Email tools

`sendmock_email_check`

HTML and CSS support across email clients. List-Unsubscribe and one-click unsubscribe checks. Check every link in the message. Score the message with the spam rules.

Toolset email.

Read only

Input	Type	Description
kindrequired	string	Picks what to do. `html`: HTML and CSS support across email clients. `unsubscribe`: List-Unsubscribe and one-click unsubscribe checks. `links`: Check every link in the message. `spam`: Score the message with the spam rules.One of: `html`, `unsubscribe`, `links`, `spam`Example: `html`
email_idrequired	string	The email's ID, from `GET /api/v1/emails`.Example: `01JB7T9Q2R5W8X3Y6Z1A4B7C9D`

Example call

{
  "name": "sendmock_email_check",
  "arguments": {
    "kind": "html",
    "email_id": "01JB7T9Q2R5W8X3Y6Z1A4B7C9D"
  }
}

Result: HtmlCheckReport | ListUnsubscribeReport | LinkCheckResult[] | SpamCheckReport

API: kind: htmlGET/api/v1/emails/{emailId}/html-checkkind: unsubscribeGET/api/v1/emails/{emailId}/list-unsubscribekind: linksPOST/api/v1/emails/{emailId}/link-checkkind: spamPOST/api/v1/emails/{emailId}/spam-check
CLI: sendmock email check <emailId> html, sendmock email check <emailId> unsubscribe, sendmock email check <emailId> links, sendmock email check <emailId> spam
In the app: Mail > open email > Checks; Mail > open email > Headers

`sendmock_email_click`

Record a click on one of the email's links and fire email.clicked.

Toolset email.

Input	Type	Description
email_idrequired	string	The email's ID, from `GET /api/v1/emails`.Example: `01JB7T9Q2R5W8X3Y6Z1A4B7C9D`
urlrequired	string	The link that was clicked; one of the email's links (`extracted.links`).Example: `https://app.test/verify?token=abc123`
source	string	Who clicked it: `ui` (a link in the preview), `manual` (Simulate click) or `api` (a script). Defaults to `api`.One of: `ui`, `manual`, `api`Example: `api`
user_agent	string	The browser or client that clicked, kept in the click history. The UI sends its own.Example: `Mozilla/5.0 (Macintosh; Intel Mac OS X 14_5)`
webhook_endpoint_ids	string[]	Send this action's webhooks to exactly these endpoints (IDs from `GET /api/v1/webhooks/endpoints`) instead of the ones the rules pick; an empty list sends none. Leave it out to let the rules decide.Example: `["01JB7T9Q2RENDPOINT00000000"]`
webhook_requests	WebhookRequestEdit[]	Payloads edited for this action, by endpoint: each body is sent as written instead of the rendered one and signed over those bytes. Leave it out to send the rendered payloads.Example: `[{"endpoint_id":"01JB7T9Q2RENDPOINT00000000","event_type":"email.bounced","body":"{\"type\":\"email.bounced\",\"data\":{\"reason\":\"edited\"}}","headers":{"x-tenant":"acme"}}]`

Example call

{
  "name": "sendmock_email_click",
  "arguments": {
    "email_id": "01JB7T9Q2R5W8X3Y6Z1A4B7C9D",
    "url": "https://app.test/verify?token=abc123",
    "source": "api",
    "user_agent": "Mozilla/5.0 (Macintosh; Intel Mac OS X 14_5)"
  }
}

Result: nothing

API: POST/api/v1/emails/{emailId}/clicks
CLI: sendmock email click <emailId>
In the app: Mail > open email > click a link in the preview, or Simulate click

`sendmock_email_clicks`

Every recorded click on the email's links, newest first.

Toolset email.

Read only

Input	Type	Description
email_idrequired	string	The email's ID, from `GET /api/v1/emails`.Example: `01JB7T9Q2R5W8X3Y6Z1A4B7C9D`

Example call

{
  "name": "sendmock_email_clicks",
  "arguments": {
    "email_id": "01JB7T9Q2R5W8X3Y6Z1A4B7C9D"
  }
}

Result: EmailClickRecord[]

API: GET/api/v1/emails/{emailId}/clicks
CLI: sendmock email clicks <emailId>
In the app: Mail > open email > Timeline (clicked entries)

`sendmock_email_delete`

Delete one email.

Toolset email.

Destructive
Idempotent

Input	Type	Description
email_idrequired	string	The email's ID, from `GET /api/v1/emails`.Example: `01JB7T9Q2R5W8X3Y6Z1A4B7C9D`

Example call

{
  "name": "sendmock_email_delete",
  "arguments": {
    "email_id": "01JB7T9Q2R5W8X3Y6Z1A4B7C9D"
  }
}

Result: nothing

API: DELETE/api/v1/emails/{emailId}
CLI: sendmock email delete <emailId>
In the app: Mail > open email > Delete

`sendmock_email_delete_all`

Delete every email, or only those that match the filters.

Toolset email.

Destructive
Idempotent

Input	Type	Description
query	string	Search text; supports from:, to: and tag: prefixes.Example: `to:[email protected] reset`
from	string	Sender contains.Example: `[email protected]`
to	string	A recipient contains.Example: `[email protected]`
tag	string	Has this tag.Example: `signup`
is_unread	boolean	Only unread.Example: `true`
has_attachment	boolean	Only with attachments.Example: `true`
source	string	How it arrived: smtp, sendmail, native_api, verify, simulated, or an email provider's key, e.g. sendgrid.Example: `smtp`
direction	string	Outbound from your app or inbound to it.One of: `outbound`, `inbound`Example: `outbound`
project	string	Only this project's emails (its key); every project's when not set.Example: `shop`

Example call

{
  "name": "sendmock_email_delete_all",
  "arguments": {
    "query": "to:[email protected] reset",
    "from": "[email protected]"
  }
}

Result: nothing

API: DELETE/api/v1/emails
CLI: sendmock email delete-all --yes
In the app: Mail > Delete all

`sendmock_email_forward`

Forward as the recipient; the copy arrives as inbound email.

Toolset email.

Input	Type	Description
email_idrequired	string	The email's ID, from `GET /api/v1/emails`.Example: `01JB7T9Q2R5W8X3Y6Z1A4B7C9D`
torequired	string	Where the email is forwarded, e.g. your app's inbound address.Example: `[email protected]`
body	string	A note above the forwarded message.Example: `Can you look at this one?`
from	string	Who forwards; defaults to the original recipient.Example: `[email protected]`
subject	string	Defaults to `Fwd: <original subject>`.Example: `Fwd: Your invoice`
include_original	boolean	Adds the original below a "Forwarded message" block (default true).Example: `true`
include_attachments	boolean	Forwards the original attachments too (default true).Example: `true`
webhook_endpoint_ids	string[]	Send this action's webhooks to exactly these endpoints (IDs from `GET /api/v1/webhooks/endpoints`) instead of the ones the rules pick; an empty list sends none. Leave it out to let the rules decide.Example: `["01JB7T9Q2RENDPOINT00000000"]`
webhook_requests	WebhookRequestEdit[]	Payloads edited for this action, by endpoint: each body is sent as written instead of the rendered one and signed over those bytes. Leave it out to send the rendered payloads.Example: `[{"endpoint_id":"01JB7T9Q2RENDPOINT00000000","event_type":"email.bounced","body":"{\"type\":\"email.bounced\",\"data\":{\"reason\":\"edited\"}}","headers":{"x-tenant":"acme"}}]`

Example call

{
  "name": "sendmock_email_forward",
  "arguments": {
    "email_id": "01JB7T9Q2R5W8X3Y6Z1A4B7C9D",
    "to": "[email protected]",
    "body": "Can you look at this one?",
    "from": "[email protected]"
  }
}

Result: EmailDetail

API: POST/api/v1/emails/{emailId}/forward
CLI: sendmock email forward <emailId>
In the app: Mail > open email > Forward

`sendmock_email_get`

One email with bodies, headers, attachments and extracted codes.

Toolset email.

Read only

Input	Type	Description
email_idrequired	string	The email's ID, from `GET /api/v1/emails`.Example: `01JB7T9Q2R5W8X3Y6Z1A4B7C9D`

Example call

{
  "name": "sendmock_email_get",
  "arguments": {
    "email_id": "01JB7T9Q2R5W8X3Y6Z1A4B7C9D"
  }
}

Result: EmailDetail

API: GET/api/v1/emails/{emailId}
CLI: sendmock email show <emailId>
In the app: Mail > open email

`sendmock_email_inbound`

Create an incoming email from fields or raw MIME; fires email.inbound.

Toolset email.

Input	Type	Description
from	string	The sender, as an address or `Name <address>`.Example: `Sam <[email protected]>`
to	string[]	The recipients, usually your app's inbound address.Example: `["[email protected]"]`
subject	string	The subject line.Example: `Order arrived damaged`
text	string	The plain-text body.Example: `The box was crushed, can I get a replacement?`
html	string	The HTML body.Example: `<p>The box was crushed, can I get a replacement?</p>`
raw	string	A whole message (RFC 5322); when set, the other fields are ignored.Example: `From: [email protected] To: [email protected] Subject: Hi Hello`
webhook_endpoint_ids	string[]	Send this action's webhooks to exactly these endpoints (IDs from `GET /api/v1/webhooks/endpoints`) instead of the ones the rules pick; an empty list sends none. Leave it out to let the rules decide.Example: `["01JB7T9Q2RENDPOINT00000000"]`
webhook_requests	WebhookRequestEdit[]	Payloads edited for this action, by endpoint: each body is sent as written instead of the rendered one and signed over those bytes. Leave it out to send the rendered payloads.Example: `[{"endpoint_id":"01JB7T9Q2RENDPOINT00000000","event_type":"email.bounced","body":"{\"type\":\"email.bounced\",\"data\":{\"reason\":\"edited\"}}","headers":{"x-tenant":"acme"}}]`

Example call

{
  "name": "sendmock_email_inbound",
  "arguments": {
    "from": "Sam <[email protected]>",
    "to": [
      "[email protected]"
    ]
  }
}

Result: NativeSendResult

API: POST/api/v1/emails/inbound
CLI: sendmock email inbound
In the app: Mail > Import .eml > Incoming to your app

`sendmock_email_latest`

The newest email to a recipient.

Toolset email.

Read only

Input	Type	Description
torequired	string	The recipient address.Example: `[email protected]`
subject	string	Subject contains.Example: `Reset your password`
project	string	Only this project's emails (its key); every project's when not set.Example: `shop`

Example call

{
  "name": "sendmock_email_latest",
  "arguments": {
    "to": "[email protected]",
    "subject": "Reset your password",
    "project": "shop"
  }
}

Result: EmailDetail

API: GET/api/v1/emails/latest
CLI: sendmock email latest --to <address>
In the app: Mail > search to:

`sendmock_email_list`

Stored emails, newest first, with search and filters.

Toolset email; also answers as sendmock_email_search.

Read only

Input	Type	Description
cursor	string	The next_cursor of the previous page.Example: `01JB7T9Q2R5W8X3Y6Z1A4B7C9D`
limit	integer	Items per page, 1 to 200 (default 50).Example: `50`
query	string	Search text; supports from:, to: and tag: prefixes.Example: `to:[email protected] reset`
from	string	Sender contains.Example: `[email protected]`
to	string	A recipient contains.Example: `[email protected]`
tag	string	Has this tag.Example: `signup`
is_unread	boolean	Only unread.Example: `true`
has_attachment	boolean	Only with attachments.Example: `true`
source	string	How it arrived: smtp, sendmail, native_api, verify, simulated, or an email provider's key, e.g. sendgrid.Example: `smtp`
direction	string	Outbound from your app or inbound to it.One of: `outbound`, `inbound`Example: `outbound`
project	string	Only this project's emails (its key); every project's when not set.Example: `shop`

Example call

{
  "name": "sendmock_email_list",
  "arguments": {
    "cursor": "01JB7T9Q2R5W8X3Y6Z1A4B7C9D",
    "limit": 50
  }
}

Result: PageOf_EmailSummary

API: GET/api/v1/emails
CLI: sendmock email list
In the app: Mail

`sendmock_email_mime`

The MIME tree of the message.

Toolset email.

Read only

Input	Type	Description
email_idrequired	string	The email's ID, from `GET /api/v1/emails`.Example: `01JB7T9Q2R5W8X3Y6Z1A4B7C9D`

Example call

{
  "name": "sendmock_email_mime",
  "arguments": {
    "email_id": "01JB7T9Q2R5W8X3Y6Z1A4B7C9D"
  }
}

Result: MimePart

API: GET/api/v1/emails/{emailId}/mime
CLI: sendmock email mime <emailId>
In the app: Mail > open email > MIME

`sendmock_email_open`

Record an open and fire email.opened.

Toolset email.

Input	Type	Description
email_idrequired	string	The email's ID, from `GET /api/v1/emails`.Example: `01JB7T9Q2R5W8X3Y6Z1A4B7C9D`
source	string	Who opened it: `ui` (the SendMock UI), `manual` (a person marking it) or `api` (a script). Defaults to `api`.One of: `ui`, `manual`, `api`Example: `api`
user_agent	string	The browser or client that opened it, kept in the open history. The UI sends its own.Example: `Mozilla/5.0 (Macintosh; Intel Mac OS X 14_5)`
webhook_endpoint_ids	string[]	Send this action's webhooks to exactly these endpoints (IDs from `GET /api/v1/webhooks/endpoints`) instead of the ones the rules pick; an empty list sends none. Leave it out to let the rules decide.Example: `["01JB7T9Q2RENDPOINT00000000"]`
webhook_requests	WebhookRequestEdit[]	Payloads edited for this action, by endpoint: each body is sent as written instead of the rendered one and signed over those bytes. Leave it out to send the rendered payloads.Example: `[{"endpoint_id":"01JB7T9Q2RENDPOINT00000000","event_type":"email.bounced","body":"{\"type\":\"email.bounced\",\"data\":{\"reason\":\"edited\"}}","headers":{"x-tenant":"acme"}}]`

Example call

{
  "name": "sendmock_email_open",
  "arguments": {
    "email_id": "01JB7T9Q2R5W8X3Y6Z1A4B7C9D",
    "source": "api",
    "user_agent": "Mozilla/5.0 (Macintosh; Intel Mac OS X 14_5)"
  }
}

Result: nothing

API: POST/api/v1/emails/{emailId}/open
CLI: sendmock email open <emailId>
In the app: Mail > open email (opening it fires the open)

`sendmock_email_opens`

Every recorded open of the email, oldest first.

Toolset email.

Read only

Input	Type	Description
email_idrequired	string	The email's ID, from `GET /api/v1/emails`.Example: `01JB7T9Q2R5W8X3Y6Z1A4B7C9D`

Example call

{
  "name": "sendmock_email_opens",
  "arguments": {
    "email_id": "01JB7T9Q2R5W8X3Y6Z1A4B7C9D"
  }
}

Result: OpenRecord[]

API: GET/api/v1/emails/{emailId}/opens
CLI: sendmock email opens <emailId>
In the app: Mail > open email > Timeline (opened entries)

`sendmock_email_release`

Send the email on through the allowlisted relay.

Toolset email.

Input	Type	Description
email_idrequired	string	The email's ID, from `GET /api/v1/emails`.Example: `01JB7T9Q2R5W8X3Y6Z1A4B7C9D`
to	string[]	Who receives it on the real SMTP server; empty sends to the original recipients. Every address must match the release allowlist.Example: `["[email protected]"]`

Example call

{
  "name": "sendmock_email_release",
  "arguments": {
    "email_id": "01JB7T9Q2R5W8X3Y6Z1A4B7C9D",
    "to": [
      "[email protected]"
    ]
  }
}

Result: nothing

API: POST/api/v1/emails/{emailId}/release
CLI: sendmock email release <emailId>
In the app: Mail > open email > Release to real SMTP

`sendmock_email_reply`

Reply as the recipient; the reply arrives as inbound email.

Toolset email.

Input	Type	Description
email_idrequired	string	The email's ID, from `GET /api/v1/emails`.Example: `01JB7T9Q2R5W8X3Y6Z1A4B7C9D`
body	string	The reply text, above the quoted original; empty or left out sends no text of its own.Example: `Thanks, that fixed it!`
from	string	Who replies; defaults to the original recipient.Example: `[email protected]`
subject	string	Defaults to `Re: <original subject>`.Example: `Re: Ticket #318 updated`
reply_all	boolean	Also sends to the other original recipients, in Cc.Example: `false`
include_original	boolean	Quotes the original below an "On ... wrote:" line (default true).Example: `true`
webhook_endpoint_ids	string[]	Send this action's webhooks to exactly these endpoints (IDs from `GET /api/v1/webhooks/endpoints`) instead of the ones the rules pick; an empty list sends none. Leave it out to let the rules decide.Example: `["01JB7T9Q2RENDPOINT00000000"]`
webhook_requests	WebhookRequestEdit[]	Payloads edited for this action, by endpoint: each body is sent as written instead of the rendered one and signed over those bytes. Leave it out to send the rendered payloads.Example: `[{"endpoint_id":"01JB7T9Q2RENDPOINT00000000","event_type":"email.bounced","body":"{\"type\":\"email.bounced\",\"data\":{\"reason\":\"edited\"}}","headers":{"x-tenant":"acme"}}]`

Example call

{
  "name": "sendmock_email_reply",
  "arguments": {
    "email_id": "01JB7T9Q2R5W8X3Y6Z1A4B7C9D",
    "body": "Thanks, that fixed it!",
    "from": "[email protected]"
  }
}

Result: EmailDetail

API: POST/api/v1/emails/{emailId}/reply
CLI: sendmock email reply <emailId>
In the app: Mail > open email > Reply, Reply all

`sendmock_email_send`

Native send: JSON with optional base64 attachments.

Toolset email.

Input	Type	Description
fromrequired	string	The sender, as an address or `Name <address>`.Example: `Shop <[email protected]>`
torequired	string[]	The recipients.Example: `["[email protected]"]`
cc	string[]	Copy recipients.Example: `["[email protected]"]`
bcc	string[]	Hidden copy recipients; stored with the email but not in its headers.Example: `["[email protected]"]`
subjectrequired	string	The subject line.Example: `Your order #1042 has shipped`
text	string	The plain-text body. Send `text`, `html` or both.Example: `Hi Sam, your order is on its way.`
html	string	The HTML body. Send `text`, `html` or both.Example: `<p>Hi Sam, your order is <b>on its way</b>.</p>`
headers	object	Extra headers, by name.
tags	string[]	Tags to file the email under in Mail.Example: `["orders"]`
attachments	NativeSendAttachment[]	Files to attach.Example: `[{"filename":"invoice-1042.pdf","content":"JVBERi0xLjQKJcfsj6IK","content_type":"application/pdf","content_id":"logo"}]`

Example call

{
  "name": "sendmock_email_send",
  "arguments": {
    "from": "Shop <[email protected]>",
    "to": [
      "[email protected]"
    ],
    "subject": "Your order #1042 has shipped",
    "cc": [
      "[email protected]"
    ],
    "bcc": [
      "[email protected]"
    ]
  }
}

Result: NativeSendResult

API: POST/api/v1/send
CLI: sendmock email send
In the app: Settings > Connection > Send this request

`sendmock_email_send_raw`

Store a raw message as sent by your app, as the sendmail shim does.

Toolset email.

Input	Type	Description
contentrequired	string	The raw request body (message/rfc822). Text as is; base64 for binary content.Example: `From: [email protected] To: [email protected] Subject: Hello Hi!`

Example call

{
  "name": "sendmock_email_send_raw",
  "arguments": {
    "content": "From: [email protected]\r\nTo: [email protected]\r\nSubject: Hello\r\n\r\nHi!"
  }
}

Result: NativeSendResult

API: POST/api/v1/send/raw
CLI: sendmock sendmail
In the app: Mail > Import .eml > Sent by your app

`sendmock_email_simulate`

Simulate a delivery outcome such as a bounce or complaint.

Toolset email.

Input	Type	Description
email_idrequired	string	The email's ID, from `GET /api/v1/emails`.Example: `01JB7T9Q2R5W8X3Y6Z1A4B7C9D`
eventrequired	string	The delivery event to simulate; it is added to the timeline and fires its webhook.One of: `delivered`, `deferred`, `bounced`, `complained`, `unsubscribed`Example: `bounced`
bounce_type	string	For `bounced` only: a hard bounce (the address does not exist) or a soft one (try again later).One of: `hard`, `soft`Example: `hard`
webhook_endpoint_ids	string[]	Send this action's webhooks to exactly these endpoints (IDs from `GET /api/v1/webhooks/endpoints`) instead of the ones the rules pick; an empty list sends none. Leave it out to let the rules decide.Example: `["01JB7T9Q2RENDPOINT00000000"]`
webhook_requests	WebhookRequestEdit[]	Payloads edited for this action, by endpoint: each body is sent as written instead of the rendered one and signed over those bytes. Leave it out to send the rendered payloads.Example: `[{"endpoint_id":"01JB7T9Q2RENDPOINT00000000","event_type":"email.bounced","body":"{\"type\":\"email.bounced\",\"data\":{\"reason\":\"edited\"}}","headers":{"x-tenant":"acme"}}]`

Example call

{
  "name": "sendmock_email_simulate",
  "arguments": {
    "email_id": "01JB7T9Q2R5W8X3Y6Z1A4B7C9D",
    "event": "bounced",
    "bounce_type": "hard",
    "webhook_endpoint_ids": [
      "01JB7T9Q2RENDPOINT00000000"
    ]
  }
}

Result: nothing

API: POST/api/v1/emails/{emailId}/simulate
CLI: sendmock email simulate <emailId> <event>
In the app: Mail > open email > Simulate

`sendmock_email_timeline`

Delivery events: received, delivered, opened, bounced.

Toolset email.

Read only

Input	Type	Description
email_idrequired	string	The email's ID, from `GET /api/v1/emails`.Example: `01JB7T9Q2R5W8X3Y6Z1A4B7C9D`

Example call

{
  "name": "sendmock_email_timeline",
  "arguments": {
    "email_id": "01JB7T9Q2R5W8X3Y6Z1A4B7C9D"
  }
}

Result: EmailTimelineEntry[]

API: GET/api/v1/emails/{emailId}/timeline
CLI: sendmock email timeline <emailId>
In the app: Mail > open email > Timeline

`sendmock_email_update`

Mark read or unread, or change tags.

Toolset email; also answers as sendmock_email_tag.

Idempotent

Input	Type	Description
email_idrequired	string	The email's ID, from `GET /api/v1/emails`.Example: `01JB7T9Q2R5W8X3Y6Z1A4B7C9D`
is_read	boolean	Marks the email as read (true) or unread (false).Example: `true`
tags	string[]	Replaces the email's tags; an empty list removes them all.Example: `["signup","qa"]`

Example call

{
  "name": "sendmock_email_update",
  "arguments": {
    "email_id": "01JB7T9Q2R5W8X3Y6Z1A4B7C9D",
    "is_read": true,
    "tags": [
      "signup",
      "qa"
    ]
  }
}

Result: EmailSummary

API: PATCH/api/v1/emails/{emailId}
CLI: sendmock email update <emailId>
In the app: Mail > open email > Mark as read, tags

`sendmock://emails/{emailId}/mime/{partId}`

Download one MIME part, decoded, by its position in the MIME tree.

Resource, read as application/octet-stream.

Parameter	Type	Description
emailIdrequired	string	The email's ID, from `GET /api/v1/emails`.Example: `01JB7T9Q2R5W8X3Y6Z1A4B7C9D`
partIdrequired	string	The part's position in the MIME tree, as `GET /emails/{emailId}/mime` numbers it, e.g. `1.2`.Example: `1.2`

API: GET/api/v1/emails/{emailId}/mime/{partId}
CLI: sendmock email mime-part <emailId> <partId>
In the app: Mail > open email > MIME, download a part

`sendmock://emails/{emailId}/raw`

The raw message source.

Resource, read as message/rfc822.

Parameter	Type	Description
emailIdrequired	string	The email's ID, from `GET /api/v1/emails`.Example: `01JB7T9Q2R5W8X3Y6Z1A4B7C9D`

API: GET/api/v1/emails/{emailId}/raw
CLI: sendmock email raw <emailId>
In the app: Mail > open email > Source, download .eml

`sendmock://emails/{emailId}/attachments/{attachmentIndex}`

Download one attachment.

Resource, read as application/octet-stream.

Parameter	Type	Description
emailIdrequired	string	The email's ID, from `GET /api/v1/emails`.Example: `01JB7T9Q2R5W8X3Y6Z1A4B7C9D`
attachmentIndexrequired	integer	Position of the file in the email's `attachments`, starting at 0.Example: `0`

API: GET/api/v1/emails/{emailId}/attachments/{attachmentIndex}
CLI: sendmock email attachments <emailId> <attachmentIndex>
In the app: Mail > open email > Attachments

`sendmock://emails/{emailId}/parts/{attachmentIndex}/thumbnail`

A preview image of an attachment.

Resource, read as image/*.

Parameter	Type	Description
emailIdrequired	string	The email's ID, from `GET /api/v1/emails`.Example: `01JB7T9Q2R5W8X3Y6Z1A4B7C9D`
attachmentIndexrequired	integer	Position of the file in the email's `attachments`, starting at 0.Example: `0`

API: GET/api/v1/emails/{emailId}/parts/{attachmentIndex}/thumbnail
CLI: sendmock email thumbnail <emailId> <attachmentIndex>
In the app: Mail > open email > Attachments (thumbnails)