amirasyraf

# Native Copilot CLI extension implementation plan

## Goal and scope

Implement `github-session-warmer` as a native extension of the existing interactive Copilot CLI, following [REPORT.md](REPORT.md). Keep the stock terminal UI and attach through `joinSession()` from `@github/copilot-sdk/extension`.

Deliver cache observability first, then experimental warming using exactly:

```text
COPILOT_CACHE_WARMING

amirasyraf

# GitHub Copilot CLI Native Extension: Cache Warming and Cache Statistics

**Research report — 8 October 2026**  
**Implementation scope:** A native extension running inside the **existing interactive GitHub Copilot CLI**, with no standalone SDK client, replacement TUI, external proxy, or feature request to GitHub.  
**Background research only:** The standalone Copilot SDK and its low-level inference interception feature, isolated in **Appendix A**. It is **not** the implementation path.  
**Verification:** Public documentation and source inspected; no authenticated live Copilot CLI extension test was performed.

## Executive summary

**Chosen direction: native Copilot CLI extension only.** The extension joins the running CLI session, observes usage and lifecycle events, keeps its own timers, and submits ordinary session messages via `session.send()`; the user continues using the stock Copilot terminal UI. It does **not** start a separate Copilot runtime or act as a custom SDK client.

amirasyraf

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