serve-sim is a command-line tool for serving Apple Simulator applications or files over a network, similar to how `npx serve` serves web files. It is used for headless iOS development workflows, and the catalogue entries provide agent instructions and skills for operating it.
Borrowing it
Nothing to install: this file belongs to EvanBacon/serve-sim. 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/EvanBacon/serve-sim/main/AGENTS.mdgit clone --depth 1 https://github.com/EvanBacon/serve-simWrote 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/instructions/evanbacon/serve-sim/agents-md)<a href="https://agentmods.dev/instructions/evanbacon/serve-sim/agents-md"><img src="https://agentmods.dev/badge/instructions/evanbacon/serve-sim/agents-md/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/instructions/evanbacon/serve-sim/agents-md"><img src="https://agentmods.dev/badge/instructions/evanbacon/serve-sim/agents-md.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 | $0.00983 | $0.00983 |
| Opus 5.5 | $0.00393 | $0.00393 |
| Sonnet 5.5 | $0.00197 | $0.00197 |
| Haiku 4.5 | $0.00098 | $0.00098 |
Grade A, and why
serve-sim 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 1mo 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.
How it starts
The opening of the file, as written. The whole thing — 67 lines — stays where its author put it; the contents beside it link to each section on GitHub.
- Test-driven development where possible.
- Prefer kebab-case for all TS/JS files.
- Avoid low-opacity for icons.
- Only support maintained Node.js LTS releases (currently Node 20+). Don't add
workarounds for end-of-life Node versions; rely on
ws(a dependency) rather than a globalWebSocketso the middleware works across supported runtimes.
Native build notes
- Build native changes with
bun run packages/serve-sim/build.ts. This rebuilds the bundled JS, compiled CLI, camera dylib/helper, AX settings helper, and the N-API addon atpackages/serve-sim/dist/native/serve-sim-native.node. - After changing Swift/ObjC++ native code, restart any running
serve-simprocess. The.nodeaddon is loaded once per process, so rebuilding alone does not update an already-running server. - When validating local native changes, run the rebuilt local CLI
(
node packages/serve-sim/dist/serve-sim.js ...or the compiled binary inpackages/serve-sim/dist/) rather thannpx serve-simor a globally installed binary.
E2E testing with agent-browser
If you are codex, run in the in-app Codex browser instead of using agent-browser. Only use agent-browser when developing from TUIs like Claude Code.
The serve-sim web UI streams the iOS Simulator and forwards clicks, so end-to-end
behavior can be driven from a browser with the agent-browser CLI:
- Build:
bun run packages/serve-sim/build.ts. - Boot a simulator and start the server:
node packages/serve-sim/dist/serve-sim.js --port 3399. - Drive the UI:
agent-browser open http://localhost:3399, thensnapshot,click @eN,upload input[type=file] <path>,screenshot <path>, etc. - Tap inside the simulator with
agent-browser mouse move <x> <y> && mouse down && mouse up— the canvas isn't in the AX tree, so use pixel coordinates from a screenshot.
E2E testing via the serve-sim CLI
For headless flows that don't need the browser, drive the simulator entirely
through serve-sim subcommands against a running server:
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.
- 1mo ago Changed · +6 lines · +64 tokens per session 2f478857dbe3
- 2mo ago First seen · 61 lines · 919 tokens per session scan A 5b500a004253
serve-sim AGENTS.md is an instructions file published in the GitHub repository EvanBacon/serve-sim (2,905 stars, last pushed yesterday), licensed Apache-2.0. It adds 983 tokens to every session, about $0.0039 per session on Opus 5.5. 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.
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