Témoin public — Claude Code MCP server: what it does, how to install
Proves a document or web page existed on a specific date using a public SHA-256 registry anchored in Bitcoin. Keeps your file content private.
claude mcp add --transport http temoinpublic https://temoinpublic.fr/mcpWhat Témoin public does
The server connects an assistant to a public ledger of SHA-256 digests. In every round, hashes of archived files form a Merkle tree linked to the previous round. The resulting root anchors into Bitcoin via OpenTimestamps and carries an eIDAS timestamp.
The ledger never stores raw documents. It contains only hashes, tree roots, and anchor proofs. You can inspect any record using scripts/verifier.mjs, which runs in Node.js or browsers without extra packages.
Offline verification of proofs on your local machine requires ots and openssl command-line tools.
What it helps with
- prove document existence on a specific date
- verify SHA-256 hash chains and Merkle tree roots
- confirm Bitcoin anchoring through OpenTimestamps
- validate eIDAS timestamp tokens for archived files
Example prompts for the agent
- Verify this SHA-256 checksum against the Témoin public registry
- Check whether the document hash has an OpenTimestamps Bitcoin proof
- Inspect the Merkle root chain for this archived record
How to install Témoin public
Platform CLI: remote server
claude mcp add --transport http temoinpublic https://temoinpublic.fr/mcpPlatform CLI: remote server
codex mcp add temoin-public --url https://temoinpublic.fr/mcpConfig file
{
"mcpServers": {
"temoin-public": {
"url": "https://temoinpublic.fr/mcp"
}
}
}Config file
{
"servers": {
"temoin-public": {
"type": "http",
"url": "https://temoinpublic.fr/mcp"
}
}
}Platform CLI: remote server
gemini mcp add -t http temoin-public https://temoinpublic.fr/mcpStep by step, with commands for each platform: How to add an MCP server to Claude Code, Codex, Cursor, VS Code, Gemini CLI and more
Questions about Témoin public
How to install Témoin public in Claude Code?
Run claude mcp add --transport http temoinpublic https://temoinpublic.fr/mcp in your terminal.
What does Témoin public do?
It queries an open SHA-256 ledger to verify that a file or webpage existed at a proven point in time.
Does Témoin public upload or store file contents?
No, the registry holds only SHA-256 hashes, Merkle roots, and cryptographic proofs, keeping raw file contents private.
