[API reference](https://evolu.dev/docs/api-reference) › [@evolu/common](https://evolu.dev/docs/api-reference/common) › [local‑first/Protocol](https://evolu.dev/docs/api-reference/common/local-first/Protocol) › ProtocolHeader

Defined in: [packages/common/src/local-first/Protocol.ts:358](https://github.com/evoluhq/evolu/blob/e7144e2bbe9069362b62dec1b64a8aa922b8f1b0/packages/common/src/local-first/Protocol.ts#L358)

Parsed protocol header for supported protocol messages.

## Extends

- [`Typed`](https://evolu.dev/docs/api-reference/common/Type/interfaces/Typed)\<`"ProtocolHeader"`\>

## Properties

<a id="messagetype"></a>

### messageType

```ts
readonly messageType: MessageType;
```

Defined in: [packages/common/src/local-first/Protocol.ts:361](https://github.com/evoluhq/evolu/blob/e7144e2bbe9069362b62dec1b64a8aa922b8f1b0/packages/common/src/local-first/Protocol.ts#L361)

---

<a id="ownerid"></a>

### ownerId

```ts
readonly ownerId: string & Brand<"Id"> & Brand<"OwnerId">;
```

Defined in: [packages/common/src/local-first/Protocol.ts:360](https://github.com/evoluhq/evolu/blob/e7144e2bbe9069362b62dec1b64a8aa922b8f1b0/packages/common/src/local-first/Protocol.ts#L360)

---

<a id="type"></a>

### type

```ts
readonly type: "ProtocolHeader";
```

Defined in: [packages/common/src/Type.ts:3492](https://github.com/evoluhq/evolu/blob/e7144e2bbe9069362b62dec1b64a8aa922b8f1b0/packages/common/src/Type.ts#L3492)

#### Inherited from

[`Typed`](https://evolu.dev/docs/api-reference/common/Type/interfaces/Typed).[`type`](https://evolu.dev/docs/api-reference/common/Type/interfaces/Typed#type)

---

<a id="version"></a>

### version

```ts
readonly version: 1;
```

Defined in: [packages/common/src/local-first/Protocol.ts:359](https://github.com/evoluhq/evolu/blob/e7144e2bbe9069362b62dec1b64a8aa922b8f1b0/packages/common/src/local-first/Protocol.ts#L359)