External validation · no money · no production authority

Bind approved intent to verified effect.

Run MUJ428 from a system MUJ428 does not control. The challenge exercises authorization → authenticated Trust Receipt consumption → COMMITTED Verified Effect → replay denial in the public TESTNET_CONFORMANCE sandbox.

$0moves_money=falseproduction_authority=falseMCP Registry v1.6.4

Open runnable example Machine contract
1 · Authorize

Bind the proposed action

The sandbox issues an authenticated receipt bound to the requested action and current premises.

2 · Execute

Consume at the boundary

The executor validates and consumes the receipt before committing the sandbox effect.

3 · Prove

Verify the effect

A Verified Effect records COMMITTED; replaying the same authorization must be denied.

Fastest run

Download the public example and run it from your own environment. No wallet, payment signature, API key, or paid credential is required.

curl -fsS https://agents.muj428.com/examples/external-verified-effect.mjs -o external-verified-effect.mjs
node external-verified-effect.mjs

A valid run should show a sandbox authorization, one successful committed Verified Effect, and a denied replay. A MUJ428-controlled CI run does not count as external adoption; an independently attributable outside run does.

What to send back

For independent validation, share only non-secret evidence: your organization/project name, run timestamp, environment, resulting effect state, and whether replay was denied. Do not send private keys, payment credentials, or proprietary payloads.

Technical contact: agent@muj428.com · Commercial contact: sales@muj428.com

After the $0 proof

Use MUJ428 in a real workflow through REST, MCP, A2A, x402, or framework middleware. Paid assurance options include the $39 Evidence Signal and transaction assurance for higher-value consequential actions.

View pricing Developer contract MCP Server Card

Verification boundaries

Glossary & terminology