Volta MCP Server

What iamredmh/volta-mcp-server MCP server does

The iamredmh/volta-mcp-server MCP server connects an MCP-compatible agent to Volta Notes, a service for single-use encrypted notes. It supports two operations: creating a note containing secret text and reading a note from its complete Volta URL.

A created note is intended for short-lived credential exchange. For example, a user can paste an API key into Volta Notes and give the resulting one-time URL to an agent. The agent can then retrieve the content with the read tool. The reverse flow is also supported: an agent can create a note and send the link to a user.

The note content limit is 2 KB. Notes are permanently removed after a successful read, and unread notes expire after seven days. The README states that the service does not require accounts, login, or tracking.

How it works

The iamredmh/volta-mcp-server MCP server uses AES-256-GCM encryption. For note creation, encryption happens locally before ciphertext is sent to the Internet Computer canister that stores the note. The resulting URL contains a note identifier and the decryption key in its fragment portion.

URL fragments are not transmitted in ordinary HTTP requests. As a result, the key is kept out of the server-side request, while the canister receives only ciphertext. When a recipient reads a note, the stored ciphertext is fetched, the note is deleted by the canister, and the content is decrypted using the key from the URL fragment.

A second attempt to read the same note fails because the note has already been destroyed. This workflow is suited to runtime secrets such as API keys, passwords, and other credentials that should not remain in an agent conversation.

Setup and configuration

The package requires Node.js 18 or later and uses the built-in Web Crypto API. It can be run through an MCP client's standard command-and-arguments configuration:

{
  "command": "npx",
  "args": ["-y", "@voltanotes/mcp"]
}

For Claude Desktop, place that command in the mcpServers section of claude_desktop_config.json. The same configuration format is documented for Cursor, Windsurf, Cline, and other compatible clients. Claude Code can register the server with its MCP command, while Hermes Agent can use the equivalent npx command and package name in its MCP YAML configuration.

No environment variables or API credentials are listed as requirements. After registration, restart the client if required and verify the connection using the client's MCP status tools. Successful startup logs Volta MCP server started to standard error.

Tools and capabilities

The iamredmh/volta-mcp-server MCP server exposes these tools:

• create_volta_note: Accepts a content string of up to 2 KB, encrypts it, and returns a one-time voltanotes.com URL.
• read_volta_note: Accepts the full Volta URL, including its # fragment, and returns the decrypted note content while permanently destroying the note.

The URL must include the fragment for decryption. A URL without the fragment cannot provide the key required to recover the plaintext.

Limitations and notes

This server is designed for secrets that can be read once, not for durable storage or repeated access. The one-time behavior means recipients should preserve the complete URL until it is used, but should not expect it to work again afterward.

The security model depends on protecting the URL fragment. Anyone who obtains the complete one-time URL may be able to read the note before it is consumed. Notes are limited to 2 KB and unread notes expire after seven days. The README documents support for Node.js 18+; it does not describe configuration options for changing storage, expiration, or encryption behavior.