Variables

Syntax

Wrap a variable in double curly braces anywhere a field accepts text: {{params.id}}. Click the variable button next to a field to see the variables that are available there and insert one without typing. There are three roots:

Variable	What it is	Example
`{{params.<name>}}`	A parameter the AI passed when calling the tool	`{{params.email}}`
`{{env.<KEY>}}`	An environment secret of the server	`{{env.API_TOKEN}}`
`{{nodes.<step-id>.output}}`	The output of an earlier step	`{{nodes.query_1.output}}`

After the root you can read nested values with .field and list items with [index]:

{{nodes.query_1.output[0].email}}
{{nodes.http_request_1.output.data.items[2].title}}
{{params.address.city}}

Missing values don’t throw errors: if output[0] doesn’t exist, the variable is simply empty.

Whole value or inside text

How a variable is used depends on whether it is the entire field or part of a longer text:

Field value	Result
`{{nodes.query_1.output}}`	The original value: an array stays an array, a number stays a number
`Hello {{params.name}}!`	Text. Objects and arrays are inserted as JSON text
`42`, `true`, `null`, `[1, 2]`	Plain values without variables are read as JSON when possible

In URL fields, variables that come after other text are URL-encoded automatically. With https://api.example.com/search?q={{params.query}}, a query like red shoes becomes red%20shoes. In JSON body fields, put variables inside string values. A value that is only a variable keeps its original type:

{
  "name": "{{params.name}}",
  "age": "{{params.age}}",
  "tags": "{{nodes.transform_1.output.tags}}"
}

Here age is sent as a number and tags as an array when the source values have those types.

Rules

A step can only use the output of a step that runs before it, meaning a step connected earlier in the chain. Otherwise the field shows Step <id> must run before this step.
Referencing a step that doesn’t exist shows Step <id> does not exist.
Any other text inside {{ }} shows Unknown variable {{...}}. Only params, env and nodes.<id>.output are allowed; there are no functions or operators inside variables.
Prefer secret fields such as Bearer token secret or the Database step credentials over {{env.KEY}} in free text, so secrets never appear in URLs or logs by accident.

Run the workflow once before you write variables for a step. The inspector then shows each step’s real output, so you can see exactly which fields are available.

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Syntax

Whole value or inside text

Rules

​Syntax

​Whole value or inside text

​Rules

Syntax

Whole value or inside text

Rules