hooks
Platform	Any MCP client	Claude Code only
Model	Agent calls tools explicitly	Hooks intercept before every tool call
Trust	Agent chooses to use tools	Agent cannot bypass hooks
Setup	Add to MCP config	`rafter agent init --with-claude-code`

For maximum security on Claude Code, use both: pretool hooks for enforcement + MCP tools for agent-initiated scans. For other platforms, the MCP server is the primary integration path.

What’s Next?

Secret Scanning

21+ secret patterns detected

Policy File

Define per-project security policies

Command Reference

Full CLI reference

Get Started

CLI Guides

Local Security

References

MCP Integration

MCP Integration

Setup

1. Install Rafter CLI

2. Add to Your MCP Client

3. Restart Your Client

Tools

`scan_secrets`

`evaluate_command`

`read_audit_log`

`get_config`

Resources

How It Works

Configuration

Verify Installation

Sites Tools (Remote, API-Key-Gated)

Authentication

`sites_create`

`sites_scan`

`sites_list`

`sites_get`

Compared to Pretool Hooks

What’s Next?

Secret Scanning

Policy File

Command Reference

​MCP Integration

​Setup

​1. Install Rafter CLI

​2. Add to Your MCP Client

​3. Restart Your Client

​Tools

​scan_secrets

​evaluate_command

​read_audit_log

​get_config

​Resources

​How It Works

​Configuration

​Verify Installation

​Sites Tools (Remote, API-Key-Gated)

​Authentication

​sites_create

​sites_scan

​sites_list

​sites_get

​Compared to Pretool Hooks

​What’s Next?

Secret Scanning

Policy File

Command Reference

MCP Integration

Setup

1. Install Rafter CLI

2. Add to Your MCP Client

3. Restart Your Client

Tools

`scan_secrets`

`evaluate_command`

`read_audit_log`

`get_config`

Resources

How It Works

Configuration

Verify Installation

Sites Tools (Remote, API-Key-Gated)

Authentication

`sites_create`

`sites_scan`

`sites_list`

`sites_get`

Compared to Pretool Hooks

What’s Next?