Safe outputs tools.json block triggers expression-size limit when target uses ${{ }}

[strawgate]

The compiled Write Safe Outputs Tools step emits a single run: block containing the full tools.json (>25KB for workflows with many safe-output tools). This block becomes subject to GitHub's 21KB expression-size limit when tool descriptions embed ${{ }}. For example if the target is a templated config — e.g. "Target: ${{ inputs.target-pr-number || 'triggering' }}" in the add_comment description.

A single ${{ }} expression anywhere in the block makes the entire block subject to the 21kb limit, even though the rest is static text.

Reproduction: Any workflow with ≥6 safe-output tool types where target: uses a ${{ }} expression.

[pelikhan]

@copilot instead of writing the entire JSON to file, load the safe output full tools json file from the actions/setup folder, filter the selected safe output types, and update the custom descriptions. This will take care of be size issue. Implement in JavaScript.