How to install yarn?

[rafael-unloan]

Hi, I have a workflow that requires yarn, typescript, etc. I want the agent to only finish the session once all the code compile and all the tests pass.

I've tried defining steps like this:

steps:

    - name: Setup node environment
      uses: actions/setup-node
      with:
        node-version-file: '.nvmrc'
        registry-url: https://npm.pkg.github.com/
        scope: '@my-org'
        package-manager-cache: false

    - name: Enable corepack
      shell: bash
      run: |
        corepack enable

engine: copilot

tools:
  edit:
  bash:
    - "cd:*"
    - "rg:*"
    - "git:*"
    - "corepack:*"
    - "yarn:*"
    - "pnpm:*"
    - "cat:*"
    - "ls:*"
    - "head:*"
    - "tail:*"
    - "find:*"
    - "grep:*"
    - "wc:*"
    - "sed:*"
    - "xargs:*"

safe-outputs:
  create-pull-request:
    title-prefix: "chore(feature-flag-cleanup): "
    labels: [feature-flag-cleanup, automation]
    draft: true
---

# Feature Flag Cleanup

Remove the feature flag `${{ github.event.inputs.feature_flag_key }}` from the codebase.

Jira Ticket: ${{ github.event.inputs.jira_ticket }}

Make sure all the tests pass via running `yarn root:test` before finishing this session.

## Final Step

After all changes are complete and validated, create a pull request using `safe-outputs.create-pull-request`. Do not use the GitHub CLI or API directly - the safe-outputs mechanism will handle PR creation automatically when you're done.

I can see that it successfully installs all my modules, etc.

However, when it comes to the agent actually executing the prompt, it doesn't have the environment setup. It still tries to install yarn (to no avail):

How am I supposed to do this?

[github-actions]

Assigned to @pelikhan for review. This looks like a workflow environment setup question that would benefit from maintainer guidance on how to properly configure Node.js tooling for the agent execution context.

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[github-actions]

Hi @rafael-unloan! I've assigned this to @mnkiefer who has recent experience with workflow automation. This issue involves workflow environment setup and package manager configuration, which aligns with their recent contributions.

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[github-actions]

Assigning to @dsyme based on recent contributions to workflow infrastructure and safe outputs. This issue involves workflow environment setup and node/yarn configuration for agent sessions.

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[github-actions]

Assigned to @dsyme based on recent work with workflow infrastructure and GitHub Actions integration. This issue involves runtime environment setup and how the agent interacts with pre-installed tools in GitHub Actions workflows.

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[github-actions]

Hi @rafael-unloan! Assigning this to @dsyme who has recent experience with workflow improvements and CLI functionality. The issue involves setting up the Node/Yarn environment properly for the agent execution phase, which requires understanding how the workflow steps interact with the agent container.

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[pelikhan]

You've been looking at this @Mossaka