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

# Digital signatures

> Create keys, sign data, and request signatures from verified parties

Neuro signatures bind data or agreements to cryptographic keys and, where required, Legal Identities.

<Warning>
  No end-to-end signature example is currently available. Confirm the key algorithm, signing request, returned fields, and compatible Neuron version before using signatures in production.
</Warning>

## Start here

* [Create a cryptographic key](/neuron-api/guides/creating-cryptographic-keys).
* Read [Keys and signatures](/platform/keys-and-signatures) before choosing where keys are managed.
* Use [Agreements](/build/agreements/overview) for multi-party contract signing.
* Check the [cryptography](/neuron-api/api-reference/cryptography/overview) and [contract](/neuron-api/api-reference/contracts/overview) operations.

## Choose the workflow

| Outcome                           | Start with                                                                    |
| --------------------------------- | ----------------------------------------------------------------------------- |
| Create a signing key              | [Creating cryptographic keys](/neuron-api/guides/creating-cryptographic-keys) |
| Sign application data             | `POST /Agent/Legal/SignData` in the Agent API reference                       |
| Request another party's signature | `POST /Agent/Legal/PetitionSignature` in the Agent API reference              |
| Sign a smart contract             | [Agreements](/build/agreements/overview)                                      |

## Show users what they sign

When using the Agent API, the application acts through the agent exposed by the Neuron's HTTP API. This is distinct from a direct XMPP client that holds and manages its own private keys.

Never present a signature action without showing the exact human-readable or binary content being authorized. Record the returned identifier, signer, algorithm, timestamp, and validation result required by the supported response schema.