Rayfin is a managed Backend-as-a-Service platform that creates and operates application backends from data models defined with TypeScript decorators. It provides databases, authentication, APIs, storage, and hosting for teams building applications. Its catalogue skill and plugin help coding agents create and work with Rayfin projects.
Borrowing it
Nothing to install: this file belongs to microsoft/rayfin. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/microsoft/rayfin/main/.github/skills/launch-vscode-extension/SKILL.mdgit clone --depth 1 https://github.com/microsoft/rayfinWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/microsoft/rayfin/launch-vscode-extension)<a href="https://agentmods.dev/skills/microsoft/rayfin/launch-vscode-extension"><img src="https://agentmods.dev/badge/skills/microsoft/rayfin/launch-vscode-extension/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/microsoft/rayfin/launch-vscode-extension"><img src="https://agentmods.dev/badge/skills/microsoft/rayfin/launch-vscode-extension.svg" alt="Reviewed on agentmods" width="80" height="20"></a>What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00083 | $0.03550 |
| Opus 5.5 | $0.00033 | $0.01420 |
| Sonnet 5.5 | $0.00017 | $0.00710 |
| Haiku 4.5 | $0.00008 | $0.00355 |
Grade A, and why
launch-vscode-extension scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 14d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
This is a copy
97% identical to launch — 3 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.
How it starts
The opening of the file, as written. The whole thing — 335 lines — stays where its author put it; the contents beside it link to each section on GitHub.
VS Code Extension Automation
Automate VS Code Insiders with the Copilot Chat extension using agent-browser. VS Code is built on Electron/Chromium and exposes a Chrome DevTools Protocol (CDP) port that agent-browser can connect to, enabling the same snapshot-interact workflow used for web pages.
Prerequisites
agent-browsermust be installed. It's available in the project's devDependencies — runnpm install. Usenpx agent-browserif it's not on your PATH, or install globally withnpm install -g agent-browser.code-insidersis required. This extension uses 58 proposed VS Code APIs and targetsvscode ^1.110.0-20260223. VS Code Stable will not activate it — you must use VS Code Insiders.- The extension must be compiled first. Use
npm run compilefor a one-shot build, ornpm run watchfor iterative development. - CSS selectors are internal implementation details. Selectors like
.interactive-input-part,.monaco-editor, and.view-lineare VS Code internals that may change across versions. If automation breaks after a VS Code update, re-snapshot and check for selector changes.
Core Workflow
- Build the extension
- Launch VS Code Insiders with the extension and remote debugging enabled
- Connect agent-browser to the CDP port
- Snapshot to discover interactive elements
- Interact using element refs
- Re-snapshot after navigation or state changes
📸 Take screenshots for a paper trail. Use
agent-browser screenshot <path>at key moments — after launch, before/after interactions, and when something goes wrong. Screenshots provide visual proof of what the UI looked like and are invaluable for debugging failures or documenting what was accomplished.Save screenshots inside
.vscode-ext-debug/screenshots/(gitignored) using a timestamped subfolder so each run is isolated and nothing gets overwritten:# Create a timestamped folder for this run's screenshots SCREENSHOT_DIR=".vscode-ext-debug/screenshots/$(date +%Y-%m-%dT%H-%M-%S)" mkdir -p "$SCREENSHOT_DIR" # Windows (PowerShell): # $screenshotDir = ".vscode-ext-debug\screenshots\$(Get-Date -Format 'yyyy-MM-ddTHH-mm-ss')" # New-Item -ItemType Directory -Force -Path $screenshotDir # Save a screenshot (path is a positional argument — use ./ or absolute paths) # Bare filenames without ./ may be misinterpreted as CSS selectors agent-browser screenshot "$SCREENSHOT_DIR/after-launch.png"
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 14d ago First seen · 335 lines · 83 tokens per session scan A 406d77d7a7ec
launch-vscode-extension is a skill published in the GitHub repository microsoft/rayfin (647 stars, last pushed yesterday), licensed MIT. It adds 83 tokens to every session and 3,550 once invoked, about $0.0003 per session on Opus 5.5. A static security scan graded it A with 0 findings. It is 97% identical to launch, differing in 3 lines, and is treated as a copy.
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