Output of Variable Aggregator (Grouping) Not Properly Resolved in Custom External Tool within Workflow

[yjc980121]

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Dify version

0.15.0

Cloud or Self Hosted

Self Hosted (Docker)

Steps to reproduce

When using the output of a variable aggregator (grouping) as input parameters for a custom external tool in a workflow, the variables are not being resolved correctly. This results in abnormal query parameters. Specifically:

The output of the variable aggregator is not resolved to its actual value as expected.

The custom external tool receives unresolved variable names instead of their actual values.

Abnormal query parameters cause the external tool to malfunction.

Steps to Reproduce:

Configure a variable aggregator (grouping) in the workflow and set its output variables.

Reference the output variables of the variable aggregator as input parameters in a custom external tool.

Run the workflow and observe the input parameters received by the custom external tool.

Notice that the input parameters remain unresolved variable names instead of actual values.

It is unclear whether Chatflow exhibits similar behavior. It is recommended to investigate this as well.

the dsl file 钉钉日志.zip

✔️ Expected Behavior

The output of the variable aggregator should be resolved to actual values and passed as input parameters to the custom external tool.

❌ Actual Behavior

The output of the variable aggregator remains unresolved, causing the custom external tool to receive unresolved variable names.