vscode-ContextCompilerCopilot
VS Code extension that automatically optimises every GitHub Copilot prompt — strips VS Code injected boilerplate, trims old tool-call history, and filters irrelevant system-prompt sections — all transparently, with zero user friction.
No Python. No Docker. No separate server. Just install and go.
How it works
On activation the extension:
- Starts a lightweight HTTP proxy on
localhost:8181 (inside the extension process)
- Automatically sets
github.copilot.advanced.debug.overrideProxyUrl so VS Code Copilot routes through it
- Every Copilot request passes through the CC2 pipeline before reaching GitHub's API
- On deactivation the proxy stops and the Copilot setting is restored
VS Code Copilot → localhost:8181 (this extension) → api.githubcopilot.com
│
Pipeline:
1. Boilerplate strip (always, free)
2. Mode detection
3. Section extraction (agent mode only, uses vscode.lm)
4. History trimming (agent mode only)
Authentication: Uses VS Code's existing GitHub session — the user is already signed in for Copilot. No extra login required.
Prerequisites
- VS Code 1.95+
- GitHub Copilot subscription (already signed in)
That's it.
Install
Search "Context Compiler Copilot" in the VS Code Extensions panel, or:
ext install riteshagarwal.vscode-context-compiler-copilot
Or install from .vsix:
code --install-extension vscode-context-compiler-copilot-0.1.0.vsix
Dashboard
Once active, open these in your browser:
| Page |
URL |
Description |
| Savings Dashboard |
http://localhost:8181/dashboard |
Token savings, credits, by-mode/model tables, premium quota gauge |
| Message Inspector |
http://localhost:8181/compilation |
Before/after view of every compiled request |
| Copilot Inspector |
http://localhost:8181/copilot |
Raw input/output sent to GitHub Copilot API |
Commands
| Command |
Description |
Context Compiler: Toggle On/Off |
Enable or disable the proxy |
Context Compiler: Show Token Savings |
Quick summary in notification |
Context Compiler: Open Dashboard |
Full WebView with per-mode stats |
Settings
| Setting |
Default |
Description |
contextCompilerCopilot.enabled |
true |
Enable/disable the proxy |
contextCompilerCopilot.proxyPort |
8181 |
Local port for the embedded proxy |
contextCompilerCopilot.recentTurns |
3 |
History trimmer window |
contextCompilerCopilot.maxToolChars |
200 |
Max chars from old tool results |
contextCompilerCopilot.extractionModel |
claude-haiku-4.5 |
Model family for section extraction |
contextCompilerCopilot.logExchanges |
false |
Write JSONL exchange log (off for privacy) |
Development
cd vscode-ContextCompilerCopilot
# Install dependencies (also links the local ContextCompiler-TypeScript library)
npm install
# Build
npm run build
# Watch mode
npm run dev
# Package .vsix
npm run package
Open in VS Code and press F5 to launch the Extension Development Host.
Architecture
src/
extension.ts — Activation, deactivation, commands, config watcher
proxy-server.ts — Embedded HTTP server; orchestrates pipeline per request
llm-caller.ts — Adapts vscode.lm API into the CallLLM interface
dashboard.ts — WebView panel with token-savings stats
The pipeline logic lives in ../ContextCompiler-TypeScript (shared library).
