Add brag-sheet skill — turn forgotten work into review bullets

[vidhartbhatia]

Pull Request Checklist

• I have read and followed the CONTRIBUTING.md guidelines.
• I have read and followed the Guidance for submissions involving paid services.
• My contribution adds a new skill file in the correct directory.
• The file follows the required naming convention.
• The content is clearly structured and follows the example format.
• I have tested the skill with GitHub Copilot CLI.
• I have run npm start and verified that docs/README.skills.md is up to date.
• I am targeting the staged branch for this pull request.

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Description

Quick context: I previously tried submitting this as an external plugin (#1420, #1425). #1420 was rejected because the repo was in my personal account — I've since moved it to microsoft/copilot-brag-sheet. #1425 I closed myself after discovering that copilot plugin install doesn't actually load joinSession() extensions. So I'm submitting the core value as a standalone skill instead — no install required, works out of the box.

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I built this because I kept forgetting what I shipped by the time review season came around.

This skill helps turn half-remembered work into solid review notes — impact-first bullets you can drop straight into a review doc. It can pull context from git history, PRs, and Copilot CLI session logs, then group things by category (PRs, bug fixes, infra, oncall, docs, etc.).

The session log angle is the part I cared about most. I use Copilot CLI a lot, and that history is usually the missing piece when I'm trying to reconstruct a week I forgot to write down.

There's also a companion extension (copilot-brag-sheet) for automatic tracking, but the skill works fine on its own.

Trigger phrases

• "log my work" / "save to brag sheet"
• "what did I do this week"
• "backfill my work history"
• "help me prep for my review"

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Type of Contribution

• New skill file.

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By submitting this pull request, I confirm that my contribution abides by the Code of Conduct and will be licensed under the MIT License.

[github-actions]

🔍 Skill Validator Results

⚠️ Warnings or advisories found

Scope	Checked
Skills	1
Agents	1
Total	2
Severity	Count
---	---:
❌ Errors	0
⚠️ Warnings	1
ℹ️ Advisories	0

Summary

Level	Finding
ℹ️	Found 1 skill(s)
ℹ️	[brag-sheet] 📊 brag-sheet: 2,922 BPE tokens [chars/4: 2,959] (standard ~), 30 sections, 6 code blocks
ℹ️	[brag-sheet] ⚠ Skill is 2,922 BPE tokens (chars/4 estimate: 2,959) — approaching "comprehensive" range where gains diminish.
ℹ️	✅ All checks passed (1 skill(s))

Full validator output

```text Found 1 skill(s) [brag-sheet] 📊 brag-sheet: 2,922 BPE tokens [chars/4: 2,959] (standard ~), 30 sections, 6 code blocks [brag-sheet] ⚠ Skill is 2,922 BPE tokens (chars/4 estimate: 2,959) — approaching "comprehensive" range where gains diminish. ✅ All checks passed (1 skill(s)) ```

[Copilot]

Pull request overview

Adds a new brag-sheet skill to the skills/ catalog, aimed at helping developers produce impact-first accomplishment entries and backfill work history for performance reviews.

Changes:

• Introduces a new skills/brag-sheet/ skill with guidance for writing “impact-first” entries.
• Adds backfill workflows leveraging git history, Copilot CLI session-state, and GitHub PR history.
• Documents an optional integration with the external copilot-brag-sheet extension for automatic tracking.