Otskit MCP

What otskit-mcp MCP server does

The otskit-mcp MCP server provides MCP tools for creating and checking OpenTimestamps records associated with Bitcoin. Agents can submit a SHA-256 hash to four public OTS calendars, compute a file hash locally, or hash and stamp a file in one operation. The server also stores stamp records and proof files in a local SQLite database under ~/.ots-mcp/.

The available operations cover the main timestamp lifecycle:

• Create a timestamp for a hash or local file.
• Check whether a pending timestamp has received a Bitcoin confirmation.
• Verify that a hash existed before a specified Bitcoin block.
• Verify an external .ots proof for a whitelisted local file without modifying the local stamp store.
• Inspect a stored proof without making network requests.
• List pending records with status, retry count, and filters.

The project is an independent implementation of the OpenTimestamps protocol and is not affiliated with the OpenTimestamps project.

How it works

A file is reduced to a SHA-256 digest before it is sent for stamping. The timestamp request is submitted against four configured public OTS calendars. A newly created proof remains pending until the Bitcoin network confirms it; confirmation commonly takes around an hour but may take several hours when the network is congested. A pending result does not indicate failure.

upgrade_timestamp checks whether a pending record can be completed. The watch tool can monitor pending records and attempt due upgrades, while the command-line scheduler can automate upgrade passes. Verification uses the resulting proof to establish that the hash existed before a Bitcoin block. Local hashing and proof inspection do not require network calls. No API keys are required.

Setup and configuration

Install the package globally with:

npm install -g @otskit/mcp

The otskit-mcp MCP server requires Node.js 20 or later. Start it directly with ots-mcp serve, which uses stdio transport. For Claude Desktop, run ots-mcp setup claude; the setup command writes the MCP entry to the agent configuration, creates a .bak backup when an existing configuration is present, and skips duplicate configuration. Restart the agent after setup. Setup commands are also provided for Claude Code and Codex CLI.

Persistent files are stored in ~/.ots-mcp/: ots-mcp.db contains stamps and proof files, config.json holds optional overrides, and ots-mcp.log contains logs. Configuration can change whether stamping is enabled, the scheduler interval, retry limit, calendar timeout, and the list of calendar URLs.

Tools and capabilities

The otskit-mcp MCP server exposes create_timestamp, upgrade_timestamp, verify_timestamp, verify_external_proof, inspect_timestamp, list_pending, watch, hash_file, and stamp_file. Its CLI additionally supports one-off stamping, upgrading, verification, pending-record checks, database backups, and scheduler installation, removal, or status checks.

The command-line watch interval defaults to 30 minutes and has a 15-minute minimum. Automatic confirmation still depends on Bitcoin confirmation and the availability of the configured OTS calendars.

Limitations and notes

Operations that contact calendars or check Bitcoin status require network access, while hashing and stored-proof inspection do not. Confirmation timing is variable, especially during network congestion. The server uses public OTS calendar endpoints by default and stores its records locally in SQLite. The provided material does not identify an explicit software license name.