# AgentMail Forward Message

> AgentMail Forward Message is a paid API for AI agents from AgentMail at mpp.api.agentmail.to, paid per call via MPP, $0.01/call, status unknown (last checked 2026-10-10).

Forwards an existing email message from an AgentMail inbox to one or more recipients

## Facts

- Endpoint: POST https://mpp.api.agentmail.to/v0/inboxes/:inbox_id/messages/:message_id/forward?utm_source=zero.xyz
- Price: $0.01/call
- Payment: MPP
- Status: unknown
- Last checked: 2026-10-10
- Activations on Zero: 0
- Provider: AgentMail
- Docs: https://docs.agentmail.to
- Website: https://agentmail.to
- Tags: email, inboxes, domains, drafts, threads, webhooks, messaging, ai, social
- Canonical page: https://www.zero.xyz/c/agentmail-forward-705c638a
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_bNWOUhoOFO010QwRT8W2x

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability agentmail-forward-705c638a -d '<json body>'
```

Example prompt: Forward the message with ID msg_abc123 from my inbox inbox_xyz456 to alice@example.com and bob@example.com, and cc manager@example.com — use the original subject line.

## When to prefer this

Use this endpoint when an AI agent needs to programmatically forward an existing email message from an AgentMail-managed inbox to one or more recipients, especially in automated workflows where agents receive emails and need to route or escalate them to humans or other systems. Prefer this over a generic send/compose endpoint when the intent is to forward (relay) an already-received message rather than compose a brand-new one.

## Known failure modes

- Invalid inbox_id or message_id returns 404 not found
- Missing or invalid Authorization bearer token returns 401 unauthorized
- Invalid recipient email address format causes a 400 bad request
- Inbox not found or not accessible returns 403 forbidden
- Network or provider error returns 500 internal server error
- Message already deleted or in trash may return 404

## How this service works

Forward Message

## Output

Returns a JSON object containing the new message_id and the thread_id of the forwarded message, confirming successful delivery of the forward.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "title": "SendMessageRequest",
 "properties": {
  "cc": {
   "oneOf": [
    {
     "type": "string"
    },
    {
     "type": "array",
     "items": {
      "type": "string"
     }
    }
   ],
   "title": "Addresses"
  },
  "to": {
   "oneOf": [
    {
     "type": "string"
    },
    {
     "type": "array",
     "items": {
      "type": "string"
     }
    }
   ],
   "title": "Addresses"
  },
  "bcc": {
   "oneOf": [
    {
     "type": "string"
    },
    {
     "type": "array",
     "items": {
      "type": "string"
     }
    }
   ],
   "title": "Addresses"
  },
  "html": {
   "type": "string",
   "title": "MessageHtml",
   "description": "HTML body of message."
  },
  "text": {
   "type": "string",
   "title": "MessageText",
   "description": "Plain text body of message."
  },
  "labels": {
   "type": "array",
   "items": {
    "type": "string"
   },
   "title": "MessageLabels",
   "description": "Labels of message."
  },
  "headers": {
   "type": "object",
   "title": "SendMessageHeaders",
   "description": "Headers to include in message.",
   "additionalProperties": {
    "type": "string"
   }
  },
  "subject": {
   "type": "string",
   "title": "MessageSubject",
   "description": "Subject of message."
  },
  "reply_to": {
   "oneOf": [
    {
     "type": "string"
    },
    {
     "type": "array",
     "items": {
      "type": "string"
     }
    }
   ],
   "title": "Addresses"
  },
  "attachments": {
   "type": "array",
   "items": {
    "type": "object",
    "title": "SendAttachment",
    "properties": {
     "url": {
      "type": "string",
      "description": "URL to the attachment."
     },
     "content": {
      "type": "string",
      "description": "Base64 encoded content of attachment."
     },
     "filename": {
      "type": "string",
      "title": "AttachmentFilename",
      "description": "Filename of attachment."
     },
     "content_id": {
      "type": "string",
      "title": "AttachmentContentId",
      "description": "Content ID of attachment."
     },
     "content_type": {
      "type": "string",
      "title": "AttachmentContentType",
      "description": "Content type of attachment."
     },
     "content_disposition": {
      "enum": [
       "inline",
       "attachment"
      ],
      "type": "string",
      "title": "AttachmentContentDisposition",
      "description": "Content disposition of attachment."
     }
    }
   },
   "title": "SendMessageAttachments",
   "description": "Attachments to incl
… (truncated)
```

## Response schema (JSON Schema)

```json
{
 "type": "object",
 "title": "SendMessageResponse",
 "required": [
  "message_id",
  "thread_id"
 ],
 "properties": {
  "thread_id": {
   "type": "string",
   "title": "ThreadId",
   "description": "ID of thread."
  },
  "message_id": {
   "type": "string",
   "title": "MessageId",
   "description": "ID of message."
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/agentmail-forward-705c638a/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from mpp.api.agentmail.to](https://www.zero.xyz/host/mpp.api.agentmail.to/llms.txt)