agent-bom-enforce — Runtime Policy Enforcement

Enforces security policies on MCP tool calls and blocks dangerous operations at runtime. Runs a local proxy that intercepts MCP calls and evaluates them against policy-as-code rules.

Install

pipx install agent-bom
agent-bom proxy              # start enforcement proxy
agent-bom policy apply policy.yaml  # apply a policy file
agent-bom policy check       # check current policy status

When to Use

• "block risky calls" / "block dangerous MCP calls"
• "apply policy" / "enforce policy"
• "proxy" / "MCP proxy"
• "runtime protection"
• "policy enforcement"
• "intercept MCP calls"

Commands

# Start the enforcement proxy
agent-bom proxy

# Apply a policy file
agent-bom policy apply policy.yaml

# Check current policy status
agent-bom policy check

Example Policy File

# policy.yaml
rules:
  - id: block-shell-exec
    description: Block shell execution tool calls
    match:
      tool: "bash|shell|exec|run_command"
    action: block
    severity: critical

  - id: require-path-allowlist
    description: Restrict filesystem access to allowed paths
    match:
      tool: "read_file|write_file|list_directory"
      args.path:
        not_starts_with: ["/home/", "/tmp/"]
    action: block
    severity: high

Guardrails

• IMPORTANT: Do not start the proxy or apply policies without explicit user confirmation — enforcement changes how MCP calls are processed.
• Confirm the policy file contents with the user before applying.
• Do not enable proxy mode autonomously — always ask the user first.
• Audit logs are written locally only; no data is transmitted externally.
• This skill has disable-model-invocation: true — do not auto-run enforcement actions.