I understand that a space is required after the :.
However I tend to miss this often and end up spending a few minutes trying to figure out whats wrong, until I realize my mistake.

I.e. this is an invalid prompt with no codelens and no completions, & no real actionable error message

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mode: agent
tools:[]
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Define the tas

Suggestion: Perhaps a code action to insert the require space would be a good idea, and turn this into a warning as opposed to an error.