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Everything you need to connect, configure, and operate UNDISK MCP.

# What is UNDISK?

UNDISK MCP is a remote file workspace for AI agents. Every file mutation an agent makes over MCP creates an immutable version — so any single write can be surgically undone in under 50ms without affecting other files.

No VM rollbacks. No "restore everything." Just precise, per-file undo with a tamper-evident audit trail.

# Quick Start

1. Sign up — mcp.undisk.app/signup

2. Get your API key — shown once after signup at /keys

3. Connect your MCP client:

https://mcp.undisk.app

claude mcp add --transport http undisk https://mcp.undisk.app

{
  "mcpServers": {
    "undisk": {
      "command": "npx",
      "args": ["-y", "mcp-remote", "https://mcp.undisk.app"],
      "env": {
        "UNDISK_API_KEY": "YOUR_KEY"
      }
    }
  }
}

URL:   https://mcp.undisk.app
Auth:  Bearer YOUR_KEY

Connect to my Undisk MCP workspace at https://mcp.undisk.app
using Streamable HTTP transport. Authenticate with my API key.

# MCP Tools

10 tools exposed via the Model Context Protocol. Every write is versioned.

# Authentication

All MCP connections require a Bearer token. Get your API key at /keys after signing up.

Authorization: Bearer sk_live_...

API keys are shown once at creation and stored as SHA-256 hashes. If you lose your key, regenerate at /keys — this revokes all previous keys.

# How Versioning Works

Every file mutation (write, delete, move) creates an immutable version. Versions are content-addressed via SHA-256 — identical content deduplicates automatically.

# The Undo Moment

This is the core product interaction:

# Agent writes a bad file
→ write_file("/config.yml", bad_content)
  version: ver_a1b2c3

# See what happened
→ list_versions("/config.yml")
  ver_a1b2c3  2026-04-06 11:20  agent_claude  4.1 KB
  ver_x9y8z7  2026-04-06 11:15  agent_claude  3.8 KB  ← good

# Restore the good version
→ restore_version("ver_x9y8z7")
  restored in 8ms. new version: ver_d4e5f6

Restore is a non-destructive operation — it creates a new version with the old content. No data is ever lost within the retention window.

# Policy Engine

Control what agents can do with path-based access control lists, file size limits, rate caps, and anomaly alerts. Policies are configured via the API.

{
  "path_acls": [
    { "path": "/production/**", "agents": "*", "permissions": ["read"] },
    { "path": "/drafts/**", "agents": "*", "permissions": ["read", "write", "delete"] },
    { "path": "/secrets/**", "agents": "*", "permissions": [] }
  ],
  "limits": {
    "max_file_size_mb": 10,
    "max_ops_per_minute": 1000
  },
  "alerts": [
    { "condition": "delete_count_per_hour > 50", "action": "block_and_notify" }
  ]
}

Permission denials return explanatory errors — the agent is told which policy blocked the action and why, not just "access denied."

# Audit Trail

Every operation is logged with a tamper-evident audit entry. Entries include agent identity, human principal, operation type, file path, content hash, and policy evaluation result.

{
  "timestamp": "2026-04-06T10:00:00.000Z",
  "workspace_id": "ws_abc123",
  "agent_id": "agent_claude_prod",
  "human_principal": "user@company.com",
  "operation": "write_file",
  "file_path": "/regulatory/q2-report.md",
  "version_id": "ver_a1b2c3",
  "content_hash": "sha256:e3b0c44298fc1c...",
  "content_size_bytes": 4096,
  "policy_evaluation": {
    "rules_checked": ["max_file_size", "path_acl"],
    "result": "ALLOW"
  }
}

Export audit logs as NDJSON with integrity verification hashes. See /docs/compliance for retention policies.

# Transports

UNDISK supports multiple MCP transports:

# Architecture

# Pricing

Free tier version retention is 7 days. This does not meet the EU AI Act Article 26(6) minimum of 6 months — upgrade to Pro or above for compliance-grade retention.

# Error Responses

All MCP errors include structured context so agents (and humans) understand what went wrong.

# Limits

→ Compliance Documentation

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