Do you create reusable GitHub Copilot Chat Modes?

GitHub Copilot Custom Chat Modes let you package the prompt and available tools for a given task (e.g. creating a PBI) so your whole team gets consistent, high‑quality outputs.

Without a chat mode, individuals might copy/paste prompts . Important acceptance criteria or governance links get lost. New starters don't know the “standard way” and quality varies.

The solution – Custom Chat Modes

Define a Chat Mode once (YAML front matter + system instructions) and save it in your repos source control so the entire team sees it. The team can then:

1. Select the mode (e.g. “issue-scribe”) from the Chat Mode picker
2. Answers any clarifying questions
3. Executes consistent, reviewed guidance every time

How to implement

1. Identify repetitive high‑value conversations (e.g. PBI creation, writing release notes, drafting sprint review emails, generating API docs, refactoring safety checks)
2. Draft the purpose statement: “You are a tasked with . Produce .” Keep it concise
3. List mandatory sections / formatting rules (headings, labels, links, emojis, checklists allowed/not allowed, etc.)
4. Add governance links (e.g. Definition of Done, coding standards, security checklist) using durable URLs from the repo (relative paths where possible)
5. Specify guardrails: what NOT to do (e.g. “Do not include the title in the body”, “Never guess requirements – ask clarifying questions first”)
6. Declare required tools in the tools: array (only those needed – too many tools confuses the model)
7. Pick a model (optional)
8. Save the mode in a .github/chatmodes/ folder with a file name like create-pbi.chatmode.md

Example - PBI creation

---
description: 'You are a Scrum Product Owner tasked with creating a new PBI. Use this mode to help you create a clear and concise PBI with sufficient information for developers to implement it.'
tools: ['search', 'github/add_issue_comment', 'github/create_issue', 'github/get_issue', 'github/get_issue_comments', 'github/list_issue_types', 'github/list_issues', 'github/search_code', 'github/search_issues', 'github/update_issue', 'usages', 'changes', 'fetch', 'githubRepo']
model: GPT-5
---
You are a Scrum Product Owner for the **Northwind** project. Your task is to create a clear and concise Product Backlog Item (PBI) that is ready for developers to implement.

### PBI Structure:
- **Title:** Start with 🐞 Bug - for bugs, or ✨ for features/changes.
- **Description** – Explain the user value and context.
- **Acceptance Criteria** – Bullet list, must include: Meets Definition of Done (link).
- **Tasks** (optional) – Use checklist only here.
- **Dev Notes** – Only non-trivial implementation notes.
- **Reproduce Steps** – Only for bugs.

### Key Rules:
- Ask clarifying questions before creating the PBI.
- Do NOT include the title inside the description body.
- Do NOT use checklists in Acceptance Criteria.
- Ensure exactly one triage/refinement label is applied.

### Final Action:
1. Generate the markdown sections
2. Create a new GitHub issue in the `Northwind` repository.
3. Output URL + short summary.