Canonicalhash

io.github.Mlartab2Published by GitHub account Mlartab2v1.0.0Updated Oct 26, 2026

Deterministic JSON hashing and EIP-712 attestations for AI agents via x402.

VerifiedStreamable HTTPWeb executableDeveloper ToolsSecurity & Monitoring

Overview

AI-generated overview

Remote MCP server that canonicalizes JSON, returns SHA-256 hashes, and issues EIP-712 signed attestations and receipts for agent actions.

What you can do
  • Canonicalize JSON per RFC 8785 and get a SHA-256 hash with an EIP-712 signed attestation
  • Batch canonicalize up to 1000 JSON payloads in a single call
  • Create tamper-evident EIP-712 receipts for agent decisions
  • Extract structured JSON from messy text such as emails, logs or tickets using regex or Needle 3
  • Verify an EIP-712 attestation against the published public key
When to use it
Useful when an assistant needs reproducible hashes of JSON data, or a verifiable, signed record that a particular decision or payload existed in a given form, for example for audit trails or agent-to-agent trust.
Requirements
A remote streamable HTTP endpoint; no local package, account, API key or header is declared. The registry description mentions x402, which typically implies paid calls, but no pricing details are given.
Before you install
The description references x402, so some tools may require payment; only verification is stated to be free. Receipts and attestations are signed with a service-held key, so trust depends on that operator and its published public key. Payloads sent for canonicalization or extraction leave your machine for a third-party server.

Installation

In SourceWeft

  1. Open Canonicalhash in the dashboard and add it to a workspace.
  2. Enable the server for the chats that should use its tools.

Web executable via Streamable HTTP. Remote servers run from the web runtime once configured in a workspace.

Use with an agent

Paste this prompt into Claude Code, Codex, Cursor or another agent — or into SourceWeft chat. The agent reads this server's install guide, shows you its publisher, endpoint and sign-in, and adds it to your client once you agree. Keys never go into a command.

Read https://sourceweft.com/mcp/io.github.Mlartab2%2Fcanonicalhash/install.md and connect the MCP server it describes to my client. Before changing any config, show me its publisher, endpoint and sign-in method and wait for my OK. Never put an API key in a command or in a file I would commit; ask me where it should come from.

Read the install guide the agent follows

Other MCP clients

Add this to your client's mcpServers config.

{
  "mcpServers": {
    "canonicalhash": {
      "type": "http",
      "url": "https://canonicalhash-production.up.railway.app/mcp"
    }
  }
}

README

This repository has no README.

Tools

5

canonicalize

Canonicalize JSON with RFC 8785 and return a SHA-256 hash plus an EIP-712 signed attestation.

Parameterspayloadrequiredalgorithm

batch_canonicalize

Batch canonicalize up to 1000 JSON payloads in one call.

Parameterspayloadsrequired

create_receipt

Generate a tamper-evident EIP-712 action receipt for an agent decision.

Parametersactionrequiredmetadata

structure_extraction

Extract structured JSON from messy text (emails, logs, tickets) using regex or Needle 3.

Parameterstextrequiredschema

verify_attestation

Verify an EIP-712 attestation against the published public key. Always free.

Parametersattestationrequired

Version history

1
  1. v1.0.0LatestOct 18, 2026

Score

75% of the applicable checks met

How complete this listing is, computed from the registry entry, the endpoint and public sources. Not a rating of the server and not a statement that it is safe or working today: reachability is a dated check, and no installs or reviews go into the score.

  • Reached in the last 30 daysRequired25 pts
  • Auth declaredRequired10 pts
  • Tools listedRequired15 pts
  • DescriptionRequired15 pts
  • Logo10 pts
  • Documentation15 pts

    Declare a GitHub repository with a README, or serve resource_documentation in the OAuth protected-resource metadata.

  • License10 pts

    Declare a license in the repository or the registry entry.