Cosmos Lab

A Cosmos signed header and two chained ICS-23 proofs, captured once and replayed offline.

The header, its validator set and both state proofs were captured from osmo-test-5 at height 68199363 on 2026-08-11T18:56:17Z and are frozen. Nothing on this page contacts a network while it serves you a request — the bytes are compiled into the binary and the verification is arithmetic over them.

This is not a light client. A light client follows a chain: it holds a trusted header, asks for new ones, and updates what it trusts within a trust period. There is none of that here. What there is, is a verifier that can be watched refusing things.

Where the data came from

Network

osmo-test-5

Endpoint

https://rpc.osmotest5.osmosis.zone

CometBFT

0.38.17

Captured (UTC)

2026-08-11T18:56:17Z

Header height

68199363

State read at

68199362

Module store

bank

The state is read at one height and committed by the header at the next one: a Cosmos header's AppHash is the root of the state the previous block left behind. Both heights are recorded in the capture, and the capture asserts the relationship rather than assuming it.

Voting power is not validator count

The commit needs more than two thirds of the voting power, which on this set is more than 57130044 of 85695066. It is a strict inequality: exactly two thirds is not enough. These are figures about the captured set, not measurements of a run.

The 5 validators in force at height 68199363

Validator	Voting power	Share
6242446D6100FF27A850FD9DCED9512359C3A99A	43980086	51.32%
805AC0A38E0B08FA8E67E627E9781CE58897B734	41224130	48.11%
459B656975751C86D2D3E9F597A979344F1D8CFD	208362	0.24%
2574AE37BFF07C473DCD36F46FF334F54E55D97C	203101	0.24%
51FD33F85A311FD27B36A620A7B9A40BF4839533	79387	0.09%

The highlighted 2 of 5 validators carry more than the threshold between them. So a minority of validators can pass this commit, and a majority of them can fail it. Two scenarios below do exactly that.

What the proofs are about

Both proofs are checked against the header's AppHash, in two layers: the key inside the bank module's own tree, and that tree's root inside the multistore.

Present key

00 uosmo

Its value

480788050440442

Absent key

00 pf-s209a-no-such-denom

Run the verifier

Every scenario declares the verdict it expects before it runs, and the result panel prints that beside what actually happened. If the two ever disagree, this page says so.

Commit signatures and voting power

As captured The signed header and validator set exactly as they were captured. Expects: accepted One bit flipped in one signature A single bit is flipped in one validator's ed25519 signature. Nothing else is touched. Expects: rejected A majority of validators, a minority of power The largest validators are marked absent, leaving a majority of the validators by head count signing — and far less than two thirds of the voting power. Expects: rejected A minority of validators, a majority of power The mirror image: only the largest validators sign. They are a minority by head count and carry more than two thirds of the power, so the commit stands. Expects: accepted The validator set from another height The real validator set from a much earlier height of the same chain is substituted. It is a genuine set, and it is not the one this header commits to. Expects: rejected Verified against the wrong chain The same header and signatures, checked against a different chain ID. Expects: rejected

ICS-23 membership

As captured The key, its value and both proof layers exactly as captured. Expects: accepted One bit flipped in the value The proof is untouched; one bit of the value it commits to is flipped. Expects: rejected One bit flipped in the AppHash The proof and the value are untouched; one bit of the state root the header commits to is flipped. Expects: rejected

ICS-23 non-membership

As captured A key that is absent from the store, proven absent. Expects: accepted Asked about a key that exists The absence proof is asked about the key the membership proof shows a value for. A key that is present cannot be proven absent. Expects: rejected

The verifier is a separate, public Go module; this page is only the menu in front of it. It has no cosmos-sdk dependency — two direct dependencies in total.

Nothing is deployed by this demo, on any chain. It reads bytes that osmo-test-5's validators published, and checks the signatures and proofs over them.