sidclaw-mcp-guard

sidclaw-mcp-guard

Stop AI agents from doing dangerous things through MCP.
Wraps any MCP server. Allows safe calls. Blocks dangerous ones. Holds the rest for you.

Get started

See it in action (30 seconds)

npx sidclaw-mcp-guard@latest demo

Set up a real guarded MCP server (2 minutes)

npx sidclaw-mcp-guard@latest quickstart

Creates a config, writes .mcp.json for Claude Code, and starts the approval dashboard.

Policy rules — no regex needed

Rules use semantic patterns — human-readable shortcuts instead of raw regex:

# sidclaw.config.yaml

rules:
  - name: allow-reads
    description: Read-only queries are safe
    match:
      pattern: sql-read           # SELECT, EXPLAIN, SHOW
    action: allow

  - name: approve-writes
    description: Data changes need approval
    match:
      pattern: sql-write          # INSERT, UPDATE, DELETE
    action: approve

  - name: deny-destructive
    description: Schema changes are never allowed
    match:
      pattern: sql-destructive    # DROP, TRUNCATE, ALTER, CREATE
    action: deny

default: deny

Available patterns: sql-read, sql-write, sql-destructive, file-read, file-write, file-delete, shell-safe, shell-risky, shell-destructive.

Note: In config, the action is called approve (what the user writes). In output, it displays as HOLD (describing the state of the call while waiting for human review).

Power users can still use regex via match.args — see docs/config.md.

Approve from your browser

Every guard instance can run a local approval dashboard:

sidclaw-mcp-guard --ui --upstream npx --upstream-args "..."

Open http://localhost:9091 — see pending requests, approve or deny with one click, inspect the audit trail.

Or use the CLI: npx sidclaw-mcp-guard approve <id>

Plain-English explanations

Every decision explains itself:

✔ ALLOW   SELECT * FROM users
  Allowed: read query on users. Read-only queries are safe.

⏳ HOLD    DELETE FROM users WHERE id = 42
  Held for approval: delete from users. Data changes need approval.

✘ BLOCK   DROP TABLE users
  Blocked: drop users. Schema changes are never allowed.

Explanations appear in the terminal, dashboard, and audit log.

Observe mode

Test your policies without blocking anything:

sidclaw-mcp-guard --observe --upstream npx --upstream-args "..."

The guard evaluates every call and logs what it would do, but forwards all calls regardless. Switch to enforce mode when ready.

Audit trail

Every decision is logged to .sidclaw/audit.jsonl:

{"timestamp":"...","tool":"query","args":{"sql":"SELECT * FROM users"},"decision":"allow","rule":"allow-reads","explanation":"Allowed: read query on users. Read-only queries are safe."}
{"timestamp":"...","tool":"query","args":{"sql":"DELETE FROM users WHERE id=42"},"decision":"approve","rule":"approve-writes","status":"approved","explanation":"Held for approval: delete from users. Data changes need approval."}
{"timestamp":"...","tool":"query","args":{"sql":"DROP TABLE users"},"decision":"deny","rule":"deny-destructive","explanation":"Blocked: drop users. Schema changes are never allowed."}

Works with any MCP server

Server	What you're guarding	Example config
@modelcontextprotocol/server-postgres	SQL queries	examples/sql-demo
@modelcontextprotocol/server-filesystem	File operations	examples/filesystem-demo
Shell-execution servers	Shell commands	examples/shell-demo
@modelcontextprotocol/server-github	Repo operations
Any custom MCP server	Any tool calls

CLI

# Get started
sidclaw-mcp-guard quickstart                   Set up a real guarded MCP server
sidclaw-mcp-guard demo                         Quick policy showcase
sidclaw-mcp-guard demo -i                      Interactive — try your own SQL

# Run
sidclaw-mcp-guard --upstream <cmd>             Start the guard proxy
sidclaw-mcp-guard --ui                         Start proxy + approval dashboard
sidclaw-mcp-guard --observe                    Observe mode (log only)

# Approvals
sidclaw-mcp-guard ui                           Open the approval dashboard
sidclaw-mcp-guard approve <id>                 Approve a pending request
sidclaw-mcp-guard deny <id>                    Deny a pending request
sidclaw-mcp-guard list                         List pending approvals
sidclaw-mcp-guard clean                        Remove stale approval files

Full Platform

SidClaw Guard is the local-first entry point to SidClaw. When you need more:

Need	SidClaw Guard (this)	SidClaw Platform
Policy rules	YAML with semantic patterns	Visual policy editor
Approvals	Local dashboard + CLI	Dashboard + Slack + Teams + Telegram
Audit trail	Local JSONL	Hash-chained, exportable, compliance-ready
Team workflows	Single user	Multi-reviewer, role-based access
Integrations	MCP servers	15+ SDKs (LangChain, Vercel AI, CrewAI...)

Learn more at sidclaw.com →

Docs

• Quick Start
• SQL Demo
• Config Reference
• How It Works
• FAQ

Development

git clone https://github.com/sidclawhq/mcp-guard.git
cd mcp-guard
npm install
npm run build
npm test

Run locally:

node dist/cli.js demo
node dist/cli.js quickstart

License

Apache 2.0