# Sign Messages

> Documentation index: [llms.txt](https://namera.ai/llms.txt).

Source: https://namera.ai/docs/sdk/guides/signing/sign-messages

Sign a text message with your account and an authorized session key.

Use `namera.sign()` with `type: "message"` to sign a UTF-8 string. Signing a
message does not submit a transaction.

## Before You Start [#before-you-start]

Set up [authentication](https://namera.ai/docs/sdk/authentication) and a session key installed
on **Base Sepolia**. The installation needs signature authority, and its API
signature policy must allow `message` signing.
See [Permissions](https://namera.ai/docs/sdk/permissions#message-and-typed-data-signing).

```sh
npm install @namera-ai/sdk
```

## Sign a Message [#sign-a-message]

Replace the IDs with your account and session key:

```ts title="index.ts"
import { NameraClient } from "@namera-ai/sdk";

const namera = new NameraClient({ apiKey: process.env.NAMERA_API_KEY! });
const message = "Hello from Namera";

const signed = await namera.sign({
  namespace: "eip155",
  walletId: "0199dfe1-0000-7000-8000-000000000001",
  sessionKeyId: "0199dfe1-0000-7000-8000-000000000002",
  chainId: "eip155:84532",
  type: "message",
  message,
});

if (!signed.success) throw new Error(signed.error.message);

console.log(signed.data);
```

<div className="docs-response">

```json
{
  "namespace": "eip155",
  "walletId": "0199dfe1-0000-7000-8000-000000000001",
  "chainId": "eip155:84532",
  "account": "0x1111111111111111111111111111111111111111",
  "signature": "0x0000000100111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111b",
  "type": "message"
}
```

</div>

The response values are illustrative. Use the actual `signature` returned by
your request, with the original message, account, and network.

## Verify the Signature [#verify-the-signature]

```ts title="index.ts"
const verification = await namera.verifySignature({
  namespace: "eip155",
  walletId: signed.data.walletId,
  chainId: signed.data.chainId,
  type: "message",
  message,
  signature: signed.data.signature,
});

if (!verification.success) throw new Error(verification.error.message);

console.log(verification.data);
```

<div className="docs-response">

```json
{
  "namespace": "eip155",
  "walletId": "0199dfe1-0000-7000-8000-000000000001",
  "chainId": "eip155:84532",
  "account": "0x1111111111111111111111111111111111111111",
  "valid": true,
  "type": "message"
}
```

</div>

Check `verification.data.valid`, not just `success`. These are smart-account
signatures; use [Verify Signatures](https://namera.ai/docs/sdk/guides/signing/verify-signatures)
rather than comparing a recovered EOA address.

For structured payloads, use [Sign Typed Data](https://namera.ai/docs/sdk/guides/signing/sign-typed-data).