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SMS RFM

SMS RFM (SMS Rule Flavor Markdown) is the source text format used inside an <rc-sms> element. It is a compact, human-readable string that compiles to the SmsContentJson tree. Writing SMS RFM is far more concise than constructing SmsContentJson by hand, and it is the form the XML representation of an SMS template stores in the body of <rc-sms>.

This page describes the format conceptually — what constructs it has and how they map to the document model. For the functions that parse and serialise it, see Building programmatically.

What SMS RFM contains ​

An SMS RFM string is built from four constructs:

  1. Paragraphs — separated by blank lines.
  2. Hard breaks — forced line breaks inside a paragraph.
  3. Placeholders — dynamic values substituted at send time.
  4. Links — text that becomes a hyperlink with tracking and shortening flags.

That is the entire format. Plain text written between these constructs becomes text nodes verbatim.

Paragraphs ​

A paragraph is a block of text on consecutive lines. A blank line ends one paragraph and starts the next:

First paragraph.

Second paragraph.

See paragraph for the node reference.

Hard breaks ​

A hard break is a line break that stays inside the same paragraph. Write a backslash at the end of a line, or two trailing spaces, to insert one:

First line\
Second line — same paragraph

See hardbreak for the node reference and the distinction between hard breaks and paragraph boundaries.

Placeholders ​

A placeholder inserts a dynamic value — a subscriber field, custom field, account attribute, formatted date, fetched remote content, or system-managed link URL.

The recommended form is the ::placeholder{…} directive:

Hi ::placeholder{type="Subscriber" original="[Subscriber:FirstName]" name="First name"}!

Six token types are available: Subscriber, User, CustomField, Date, RemoteContent, and Link. The original attribute holds the backend token (in [Type:Name] format) the Rule platform substitutes at send time.

Plain-text [Type:Name] tokens belong inside the original attribute of a ::placeholder{…} directive (as shown above) or inside a URL value such as href="[Link:Unsubscribe]". The parser does also accept a bare [Type:Name] token as a backward-compatible shorthand and produces an equivalent placeholder node from it, but the ::placeholder{…} directive is the recommended form for body content because it carries the full name / value / max-length attributes the editor expects.

See placeholder for the full attribute table, the catalogue of all six token types, and per-token examples.

A link wraps a span of text in a hyperlink. The :link[…]{…} directive provides the destination URL, a tracking flag, and a URL-shortening flag:

Click :link[here]{href="https://example.com" track="true" shorten="true"} to track your order.

Inside href a plain-text [Link:…] token is the right form for system-managed URLs:

:link[Unsubscribe]{href="[Link:Unsubscribe]" track="false" shorten="false"}

See the link mark page for the full attribute reference.

A complete example ​

A short marketing message exercising all four constructs:

Hi ::placeholder{type="Subscriber" original="[Subscriber:FirstName]" name="First name"},\
your order ::placeholder{type="CustomField" original="[CustomField:Order.Id]" name="Order.Id"} has shipped.

Track it here: :link[track shipment]{href="https://example.com/track/[CustomField:Order.Id]" track="true" shorten="true"}

Reply STOP to unsubscribe.

This compiles to a three-paragraph SmsContentJson document — a greeting with a hard break and two placeholders, a tracking link, and a footer — exactly the shape described on the SMS document page.