The HALO Tool Call is a dialog node that invokes a HALO tool from within a running dialog. Unlike adding a tool as an output to an Event or Article (which is terminal — control passes back to the NLP flow after the tool runs), the HALO Tool Call is a mid-flow step: the dialog continues executing from the next connected node after the tool completes.
This makes it analogous to the API Callout node — same input mapping, same success and error handler pattern — but routing to a HALO tool instead of an arbitrary external endpoint. No URL or authentication configuration is needed; the tool is selected from the linked HALO profile.
A linked HALO profile is required. Tools are drawn from that profile. Use Open HALO Studio from the Analytics screen or navigate to HALO Studio directly to create or manage tools.
Adding a HALO Tool Call Node
In the dialog canvas, open the node picker and select HALO Tool Call from the Functional section. Place it in your dialog flow and connect it to the preceding and following nodes.
Configuration
Tool
Select the HALO tool to invoke from the HALO tool dropdown. The tool's description is shown to help confirm the right selection. Required input parameters are determined by the selected tool.
Map Input Parameters
Each tool defines its own input parameters. Required parameters are marked with an asterisk. For each parameter, either select a conversation variable (whose current value is passed in) or type a static value directly.
Success Handler
Defines how to store the tool's output when it succeeds. Add one or more output mappings using + Add. Each mapping has:
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Type — Payload: stores the tool's full JSON response in the selected conversation variable.
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Type — Property: extracts a specific field from the response using a JMESPath expression and stores that value in the selected conversation variable.
After a successful tool execution, the dialog continues from the node connected to the success output.
Error Handler
Defines what happens if the tool call fails:
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Stop dialog (toggle on) — the dialog terminates immediately on error.
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Error Output — connect a node to this output to handle the error gracefully within the dialog flow (e.g. send an error message and continue).
Difference from "Add tool" Outputs
The HALO Tool Call node and the "Add tool" output on Events/Articles/Dialog output nodes both invoke a HALO tool, but they behave differently after the tool runs:
|
|
HALO Tool Call node |
"Add tool" output |
|---|---|---|
|
Where it lives |
Mid-flow dialog step |
Output on Event, Article, or Dialog output node |
|
After tool completes |
Dialog continues to next node |
Control returns to AI Cloud NLP flow |
|
Error handling |
Stop dialog toggle + Error Output node |
Not configurable |
|
Use when |
Tool call is part of a larger dialog sequence |
Tool call is the final action for this content match |