Skip to main content
Glama
Agentic-Chat-Rooms-Protocol

ACR Meta-MCP Forward Proxy

Official

ACR Meta-MCP Forward Proxy & Governance Control Plane

License: Apache 2.0 NPM Organization Tests: 30 Passing TypeScript: Strict

The ACR Meta-MCP Forward Proxy is an enterprise-grade Model Context Protocol (MCP) reverse and forward proxy, sandbox runtime, and dual-consent governance engine. It implements the dual-layer MCP architecture for the Agentic Chat Rooms (ACR) ecosystem: a native/master MCP layer for internal platform orchestration and a governed Meta-MCP fabric for proxying, sandboxing, credential vaulting, and policy-controlling third-party MCP servers (stdio, SSE, Streamable HTTP).


Architecture Overview

                          ┌────────────────────────────────────────────────────────┐
                          │               ACR Native / Master Layer                │
                          │        (Agent Trust Ledger, JetStream Bus, DIDs)       │
                          └───────────────────────────┬────────────────────────────┘
                                                      │ Dual-Consent Gate
┌─────────────────────────────────────────────────────▼─────────────────────────────────────────────────────┐
│                                       ACR Meta-MCP Forward Proxy (Port 20445)                             │
│                                                                                                           │
│  ┌───────────────────────┐   ┌────────────────────────┐   ┌────────────────────────────────────────────┐  │
│  │ Config Ingestion      │   │ Policy Engine          │   │ Auth Vault (SQLite3MultipleCiphers)        │  │
│  │ • Schema Validation   │   │ • Role & Room Scoping  │   │ • AES-256-GCM / ChaCha20-Poly1305 / CBC   │  │
│  │ • Secret Redaction    │   │ • Quarantine Control   │   │ • PBKDF2-HMAC-SHA512 (256,000 iters)       │  │
│  │ • SHA-256 Fingerprint │   │ • Escalation Hooks     │   │ • Multi-Domain Isolation (Personal/Org)    │  │
│  └───────────┬───────────┘   └───────────┬────────────┘   └─────────────────────┬──────────────────────┘  │
│              │                           │                                      │                         │
│              └───────────────────────────┼──────────────────────────────────────┘                         │
│                                          │                                                                │
│                        ┌─────────────────▼──────────────────┐                                             │
│                        │      3-Tier Catalog Projector      │                                             │
│                        │  Raw -> Policy -> Projected View   │                                             │
│                        └─────────────────┬──────────────────┘                                             │
│                                          │                                                                │
│  ┌───────────────────────────────────────▼─────────────────────────────────────────────────────────────┐  │
│  │                                Transport Bridge & Sandbox Execution                                 │  │
│  │  • Stdio Child Process (ToolHive Sandbox: no-network | egress-allowlist | workspace-scoped)          │  │
│  │  • Streamable HTTP JSON-RPC 2.0 Endpoint (POST /mcp)                                                │  │
│  │  • Server-Sent Events (SSE) Multiplexed Tunneling                                                   │  │
│  └─────────────────────────────────────────────────────────────────────────────────────────────────────┘  │
└───────────────────────────────────────────────────────────────────────────────────────────────────────────┘

Related MCP server: lazy-mcp-router

Key Modules & Capabilities

1. Config Ingestion (packages/config-parser)

  • Ingests standard mcp_config.json containing stdio (command/args/env) and remote (url/headers) server definitions.

  • Automatically redacts inline credentials and tokens into deterministic reference placeholders (sec_ref_<server>_<key>).

  • Generates canonical SHA-256 fingerprints for immutable InstallManifest versioning.

2. Multi-Cipher Auth Vault (packages/auth-vault)

  • Fuses the cryptographic designs of utelle/SQLite3MultipleCiphers and sqlcipher/sqlcipher.

  • Encrypted at rest (vault.db) with 64-byte authenticated magic header ACR_MCDB_V1.

  • Supported Ciphers:

    • aes-256-gcm (NIST SP 800-38D AEAD)

    • chacha20-poly1305 (RFC 8439 AEAD)

    • sqlcipher-v4 (AES-256-CBC + HMAC-SHA512 per record)

  • Key Derivation: PBKDF2-HMAC-SHA512 (256,000 iterations default) with per-database random salts.

  • Domain Boundaries: personal, org, enterprise, ephemeral.

  • Master Passphrase Rotation: Atomic re-encryption of all database records.

3. ToolHive-Inspired Sandbox Containment (packages/sandbox-runtime)

  • Isolates untrusted stdio processes using 4 containment profiles:

    • no-network: Prohibits external network calls; scrubs proxy settings.

    • egress-allowlist: Allows outbound HTTP/HTTPS exclusively to verified endpoints (e.g. api.github.com, gitee.com).

    • filesystem-readonly: Blocks write operations outside ephemeral runtime /tmp.

    • workspace-scoped: Restricts disk access strictly to designated project directories.

  • Host environment variable sanitization and execution timeout bounds.

  • Enforces access control at both the Master Layer and Meta-MCP Proxy Layer.

  • Scopes tool accessibility by caller role (admin, agent, human_operator, guest) and active room deliberation context.

  • Instant server quarantine mechanism (toggleQuarantine).

  • Human operator confirmation hooks (REQUIRE_HUMAN_CONFIRMATION).

5. 3-Tier Catalog Projector (packages/catalog-projector)

  • Raw Catalog: All tools discovered from downstream servers with prefix namespacing (${serverId}__${toolName}).

  • Policy Catalog: Tools that pass server health, non-quarantine, and policy permission checks.

  • Projected Catalog: Persona-filtered tool view tailored to the requesting agent DID and permissions.

6. Control Plane API & Streamable Gateway (apps/control-plane-api)

  • Native HTTP daemon running on port 20445.

  • Private Network Access (PNA) and CORS compliant (Access-Control-Allow-Private-Network: true).

  • Streamable HTTP JSON-RPC 2.0 gateway at POST /mcp.

  • Replay audit logging with sub-millisecond precision.


Environment Variables

Variable

Default

Description

ACR_META_MCP_PORT

20445

HTTP listen port for Control Plane and MCP Gateway

ACR_META_MCP_HOST

0.0.0.0

Listen host interface

ACR_VAULT_PATH

(in-memory)

File path to encrypted MultipleCiphers database (vault.db)

ACR_VAULT_SECRET

(generated)

Master encryption secret for Auth Vault

CONTEXT7_API_KEY

(optional)

Dynamic API key for Context7 real-time library docs MCP


REST API Reference

Method

Endpoint

Description

GET

/health

Daemon status, version, server count, uptime

GET

/api/v1/meta-mcp/servers

List registered downstream MCP servers

POST

/api/v1/meta-mcp/servers/import

Import and compile standard mcp_config.json

POST

/api/v1/meta-mcp/servers/:id/toggle

Enable or disable a registered server

POST

/api/v1/meta-mcp/servers/:id/quarantine

Toggle quarantine status for a server

GET

/api/v1/meta-mcp/tools

Query tool catalog (?view=raw|policy|projected)

POST

/api/v1/meta-mcp/tools/call

Invoke a governed tool execution

GET

/api/v1/meta-mcp/vault/secrets

List vaulted secret refs with domain & cipher info

POST

/api/v1/meta-mcp/vault/secrets

Store an encrypted secret in the MultipleCiphers DB

DELETE

/api/v1/meta-mcp/vault/secrets/:refId

Purge a secret from the encrypted DB

POST

/api/v1/meta-mcp/vault/rotate

Rotate master passphrase & re-encrypt DB

GET

/api/v1/meta-mcp/audit

Replay cryptographic audit trail logs

POST

/mcp

Streamable HTTP JSON-RPC 2.0 MCP Gateway


CLI Usage

Standalone Node CLI (@acr-js/meta-mcp)

# Check daemon health
acr-meta-mcp health

# List registered servers
acr-meta-mcp list

# Import mcp_config.json
acr-meta-mcp import ./path/to/mcp_config.json

# Query tools catalog
acr-meta-mcp tools projected

# Call governed tool
acr-meta-mcp call context7__query-docs '{"libraryId":"/vercel/next.js","query":"App Router"}'

# Manage encrypted Auth Vault
acr-meta-mcp vault list
acr-meta-mcp vault set context7 CONTEXT7_API_KEY "ctx7sk_..." personal chacha20-poly1305
acr-meta-mcp vault rotate "new-secure-passphrase"
acr-meta-mcp vault delete sec_ref_context7_context7_api_key

# Manage and test dynamic port bindings
acr-meta-mcp ports list
acr-meta-mcp ports set acr-meta-mcp 20495
acr-meta-mcp ports test
acr-meta-mcp ports export

# View audit logs
acr-meta-mcp audit

Native Dart CLI (acr-cli)

acr meta-mcp list
acr meta-mcp import ./mcp_config.json
acr meta-mcp tools --view=projected
acr meta-mcp call context7__resolve-library-id '{"libraryName":"React"}'
acr meta-mcp vault list
acr meta-mcp vault set --server=github --key=GITHUB_TOKEN --value="ghp_..."
acr ports list
acr ports set acr-meta-mcp 20495
acr ports test
acr meta-mcp audit

Integration with MCP Clients

Add the ACR Meta-MCP Forward Proxy to any standard MCP client (claude_desktop_config.json, ~/.cursor/mcp.json, etc.):

{
  "mcpServers": {
    "acr-meta-mcp": {
      "url": "http://localhost:20445/mcp"
    }
  }
}

All downstream tools (Context7, GitHub, Gitee, filesystem sandbox, custom agents) will be dynamically projected, sandboxed, and governed under dual-consent policy rules.


Test Suite Execution

npm install
npm test
✔ Meta-MCP Control Plane API & JSON-RPC Gateway (8 tests passed)
✔ Context7 Real MCP Tool E2E Integration & QA Test (7 tests passed)
✔ Auth Vault (SQLite3MultipleCiphers & SQLCipher Engine) (5 tests passed)
✔ Catalog Projector (3-Tier Catalog Pipeline) (2 tests passed)
✔ Config Parser & Manifest Compiler (2 tests passed)
✔ Policy Engine & Dual Consent (3 tests passed)
✔ Registry Core (State Machine & Server Persistence) (1 test passed)
✔ Sandbox Runtime (Containment Engine) (2 tests passed)

30 tests passed, 0 failed (971ms)

Maintenance

ActivityMaintained
ResponsivenessNo issues

Resources

Unclaimed servers have limited discoverability.

Looking for Admin?

If you are the server author, to access and configure the admin panel.

Related MCP Connectors

Related MCP Servers

  • F
    license
    Not graded
    quality
    A
    maintenance
    A production-ready MCP gateway and control plane that provides credential vault, policy engine, audit logging, and managed runtime for routing tool calls between AI agents and downstream MCP servers.
    58
  • F
    license
    Not graded
    quality
    C
    maintenance
    Safety-first local MCP tool gate with control plane, runtime security, and observability for managing MCP backends.
  • A
    license
    A
    quality
    A
    maintenance
    A zero-dependency MCP gateway: host your own tools, forward and curate tools from other MCP servers, expose them leanly to cut agent token cost, and gate every call through your own policy hooks before it runs.
    2
    4
    25
    35
    MIT
  • A
    license
    Not graded
    quality
    B
    maintenance
    Self-hosted MCP gateway that applies deterministic, compiled policy to tool discovery, invocation, and outbound data flow, with no model in the enforcement path. Every decision emits a hash-chained receipt sealed with Ed25519 and verifiable using public keys only.
    Apache 2.0

Latest Blog Posts

MCP directory API

We provide all the information about MCP servers via our MCP API.

curl -X GET 'https://glama.ai/api/mcp/v1/servers/Agentic-Chat-Rooms-Protocol/acr-meta-mcp'

If you have feedback or need assistance with the MCP directory API, please join our Discord server