AgentsGate

Undo for AI agents. A local proxy that snapshots what your coding agent is about to touch, so a bad edit or a wrong DELETE is one command away from being undone — and stops the things that no snapshot can bring back.

Status: 0.2.0. Covered by 7,431 tests, but treat the API surface as unstable until 1.0 — command flags and config keys may still change.

What it undoes, and what it stops instead

Not everything can be undone, so AgentsGate does two different jobs.

That split is the design. Where a checkpoint can put things back, AgentsGate gets out of the way and lets the agent work. Where nothing can, it asks you first — which is why rm -rf waits for a yes while deleting one file does not.

Related MCP server: Nervora

Scope — what this is not

AgentsGate is a local, single-operator tool: it protects you from your own agent on your own machine. It is not a network security boundary, not a multi-tenant gateway, and not an authentication layer. The proxy transport has no authentication at all, which is safe only because everything binds to loopback by default. If you move it off loopback, that is on you — see Security model below.

Try it in thirty seconds

Watch it refuse to overwrite a credential file, without installing anything or touching your Claude Desktop config:

mkdir -p /tmp/agentsgate-demo && cd /tmp/agentsgate-demo && echo 'SECRET=keep-me' > .env

CALL='{"jsonrpc":"2.0","id":1,"method":"tools/call","params":{"name":"write_file","arguments":{"path":"'"$PWD"'/.env","content":"HACKED"}}}'

printf '%s\n' "$CALL" \
  | npx -y agentsgate proxy -- npx -y @modelcontextprotocol/server-filesystem "$PWD"

[agentsgate] BLOCK  90%  write_file

{"error":{"message":"AgentsGate blocked: Risk score 0.90 meets or exceeds block threshold (0.7)",
          "data":{"riskScore":0.9,"reasons":["Triggered rule: L1_SENSITIVE_PATH_WRITE", ...]}}}

Your .env is untouched. To see what else is stopped, and why:

npx -y agentsgate level

Then wire up your agent for real:

npm install -g agentsgate      # inject writes `agentsgate` into the MCP config,
agentsgate inject              # so this step needs a global install
agentsgate start               # proxy on 4000, dashboard on 4001

How a decision is made

Two stages. The protection level is one broad setting covering every kind of operation — agentsgate level shows what it stops and why. Policy rules are your exceptions on top, and can tighten or loosen it. Everything is logged either way, and anything risky is checkpointed first.

Security model — read this first

AgentsGate is a local, single-operator tool. It records everything your agent does, including tool arguments and results that routinely contain file contents, database rows, and credentials.

The proxy transport has no authentication, and the dashboard's is opt-in. That is safe only because AgentsGate binds to loopback by default:

proxy.host controls the bind address for the proxy, dashboard, and WebSocket gateway. Leave it at 127.0.0.1 unless you know exactly what you are doing.

If you set proxy.host to a routable address, you must put an authenticating reverse proxy in front of it. No AgentsGate setting alone makes a non-loopback bind safe — exposing it without a reverse proxy means unauthenticated operation forwarding plus full read access to your agent's history. AgentsGate prints a startup warning when you do this; treat it as an error in production.

For the full threat model, residual risks, and a deployment checklist, see SECURITY.md.

Features

Proxy & Interception

• Zero-trust MCP proxy — every tool call intercepted regardless of agent cooperation

• Stdio transport support (MCPStdioProxy) for pipe-based MCP clients

• Dry-run mode (--dry-run) — scores and logs without blocking any operations

• Per-operation session tracking, agent identification, and tag propagation

Risk Scoring

• L1 static rules — 8 built-in rules covering destructive file ops, sensitive path writes, database drops, command execution, git force-push

• L2 user history — per-agent Bayesian model (requires ≥10 outcomes)

• L3 community enrichment — configurable HTTP endpoint (opt-in)

Checkpoints & Rollback

• Pre-operation file snapshots into a shadow git repository

• One-command rollback to any checkpoint

• Checkpoint diff view before restoring

• Rollback preview (dry-run before committing restore)

Policy System (see docs/policy-guide.md)

• Custom policy rules loaded from ~/.agentsgate/policy.json

• Per-rule match on tool, method, agentId, pathPattern, params, and tags — exact strings, or /regex/flags

• Rule actions: allow, block, require_approval, or score override

• Agent allowlist / denylist

• Per-agent tool allowlist / denylist

• L1 rule muting and score overrides

• Hot reload with --policy=path; a file that does not parse is ignored and the running policy stays in force

• Presets — agentsgate policy preset apply strict|permissive|readonly

• Live policy stats via the dashboard

Approval Queue

• Operations are held at the stdio proxy until approved or denied — the tool is not called before someone answers, and no answer is a denial

• On the HTTP proxy, approval leaves a one-time grant the agent's retry spends; approvals.holdHttpRequests makes it wait instead

• Webhook notifications (with retry) on enqueue

• Slack Incoming Webhook integration

• Escalation webhooks for stale approvals

• Approvals persist across restarts (SQLite-backed)

• Auto-expiry with configurable TTL (default 24h)

• Real-time SSE push when approvals expire

Dashboard API (see docs/api-reference.md)

• Full REST API: operations, agents, tools, sessions, risk, checkpoints, rollback, approvals, policy, telemetry, circuit breakers, rate limits, quota, audit

• Server-Sent Events (GET /events) for live operation feed

• Prometheus metrics (GET /metrics)

• RBAC via X-API-Key header

• Audit log HMAC-SHA256 verification (GET /audit/verify)

• CSV export for operations

Telemetry & Analytics

• Anonymized aggregate stats — zero PII stored

• Anomaly detection with z-score alerting (configurable threshold)

• Periodic export to a configurable HTTP endpoint

• Per-agent, per-tool, per-session telemetry breakdowns

Plugin Adapters

• BaseRollbackAdapter base class for extending rollback to SaaS tools

• Community adapter registry — load adapters from a directory

Operations Management

• Per-agent and per-tool operation history

• Full-text and filter-based search across operations

• Rate limiting per agent (ops/minute)

• Circuit breaker per agent

• Daily quota management per agent

• Log retention and pruning

Developer / Ops Tools

• agentsgate doctor — environment health check

• agentsgate benchmark — throughput benchmark

• agentsgate inject / eject — auto-configure Claude Desktop

• agentsgate completion — shell autocomplete

Installation

npm install -g agentsgate

Or run directly without installing:

npx agentsgate start

For local development from a fresh clone:

git clone https://github.com/agentsgate/agentsgate.git
cd agentsgate
npm run bootstrap

Quick Start

# Start the proxy (default port 4000, dashboard on port 4001)
agentsgate start

# Start on a custom port
agentsgate start 8080

# Check that the proxy is running
agentsgate status

# Show effective config
agentsgate config

# Show dashboard health
agentsgate health

Configure Claude Desktop

# Auto-inject AgentsGate into Claude Desktop's MCP config
agentsgate inject

# Verify injection
agentsgate status

# Remove injection
agentsgate eject

Restart Claude Desktop after injection. All Claude tool calls now flow through AgentsGate.

CLI Reference

See docs/cli.md for every command and flag, grouped by category. The most common ones:

Dashboard API

While the proxy is running, a REST server on port+1 (default: 4001) provides full visibility and control. See docs/api-reference.md for the complete endpoint reference.

Key features:

• All endpoints (except GET /health) require X-API-Key header when dashboard.apiKey is set

• Real-time events via GET /events (Server-Sent Events)

• Prometheus metrics via GET /metrics

• CSV export via GET /operations/export

• Rollback via POST /rollback/:checkpointId

• Approval management via POST /approvals/:id/approve and POST /approvals/:id/deny

Risk Scoring

Operations are scored 0.0 (safe) → 1.0 (extremely risky) using three layers:

L1 Rules

Thirty rules ship built in. A representative sample follows — agentsgate policy list prints them all, and docs/policy-guide.md covers muting and re-scoring them.

Two things about L1_DB_EXFIL that are easy to trip over:

• Counting is exempt. SELECT count(*) FROM users reveals a number and no column values, so it scores 0.05. Only count() is exempt — max(password) is the largest password verbatim, group_concat(email) returns every row in one string, and sum(balance) WHERE id = 42 is one person's balance.

• Singular and plural both count. user, users, public."User", app_user and user_accounts all match; a column named user_id does not.

Protection levels

Scores alone cannot express what most people want. DROP TABLE scores 1.00 and SELECT * FROM users scores 0.60 — they differ in kind, not degree, so raising the bar until the SELECT passes also clears DELETE FROM orders (0.90). So each rule carries a category, and a level says what to do with each.

agentsgate level              # what is stopped right now, and why
agentsgate level minimal      # switch

The dashboard has the same switch in its header, and changing it there takes effect on the running proxy immediately — no restart — and is written back to config.json so it survives one.

What that means in practice:

                        minimal   balanced   strict
git status              allow     allow      approval
write a file            allow     allow      allow
delete a file           allow     allow      approval
delete a directory      allow     approval   BLOCK
rm -rf node_modules     allow     approval   BLOCK
write to .env           allow     BLOCK      BLOCK
UPDATE ... WHERE id=1   allow     allow      allow
SELECT * FROM users     allow     allow      approval
DROP TABLE              BLOCK     BLOCK      BLOCK
DELETE with no WHERE    BLOCK     BLOCK      BLOCK

balanced is the default because the common case is one person keeping an agent from wrecking their own project: stop the irreversible things and the credentials, and stay out of the way otherwise. Move to strict when the data is not only yours. Policy rules are applied after the level and override it.

Intervention thresholds

Levels decide on the category of an operation. Where no built-in rule fires, the score falls through to these thresholds.

Override thresholds in policy.json or config.json.

How the hold works. Under agentsgate proxy — the mode agentsgate inject configures for Claude Desktop — the tool call is held: the MCP server is not called until someone answers. The operation appears in agentsgate approvals and on the dashboard; agentsgate approve <id> releases it, agentsgate deny <id> refuses it. Nobody answering within approvals.waitTimeoutMs (default 60s) is a denial, as is a dashboard that is not running — the proxy sits synchronously in the request path, so anything it cannot resolve, it refuses.

The HTTP proxy cannot hold the caller by default — it answers "needs approval" straight away, and the operation does not run. Approving leaves a one-time grant: ask the agent to try the same thing again and that retry goes through, once. The grant is for that exact request (same agent, tool, method and arguments) and lapses after approvals.grantTtlMs (default 5 minutes).

Set approvals.holdHttpRequests: true to make the HTTP proxy wait like the stdio one instead, so the original call carries the result. It is off by default because it keeps an HTTP request open for the length of the wait, which reverse proxies and load balancers may cut.

Policy System

Built-in rules score every operation; a policy lets you overrule them — block a tool outright, trust a particular agent, or raise the bar for anything touching /secrets/. Policies live in ~/.agentsgate/policy.json and need no code.

# Never let an agent delete a file
agentsgate policy add --id=NO_DELETES --tool=filesystem \
  --method='/delete|unlink|rm/i' --action=block

# Check it, without involving a real agent
agentsgate policy test --tool=filesystem --method=delete_file

See docs/policy-guide.md for the full guide: matching, rule priority, thresholds, per-agent tool restrictions, tuning the built-in rules, presets, and hot reload.

Plugin Adapters

Extend rollback to external services by implementing RollbackAdapter. See docs/plugin-authoring.md for the full authoring guide.

Quick example:

import { BaseRollbackAdapter } from 'agentsgate';
import type { MCPOperation, RollbackCapability, StateSnapshot, RollbackResult, RollbackPreview } from 'agentsgate';

export default class GitHubIssueAdapter extends BaseRollbackAdapter {
  readonly adapterId = 'github-issues';
  readonly version = '1.0.0';
  readonly supportedTools = ['github', 'github-mcp'];

  async canRollback(operation: MCPOperation): Promise<RollbackCapability> {
    const isDestructive = ['close_issue', 'delete_comment'].includes(operation.method);
    return { canRollback: isDestructive, confidence: 0.9 };
  }

  async captureState(context: MCPOperation): Promise<StateSnapshot> {
    // Snapshot current state before the operation
    return { adapterId: this.adapterId, operationId: context.id, data: {}, capturedAt: new Date() };
  }

  async rollback(snapshot: StateSnapshot): Promise<RollbackResult> {
    // Restore via external API
    return { success: true, restoredFiles: ['github:issue'], failedFiles: [] };
  }

  async previewRollback(snapshot: StateSnapshot): Promise<RollbackPreview> {
    return { willRestore: ['github:issue#1'], cannotRestore: [], warnings: [] };
  }
}

Load adapters at startup:

import { CommunityAdapterRegistry } from 'agentsgate';

const registry = new CommunityAdapterRegistry();
await registry.load('./plugins');   // scans ./plugins/*.js

Configuration

Config file: ~/.agentsgate/config.json. agentsgate config prints the effective configuration; --config=path points any command at another file.

{
  "proxy": { "port": 4000, "host": "127.0.0.1", "checkpointThreshold": 0.3 },
  "intervention": { "allowBelow": 0.3, "blockAtOrAbove": 0.7 },
  "dashboard": { "apiKey": "your-secret-api-key" },
  "audit": { "signingSecret": "your-hmac-secret" }
}

See docs/configuration.md for every field, its default, and the full example — webhooks, Slack, telemetry, OTLP, rate limiting, log retention, dashboard roles and host allowlisting.

Architecture

Project structure

src/
  cli.ts                  ← agentsgate CLI entry point
  index.ts                ← library exports
  config.ts               ← configuration loader
  policy.ts               ← policy engine
  types/
    interfaces.ts         ← all shared types (Architect-owned)
    errors.ts             ← typed error classes
  modules/
    m1-proxy/             ← MCP proxy + createPipeline factory
    m2-store/             ← SQLite state store
    m3-logger/            ← operation logger
    m4-checkpoint/        ← checkpoint engine
    m5-shadow/            ← file shadow system
    m6-risk/              ← risk scoring engine (L1)
    m7-intervention/      ← intervention controller
    m8-rollback/          ← rollback engine
    m9-plugin-sdk/        ← plugin adapter SDK
    m10-dashboard/        ← dashboard REST API + SSE
    m11-intelligence/     ← risk intelligence (L2/L3)
    m12-registry/         ← community adapter registry
    m13-telemetry/        ← anonymized telemetry
  utils/
    rate-limiter.ts       ← per-agent rate limiting
    circuit-breaker.ts    ← per-agent circuit breaker
    agent-quota.ts        ← per-agent daily quota
    graceful-shutdown.ts  ← signal handling + drain
    slack-notifier.ts     ← Slack webhook notifications
    claude-desktop-injector.ts ← Claude Desktop config management
    mcp-server-registry.ts ← MCP server discovery
tests/
  modules/                ← unit tests (one file per module)
  e2e/                    ← end-to-end pipeline tests

Development

git clone https://github.com/agentsgate/agentsgate.git
cd agentsgate
npm install
npm run build      # compile TypeScript
npm test           # run full test suite
npm run typecheck  # type-check without building

Recommended first run:

npm run bootstrap
npm run smoke:start
node dist/cli.js start

Contributing

Contributions are welcome. Please open an issue to discuss proposed changes before submitting a pull request.

License

MIT — see LICENSE