COP-015: Prompt File Invalid Agent Mode - GitHub Copilot

Summary

• Rule ID: COP-015
• Severity: HIGH
• Category: GitHub Copilot
• Normative Level: MUST
• Auto-Fix: Yes (safe)
• Verified On: 2026-02-13

Applicability

• Tool: github-copilot
• Version Range: unspecified
• Spec Revision: unspecified

Evidence Sources

• https://code.visualstudio.com/docs/copilot/customization/prompt-files

Test Coverage Metadata

• Unit tests: true
• Fixture tests: true
• E2E tests: false

Examples

The following examples demonstrate what triggers this rule and how to fix it.

Invalid

---
description: Refactor selected code
agent: maybe
---
Refactor the selected code.

Valid

---
description: Refactor selected code
agent: ask
---
Refactor the selected code.