Utuh

Utuh bonds the claim that a set of events is complete, pays half the bond to anyone who proves one event was left out, and lends CTC undercollateralized against the claims that survive.

utuh — Indonesian: whole, intact, with nothing missing. A completeness layer for the Attestcoin Protocol, built for BUIDL CTC 2026 Fall and deployed on Creditcoin CC3 Testnet.

• Live: utuh.vercel.app (landing, read from Creditcoin as it draws) and the console at utuh.vercel.app/app/ (sweep, refute, borrow; no server, no clone).
• Two refuted claims, one click each: claim 5, sealed one event short and broken from a browser · claim 20, a false "never liquidated" over 216,000 Ethereum mainnet blocks, refuted by one liquidation proof

The landing page, claim 5 as a working paper	The console, claim 20 opened verdict first
Dark scheme	A sweep of claim 5 from the browser, with its provenance

• Verify every number yourself: npm run judge — no key. It re-measures every number this repository and the submission quote against the live chain and exits non-zero on any that no longer holds. On 2026-09-14, after the production deploy, it printed 25 of 25, two of them checks that read the example gate below.
• Hold the watcher role from an agent: npx -y utuh-mcp — 0.4.0 on npm and in the official MCP Registry. For clients that cannot run a command, the same server answers at https://utuh.vercel.app/api/mcp (below).
• Measured: 211 Foundry tests with 16 invariants, 100% line and branch coverage and 99.1% of 737 mutants killed · Slither 0 findings · halmos 5 of 5 · every contract verified on Blockscout and matched on Sourcify · 248 TransactionVerified events on CC3's own indexer.
• Demo video (3 min): https://youtu.be/HwSnv3E4tzo · Whitepaper: PDF, from web/whitepaper.html · Deck: web/deck.pdf

What is on-chain, all verified on Blockscout and Sourcify (every address and read):

A contract that is not Utuh reads it: NeverLiquidatedGate at 0xcA62…5D09 granted an allowance on claim 72 and refused refuted claim 20. This project wrote and deployed it as the worked example, so it is not an outside user.

Contents

The short version · The problem · What this uses of Creditcoin's · Next to Creditcoin's own example · What Utuh does · Built on Ethereum mainnet · UtuhCredit · Deployed on CC3 Testnet · Two demonstrations · The watcher as an MCP server · The console · Layout · Running it · On testing · What the tools say · Before you build on this · Attestcoin surface used · Known limits · License

Elsewhere: docs/INTEGRATING.md (use the registry from your own contract) · docs/COMPLETENESS.md (does what you built have this gap?) · docs/ROADMAP.md (what is gated on whom) · docs/AUDIT.md · docs/MAINNET.md · SECURITY.md · 한국어 요약: docs/README.ko.md

The short version

Any registry on this protocol can tell you what it holds. Ask one whether a borrower has ever been liquidated and it can only answer with what someone chose to submit — and the borrower will not be submitting that. Utuh bonds the claim that a set is all of them, and pays half the bond to anyone who proves one event was left out.

The landing page reads both registries from Creditcoin as it draws — the two refuted claims with their block-range strips, the tally (proven, sealed, broken, burned), the deployed addresses — and each deep link above opens the console on the claim with its verdict first. The console reads the chain from your own browser, lets anyone sweep Ethereum and break an incomplete claim, and lets a borrower be underwritten end to end without cloning anything. npm run web serves both locally. Every verification behind the two refuted claims is on Creditcoin's own oracle dashboard, which nobody here can write to.

Two things a reader with a clone and no key can check first. npm run judge re-measures every number this repository and the submission quote — the contracts and their verification, the tally, both linked claims, the explorer counters, npm, the MCP Registry, the published build, the sixteen protocol entry points, the test and commit counts — and exits non-zero on any that no longer holds. And a bond here stands behind a specific line, not behind nothing: UtuhCredit.openLine reaches a claim only through UtuhRegistry.isUsable(claimId, exposure), the finalized claim is spent by the line it opens, underwrittenThrough consumes the history range, and the limit is capped at ten times the enforceable loss. Exposure is gated by the bond and consumed by the draw.

The problem

The Attestcoin Protocol proves that a source-chain transaction happened. A Merkle proof places the transaction in a block; a continuity proof anchors that block to an attestation stored on Creditcoin. The Block Prover precompile at 0x0FD2 checks both natively, synchronously, inside a single Creditcoin block.

What it cannot prove is that a set of events is complete.

Whoever submits proofs chooses which proofs to submit. Every one of them verifies. Nothing in the protocol notices the ones that were left out.

For credit, that gap is fatal. The sentence every on-chain credit system needs is:

This borrower has never been liquidated.

That is a statement about events which do not exist, and an inclusion proof can only ever speak about events which do. A borrower assembles their own history, submits the flattering half, and each proof checks out.

This is not hypothetical. Season 1 of this hackathon drew 76 submissions, and more than twenty of them were some form of on-chain credit score or reputation-based lending; one of those, CreditX, took a prize. Every one of them inherits this hole, the winner included — placing well is not the same as closing it, and an inclusion proof gives none of them a way to.

What this uses of Creditcoin's, and what it deliberately does not

npm run doctor (no key needed; given one it also reports the balance) ends by making a live request to every Creditcoin-owned surface this depends on, so the list below is checkable rather than asserted. A run on 2026-09-10: