---
title: Sim Mailer
description: Send emails to your workspace and let Sim handle them as tasks.
---

import { Callout } from 'fumadocs-ui/components/callout'
import { FAQ } from '@/components/ui/faq'

Sim Mailer gives your workspace a dedicated email address. Forward or send emails to it and Sim will process them as tasks — reading the subject, body, and any attachments, then replying to the thread with the result.

This means you can interact with Sim directly from your email client without switching apps.

## Getting Started

1. Navigate to **Settings** → **Inbox**
2. Toggle the inbox on
3. Optionally choose a custom address prefix (e.g., `acme` → `acme@mothership.sim.ai`)
4. Copy your inbox address and start sending emails

If you skip the custom prefix, one is generated automatically.

<Callout type="info">
  Changing your address creates a new inbox. The old address stops working immediately.
</Callout>

## What You Can Send

Write your email like you would to a colleague. The subject and body become the task prompt.

**Attachments are fully supported.** Images, PDFs, and documents (up to 10 MB each) are read by Sim and displayed inline in the conversation — image attachments show as previews, just like when you upload them directly in the chat.

| Good email | Why it works |
|------------|-------------|
| "Summarize the attached PDF and list action items" | Clear task with an attachment |
| "What's in this image?" with a photo attached | Sim reads and describes the image |
| "Draft a reply to this forwarded thread" | Uses the email body as context |

## Allowed Senders

Only authorized senders can create tasks. Emails from anyone else are automatically rejected.

- **Workspace members** are allowed by default — no setup needed
- **External senders** can be added manually with an optional label for easy identification

External senders are email addresses that can create inbox tasks. They are not the same as external workspace members, who have workspace access in Sim without joining your organization.

Manage your allowed senders list in **Settings** → **Inbox** → **Allowed Senders**.

## Tracking Tasks

Every email becomes a task you can track in **Settings** → **Inbox**:

- **Search** by subject, sender, or body content
- **Filter** by status to find what you need
- **Click** any completed or failed task to jump to the full conversation

### Task Statuses

| Status | Meaning |
|--------|---------|
| **Received** | Email accepted, queued for processing |
| **Processing** | Sim is actively working on it |
| **Completed** | Done — the result was sent as an email reply |
| **Failed** | Something went wrong during execution |
| **Rejected** | Email blocked (sender not allowed, automated sender, or rate limit exceeded) |

## Conversations

Each email task creates a conversation in your workspace. You can continue the conversation from the Sim chat interface, and any follow-up emails in the same thread are linked to the same conversation.

<FAQ items={[
  { question: "Can I use my own email domain?", answer: "Not currently. All inbox addresses use the @mothership.sim.ai domain. You can customize the prefix (e.g., acme@mothership.sim.ai) but not the domain itself." },
  { question: "What happens if I send from an unauthorized email?", answer: "The email is automatically rejected. Only workspace members and manually added external senders can create tasks." },
  { question: "Is there a size limit for attachments?", answer: "Yes, each attachment can be up to 10 MB. Images, PDFs, and common document formats are supported." },
  { question: "Can I reply to Sim's email responses?", answer: "Yes. Replies in the same email thread are linked to the original conversation, so you can continue the interaction from your email client." },
  { question: "How long does it take to process an email?", answer: "Most emails are processed within a few seconds. Emails with large attachments or complex tasks may take slightly longer." },
  { question: "Can multiple people in my workspace use the same inbox?", answer: "Yes. All workspace members can send to the shared inbox address. Each email creates its own task and conversation." },
]} />
