agenthub · variable.set
Save Variable
Store a value under a name for the rest of the run, and read it anywhere by that name — no data edge needed to each consumer.
Why the node earns its place
The write half of the blackboard. Instead of routing one value along edges to every node that needs it, save it once; downstream nodes read it by name through their context-key fields. Data stops being trapped in the edge topology — produce once, reference everywhere.
It also forwards its input unchanged, so it drops into an existing path without breaking it: a Condition downstream still sees the original envelope, not just the saved field.
How it works at run time
- 1Take the wired value.
- 2If
pathis set, pull that nested field out of it to save — this changes only what is stored. - 3Write it into the run's variable bag under
name. - 4Forward the original input unchanged on
output.
What you wire
Inputs
- value *any
Outputs
- outputany
Configuration
| Key | Type | Default & options | What it does |
|---|---|---|---|
| name * | string | — | Variable name to store under (e.g. 'member_name'). Read it later via a *_context_key field. |
| path | string | — | Optional dotted path to pull a nested field out of the wired value to SAVE (e.g. 'record.name'). Empty saves the whole value. This only changes what's stored — the node still forwards the ORIGINAL input unchanged, so a downstream `if` on `found` still works. After a Test Run you can pick this from the observed shape. |
What usually goes wrong
Watch for this
Ordering still comes from edges. A node that reads the variable must run after this one, or it races an empty bag and reads nothing. Wire this node into the path rather than hanging it off to the side, or gate its readers behind it.
Behaviour & provenance