Add Signet - cryptographic action signing for MCP tool calls

[willamhou]

Add Signet to the Community Servers section.

What is Signet?

Signet signs every MCP tool call with Ed25519 and maintains a hash-chained audit log. It's a client-side SigningTransport that wraps any MCP transport — servers don't need to change.

import { generateKeypair } from "@signet-auth/core";
import { SigningTransport } from "@signet-auth/mcp";

const { secretKey } = generateKeypair();
const transport = new SigningTransport(innerTransport, secretKey, "my-agent");
// Every tools/call is now signed, receipt injected into params._meta._signet

Details

• Rust core (ed25519-dalek) compiled to WASM for Node.js
• npm: @signet-auth/mcp, @signet-auth/core
• crates.io: signet-core
• CLI for identity/sign/verify/audit
• 83 tests, Apache-2.0 / MIT

[olaservo]

Thanks for contributing to the MCP servers repo!

We've retired the third-party server list from the README in favor of the MCP Registry — see #3950 for context. The Official Integrations and Community Servers sections no longer exist in the README, so this PR no longer has a target.

Going forward, please publish your server to the MCP Registry using the quickstart guide:
https://github.com/modelcontextprotocol/registry/blob/main/docs/modelcontextprotocol-io/quickstart.mdx

That's where server discovery now happens. Thanks for building on MCP!

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Note: I'm working through the backlog with help from Claude Code to give everyone a prompt response.