What is emulate AGENTS.md?

Repository instructions for Vercel Labs’ emulate project, including its package manager, command-line examples, dependency rules, and writing conventions. A package manager installs and manages the project’s software dependencies.

Use them when installing dependencies, writing user-facing commands, checking package versions, and following the project’s formatting and language rules.

They prevent common setup mistakes, such as using the wrong package manager or accidentally invoking a shell command instead of the project’s executable. They also keep documentation and output consistent.

emulate AGENTS.md — Instructions file by vercel-labs

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods

npx agentmods add instructions/vercel-labs/emulate/agents-md

Clone the repo

git clone --depth 1 https://github.com/vercel-labs/emulate

Made for: Codex, OpenCode.

Per session 1,091 This file is loaded in full into every session.

When invoked 1,091 The same file — it is already loaded in full.

Security scan A 0 findings. Scan, not verified.

Origin original No closer match found in the catalogue.

Token cost

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	$0.01091	$0.01091
Opus 5	$0.00545	$0.00545
Sonnet 5	$0.00218	$0.00218
Haiku 4.5	$0.00109	$0.00109

Measured 2d ago against content hash b7f7b1e50d63, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

emulate AGENTS.md 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 2d 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.

AGENTS.md · 87 lines

How it starts

The opening of the file, as written. The whole thing — 87 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Agents

Package Manager

Use pnpm for all package management commands (not npm or yarn).

Exception: End-user install instructions should use npm (e.g. npx emulate, npm install emulate) since npm is universal.

CLI Invocation

emulate is a zsh built-in command (it sets shell emulation mode). Running bare emulate in zsh invokes the shell built-in, not the npm binary. Always use npx emulate in user-facing CLI examples, docs, skills, help output, and post-command messages. The only exception is when emulate appears as a subprocess argument to another tool (e.g. portless github.emulate emulate start), where the binary is resolved by the parent process rather than the shell.

Dependencies

Always check for the latest npm version when adding dependencies. Use pnpm add <package> (without version) to get the latest, or verify with npm view <package> version first.

No Emojis

Do not use emojis anywhere in this repository (code, comments, output, docs).

Dashes

Never use -- as a dash in prose, comments, or user-facing output. Use an em dash (\u2014) when a dash is needed, but prefer rephrasing to avoid dashes entirely. The only exception is CLI flags (e.g. --port).

Emulator UI Design System

All emulator UIs (inspector pages, OAuth flows, checkout pages, inboxes, etc.) must use the shared design system in packages/@emulators/core/src/ui.ts. Never write inline HTML with custom <style> tags or standalone <!DOCTYPE html> templates in individual emulator packages.

Use the appropriate shared render function for each page type:

renderCardPage for centered card layouts (OAuth sign-in, email detail, checkout)
renderErrorPage for error states
renderSettingsPage for sidebar + main content layouts (OAuth app settings, Slack inspector)
renderInspectorPage for tabbed data dashboards (AWS inspector)
renderFormPostPage for OAuth form_post auto-submit redirects
renderUserButton for user selection buttons in OAuth flows

Read the full file on GitHub · 87 lines

Changes

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.

2d ago First seen · 87 lines · 1,091 tokens per session scan A b7f7b1e50d63

Subscribe to this mod's changes

emulate AGENTS.md is an instructions file published in the GitHub repository vercel-labs/emulate (1,621 stars, last pushed yesterday), licensed Apache-2.0. It adds 1,091 tokens to every session, about $0.0055 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

DevOps and cloud

spec-kit AGENTS.md

AGENTS.md instructions for github/spec-kit, covering agents.md, about spec kit and specify, quickstart — add a new integration in 5 steps, integration architecture and integrationmanifest — file tracking.

github/spec-kit · 7,104 tokens

vscode buildNext.instructions.md

Working notes and architecture documentation for the new esbuild-based build system in build/next. Use when making changes to the new build pipeline (transpile/bundle commands, NLS plugin, source-map handling, resource copying, or self-hosting watch tasks).

microsoft/vscode · 6,785 tokens

emulate AGENTS.md