> ## Documentation Index
> Fetch the complete documentation index at: https://docs.neus.network/llms.txt
> Use this file to discover all available pages before exploring further.

# Proofs

> Save a completed check and reuse it at the next gate.

A proof is the saved result of a completed check. Keep its proof ID so your app can read its current status, share it, or reuse it without repeating the full check.

The API field for the proof ID is `qHash`.

## What to store

Store the proof ID and the fields your product needs for access or display. Read the current proof before a protected action instead of rebuilding the original check.

`contentHash` identifies the checked content or artifact. It is not the proof ID.

## Storage

Proofs are private and offchain by default. A blockchain record is optional and must be requested explicitly with `options.publishToHub: true` or `targetChains`.

Wallet-signed creates can also return a portable envelope that another system can check without calling NEUS. See [Portable proofs](../learn/standards/caip-380).

## Next

* [How checks work](../verification/how-it-works)
* [Proof lifecycle](../verification/lifecycle)
* [Hosted Verify](../cookbook/auth-hosted-verify)
* [Privacy](./security-and-trust)