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

# Composing a message

> Send a new communication or reply to the Banco Central do Brasil through the BCB TransmitirCorreio operation.

The **Compose** page lets you transmit a new communication — or a reply — to the Banco Central do Brasil (BCB). Behind the scenes, BC Correios sends the message through the BCB `TransmitirCorreio` operation, so you never need to handle the underlying SOAP/XML protocol.

## Accessing Compose

***

Open Compose from the [Inbox](/en/lerian-console/reporter-console/bc-correios-inbox) by clicking the **New message** button, or from **Reply** on a mail detail page.

<Note>
  Compose requires the `mails:post` permission. With read-only access, you see the form with a read-only banner and a disabled **Send** button.
</Note>

## Message fields

***

| Field           | Required | Description                                                                                                                                                                                             |
| :-------------- | :------- | :------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
| **Subject**     | Yes      | The subject line of the communication.                                                                                                                                                                  |
| **Destination** | No       | The destination unit at the BCB. Leave blank to use the tenant default. Common units are suggested as you type (for example DEINF, SECRE, GABIN, DEPIN, DESIG, DEORF), but the field accepts free text. |
| **Content**     | Yes      | The message body (up to 10,000 characters). A live character counter is shown.                                                                                                                          |
| **Keywords**    | No       | Comma-separated tags to classify the message. Maximum of 10 keywords, 100 characters each.                                                                                                              |

## Replying to a message

***

When you start Compose from a mail's **Reply** action, the subject is pre-filled with `Re: <original subject>` and the page shows which message you are replying to. The reply is linked to the original mail so the conversation stays traceable.

## Sending

***

1. Fill in at least the **Subject** and **Content**.
2. Optionally set a **Destination** and **Keywords**.
3. Click **Send message**.

On success, BC Correios confirms the transmission and returns you to the Inbox. The sent communication then appears in the [Sent](/en/lerian-console/reporter-console/bc-correios-folders) folder.

<Warning>
  If you navigate away with unsaved changes, BC Correios asks you to confirm before discarding the draft.
</Warning>

<Note>
  Every transmission is recorded in the [Audit](/en/lerian-console/reporter-console/bc-correios-audit) trail as a `Mail sent` event for compliance evidence.
</Note>