Add default value to engine field in included_file_schema.json

[Copilot]

The engine field had inconsistent schema metadata: main_workflow_schema.json specified "default": "copilot" while included_file_schema.json omitted it, breaking IDE autocomplete and developer expectations.

Changes

• Added "default": "copilot" to the engine property in included_file_schema.json
• Updated description to match main workflow schema format

Both schemas now have identical default metadata, aligning with runtime behavior where GetDefaultEngine() returns Copilot when no engine is specified.

"engine": {
  "description": "AI engine configuration for included files. Defaults to 'copilot'.",
  "default": "copilot",
  "$ref": "#/$defs/engine_config"
}

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• https://api.github.com/user
  • Triggering command: /usr/bin/gh gh api user --jq .login ithub-script/git/ref/tags/v8 remote.origin.url repository(owner: $owner, name: $name) { hasDiscussionsEnabled } } -unreachable=faltail t /home/REDACTED/go/pkg/mod/golang.oxterm-color gh api /ref/tags/v8 --jq /usr/bin/gh runs/20260104-01gcc -buildtags 7956060/b380/vet-x gh (http block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
• Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)

Original prompt

---

This section details on the original issue you should resolve

<issue_title>[plan] Standardize engine default value across schemas</issue_title>
<issue_description>## Objective

Determine whether included files should have a default engine value and update included_file_schema.json accordingly for consistency.

Context

The engine field has inconsistent default values:

• main_workflow_schema.json specifies "default": "copilot"
• included_file_schema.json has no default value specified

This creates inconsistent schema metadata that affects IDE autocomplete and developer understanding.

Approach

1. Review how included files inherit or override engine settings from main workflows
2. Check if there's intentional design reasoning for no default in included files
3. Either:
   • Option A: Add "default": "copilot" to included_file_schema.json properties.engine
   • Option B: Document why included files intentionally omit the default value
4. Update schema or add documentation comment explaining the decision

Files to Modify

• pkg/parser/schemas/included_file_schema.json - Add default or $comment explaining omission

Acceptance Criteria

• Decision documented on whether included files should have default engine
• If yes: Default value added to included_file_schema.json
• If no: Comment added explaining why default is intentionally omitted
• Consistency achieved between schemas (either both have default or documented reason for difference)
  Related to [plan] Fix schema consistency issues found in analysis #8804

AI generated by Plan Command for discussion #8801

Comments on the Issue (you are @copilot in this section)

• Fixes [plan] Standardize engine default value across schemas #8807

---

💬 We'd love your input! Share your thoughts on Copilot coding agent in our 2 minute survey.