Assignment node¶
Status: Current | Last reviewed: 2026-10-07
Write to workflow variables. Supports set, append (lists), prepend, concat (strings), and increment (numbers).
Behavior¶
Write values into workflow variables. Each row picks a variable, an operator, a value mode, and a value. Template mode accepts merge templates or literals. JSONata mode evaluates the value as a JSONata expression against workflow state.
- set - overwrite the variable with the new value.
- append - push onto a list (creates the list if missing).
- prepend - unshift onto the front of a list.
- concat - string-concatenate onto the existing value.
- increment - add a numeric value (may be negative).
You can add this node from the workflow editor add-node menu when building a flow.
- Assignment writes to workflow variables. Downstream nodes reference those values with vars.
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Configuration options¶
| Option | Required | Type | Values / default | What it controls |
|---|---|---|---|---|
Assignments (bindings) |
No | array | Each row writes one workflow variable. The variable name becomes available as {{vars. |
Outputs¶
This node does not declare a typed output contract. Downstream nodes can still use values written to workflow variables or inspect the run details for the node result.
See also¶
Enable Fail on expression error (fail_on_error) when an expression is a required validation gate. An assertion or expression error then fails the workflow. With this setting off, the existing behavior assigns an empty result and continues.