microsoft / microsoft/pxt-microbit

[Code Evaluation] Evaluation fails for JavaScript and Python projects with "Unable to evaluate" error

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#6,986 0 comments 0 reactions 1 assignee View on GitHub

@srietkerk is already working on this.

Since Jul 2, 2026.

code eval tool P2
Dominant language
TypeScript
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Description

Describe the bug
When evaluating JavaScript or Python projects in the Code Evaluation tool, the system fails and displays an error message (Unable to evaluate – An unexpected error occurred).

Steps to reproduce the behavior:

  1. Navigate to MakeCode Code Evaluation.
  2. Enter a JavaScript or Python Share Project link, e.g. JavaScript: https://makecode.microbit.org/S38180-65764-35865-76506.
  3. Create or select a checklist containing one or more evaluation criteria.
  4. Click Evaluate and observe the checklist state.

Actual behavior
Evaluation shows: “Unable to evaluate – An unexpected error occurred” for all checklist items.

Expected behavior
JavaScript and Python projects should be evaluated successfully according to checklist criteria.

Screenshots
Image

Additional context
1.OS: Windows 11 25H2
2.Browser: Chrome, Edge, and Firefox
3.makecode.microbit.org version: 8.1.28
4.Microsoft MakeCode version: 12.3.24

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