[UPDATE PROMPTS] Migrate deprecated mode: agent frontmatter to description

[Copilot]

📝 Prompt Update

• Scope: Global
• Hierarchy Level: Level 1-4 (all prompt files)
• Target Language (if applicable): All

🎯 Changes

What Changed

Replaced deprecated mode: agent YAML frontmatter with description field across all 58 .prompt.md files:

• .github/prompts/ (14 files) — development guide descriptions
• resources/cli/codeql/ (22 files) — CLI command reference descriptions
• resources/cli/qlt/ (4 files) — QLT command reference descriptions
• languages/*/tools/dev/ (18 files) — language-specific dev guide descriptions
• .github/instructions/ (2 files) — updated instructions that referenced the old format

Also fixed an erroneous ````prompt prefix on codeql_execute_query-server2.prompt.md.

Before:

---
mode: agent
---

After:

---
description: >-
  Reference for the codeql test run command
---

Why This Change

VS Code deprecated the mode frontmatter attribute. It now emits: "The 'mode' attribute has been deprecated. Please rename it to 'agent'." Rather than blindly renaming to agent: agent, the issue asks to migrate to lightweight prompts with proper description metadata — which is the recommended frontmatter for resource/reference files that don't need to force a specific agent mode.

Issues Addressed

• Eliminates deprecation warnings in VS Code for all 58 prompt files
• Adds meaningful description metadata for better discoverability in the Copilot prompt picker

🔍 Impact

Previous Behavior

VS Code flags every .prompt.md file with a deprecation lint warning on mode: agent. No description metadata available in prompt selection UI.

New Behavior

Clean frontmatter with contextual descriptions. Each prompt file is self-describing via its description field.

🧪 Validation

• Manual testing completed
• Workflow validation performed
• No forbidden files included (no queries, tests, or analysis files)

Test Scenarios

1. Verified zero remaining mode: agent references across all .prompt.md and .instructions.md files
2. Verified all 58 .prompt.md files contain valid description frontmatter
3. Code review and CodeQL scan passed with no issues

📋 Checklist

• Only prompt system files included
• No query implementation files
• No analysis or summary files
• Documentation updated (PROMPTS.md/README.md if needed)
• Links and references validated

🔗 References

• VS Code prompt files docs
• awesome-copilot #440 — lint error on mode

---

Note: This update maintains hierarchy integrity and follows prompt system best practices.

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:

• code.visualstudio.com
  • Triggering command: /home/REDACTED/work/_temp/ghcca-node/node/bin/node /home/REDACTED/work/_temp/ghcca-node/node/bin/node --enable-source-maps /home/REDACTED/work/_temp/copilot-developer-action-main/dist/index.js (dns 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)

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📍 Connect Copilot coding agent with Jira, Azure Boards or Linear to delegate work to Copilot in one click without leaving your project management tool.

[enyil]

LGTM