Add whatidid skill — Copilot impact report generator

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: shailendrahegde

docs/README.skills.md

@@ -292,6 +292,7 @@ See [CONTRIBUTING.md](../CONTRIBUTING.md#adding-skills) for guidelines on how to
 | [web-design-reviewer](../skills/web-design-reviewer/SKILL.md) | This skill enables visual inspection of websites running locally or remotely to identify and fix design issues. Triggers on requests like "review website design", "check the UI", "fix the layout", "find design problems". Detects issues with responsive design, accessibility, visual consistency, and layout breakage, then performs fixes at the source code level. | `references/framework-fixes.md`<br />`references/visual-checklist.md` |
 | [webapp-testing](../skills/webapp-testing/SKILL.md) | Toolkit for interacting with and testing local web applications using Playwright. Supports verifying frontend functionality, debugging UI behavior, capturing browser screenshots, and viewing browser logs. | `assets/test-helper.js` |
 | [what-context-needed](../skills/what-context-needed/SKILL.md) | Ask Copilot what files it needs to see before answering a question | None |
+| [whatidid](../skills/whatidid/SKILL.md) | Generate a branded HTML impact report showing what GitHub Copilot helped you accomplish — goals delivered, human effort equivalent, skills augmented, collaboration patterns, and estimation evidence grounded in peer-reviewed research. Works with any Copilot CLI or VS Code agent session. | None |
 | [winapp-cli](../skills/winapp-cli/SKILL.md) | Windows App Development CLI (winapp) for building, packaging, and deploying Windows applications. Use when asked to initialize Windows app projects, create MSIX packages, generate AppxManifest.xml, manage development certificates, add package identity for debugging, sign packages, publish to the Microsoft Store, create external catalogs, or access Windows SDK build tools. Supports .NET (csproj), C++, Electron, Rust, Tauri, and cross-platform frameworks targeting Windows. | None |
 | [winmd-api-search](../skills/winmd-api-search/SKILL.md) | Find and explore Windows desktop APIs. Use when building features that need platform capabilities — camera, file access, notifications, UI controls, AI/ML, sensors, networking, etc. Discovers the right API for a task and retrieves full type details (methods, properties, events, enumeration values). | `LICENSE.txt`<br />`scripts/Invoke-WinMdQuery.ps1`<br />`scripts/Update-WinMdCache.ps1`<br />`scripts/cache-generator` |
 | [winui3-migration-guide](../skills/winui3-migration-guide/SKILL.md) | UWP-to-WinUI 3 migration reference. Maps legacy UWP APIs to correct Windows App SDK equivalents with before/after code snippets. Covers namespace changes, threading (CoreDispatcher to DispatcherQueue), windowing (CoreWindow to AppWindow), dialogs, pickers, sharing, printing, background tasks, and the most common Copilot code generation mistakes. | None |

skills/whatidid/SKILL.md

@@ -0,0 +1,47 @@
+---
+name: whatidid
+description: "Generate a branded HTML impact report showing what GitHub Copilot helped you accomplish — goals delivered, human effort equivalent, skills augmented, collaboration patterns, and estimation evidence grounded in peer-reviewed research. Works with any Copilot CLI or VS Code agent session."
+---
+
+# What I Did (Copilot) — Impact Report Generator
+
+Generate a professional impact report from your GitHub Copilot session logs. Shows what you accomplished, quantifies the human-equivalent effort, and presents it in a branded HTML report you can share with your manager or team.
+
+## What It Does
+
+- **Harvests** session data from `~/.copilot/session-state/` (local, private)
+- **Analyses** each day's work using an AI prompt calibrated against peer-reviewed research
+- **Generates** a self-contained HTML report with:
+  - Goals accomplished with task-level detail
+  - Human effort equivalent (research-grounded estimation)
+  - Skills augmented and collaboration patterns
+  - Estimation evidence with transparent methodology
+- **Emails** the report via Outlook (optional)
+
+## Quick Start
+
+```bash
+# Clone the repo
+git clone https://github.com/microsoft/What-I-Did-Copilot.git
+cd What-I-Did-Copilot
+
+# Generate a 7-day report
+python whatidid.py --date 7D
+
+# Generate and email a 30-day report
+python whatidid.py --date 30D --email
+```
+
+## Requirements
+
+- Python 3.10+
+- GitHub CLI (`gh auth login`) for AI analysis
+- Active Copilot CLI or VS Code agent sessions
+
+## Privacy
+
+Your data stays on your machine. No telemetry, no cloud uploads. The AI analysis uses your own GitHub Models API token. No one has access to your report unless you share it.
+
+## Research Basis
+
+Effort estimates are grounded in 13 peer-reviewed sources including Alaswad et al. 2026, Cambon et al. 2023 (Microsoft Research), and the SPACE framework. See [full methodology](https://github.com/microsoft/What-I-Did-Copilot/blob/main/docs/effort-estimation-methodology.md).