Templates

Some pipe config fields take free-form text that reads from your records: an LLM prompt, an email body, a Slack message. These fields use templates. A template references input fields with {{ field }} tags and, in pipes that support it, declares new output fields with {% output %} tags.

Not every template supports outputs. prompt:run@1 requires both input and output tags. email:write@1 supports only input tags.

Tag syntax

Templates use a whitelisted subset of Liquid for input refs, secrets, constants, control flow, and output declarations.

Input refs

Form	Meaning
`{{ field }}`	Required input. Pipe fails if missing.
`{{ field \| default: "" }}`	Optional input. The editor inserts new tags this way.
`{{ user.email }}`	Dotted access. Only the head (`user`) is tracked as a dependency.
`{% if email %}{{ email }}{% endif %}`	Presence guard. Also marks `email` as optional.

A field referenced anywhere without a guard becomes required. Only bare {% if x %} and x != nil / x == nil count as guards; compound conditions like {% if a or b %} do not.

Secrets and constants

Authorization: Bearer {{ SECRETS.API_KEY }}
Promo code: {{ CONSTANTS.PROMO }}

Keys must match ^[A-Z][A-Z0-9_]*$.
Lowercase ({{ secrets.x }}) is treated as a regular input ref.
Missing secrets and constants throw at render time.
Secret values are not re-parsed as Liquid.

Control flow

Allowed: if, elsif, else, unless, for, break, continue. Max for nesting is 3. forloop.index, forloop.first, and the other loop variables are available.

Filters (whitelist)

json, escape, escape_once, default, upcase, downcase, size, join, first, last, replace, truncate, strip, newline_to_br, url_encode. Anything else throws at render time.

Not allowed

{% assign %}, {% capture %}, {% include %}, {% case %}, {% cycle %}, arithmetic and date filters, and other standard Liquid features. Disallowed tags fail at parse time.

Output declarations

In prompt-style fields, declare model outputs with {% output %}:

{% output summary, type: "string", description: "One-line summary." %}
{% output score, type: "number", description: "Confidence from 0 to 100.", required: false %}
{% output details, type: "json", schema: "ProductDetails", description: "Full product spec." %}

Arg	Required	Notes
`name`	yes	First positional. `^[a-zA-Z_][a-zA-Z0-9_]*$`.
`type`	yes	`"string"`, `"number"`, `"boolean"`, `"json"`, etc.
`description`	yes	Shown to the model.
`required`	no	`true` / `false`. Defaults to `true`.
`format`	no	For example `"email"` or `"url"`.
`schema`	no	Key into `json_schemas`; used with `type: "json"`.

{% output %} is only valid in fields that support it (for example prompt inputs). Using it elsewhere fails at save time.

Template example

Prompt config with output declarations

{
  "prompt": {
    "template": "Determine if {{ company_name }} is a good customer for my magic wand 🪄 business. {% output reason, type: \"json\", schema: \"reason\", description: \"Explain why the customer is a good prospect\" %} {% output is_good_customer, type: \"boolean\", description: \"Overall fit assessment\" %}",
    "json_schemas": {
      "reason": {
        "type": "object",
        "properties": {
          "reason": {
            "type": "string",
            "description": "A summary of why the customer is or isn't a good prospect."
          }
        }
      }
    }
  }
}

Migration from the old syntax

The previous {{ input ... }} / {{ secret ... }} / {{ output ... }} / <tag>...</tag> syntax does not auto-migrate.

Old	New
`{{ input field }}`	`{{ field }}` (required) or `{{ field \| default: "" }}` (optional)
`{{ secret api_key }}`	`{{ SECRETS.API_KEY }}`
`{{ output X type="string" description="…" }}`	`{% output X, type: "string", description: "…" %}`
`<tag>…</tag>` blocks	rewrite as `{{ … }}` refs and Liquid control flow

Next steps

Qualify & email

Templates driving an AI prompt, an email draft, and a send in one request.

Conditional runs

Run a pipe only for records that match conditions.

Templates

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