callstack/agent-device is a toolset that lets coding agents inspect, control, debug, and verify running apps on mobile, desktop, web, and TV platforms. Developers use its CLI, MCP server, or Node.js API to test application changes on simulators, emulators, physical devices, and remote device clouds. The catalogue entries provide agent integrations and instructions for using it.
Borrowing it
Nothing to install: this file belongs to callstack/agent-device. 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/callstack/agent-device/main/AGENTS.mdgit clone --depth 1 https://github.com/callstack/agent-deviceWrote 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/callstack/agent-device/agents-md)<a href="https://agentmods.dev/instructions/callstack/agent-device/agents-md"><img src="https://agentmods.dev/badge/instructions/callstack/agent-device/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/callstack/agent-device/agents-md"><img src="https://agentmods.dev/badge/instructions/callstack/agent-device/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 | $0.00924 | $0.00924 |
| Opus 5.5 | $0.00370 | $0.00370 |
| Sonnet 5.5 | $0.00185 | $0.00185 |
| Haiku 4.5 | $0.00092 | $0.00092 |
Grade A, and why
agent-device 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 7d 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 — 64 lines — stays where its author put it; the contents beside it link to each section on GitHub.
AGENTS.md
agent-device is a CLI and daemon that automates devices and web targets.
The daemon owns sessions. Registry declarations route commands to platform runtimes.
Task routing
Read only your task's row. Follow other links only when they apply.
| When the task involves | Read |
|---|---|
| Domain vocabulary | CONTEXT.md |
| Read architecture decisions | docs/adr/README.md |
| Write or amend an ADR | docs/adr/FORMAT.md |
| Source changes, package boundaries, routing, diagnostics | docs/agents/code-ownership.md |
| Checks or a failed gate | docs/agents/testing.md |
| New or changed tests | docs/agents/test-authoring.md |
| Test audits or deletions | docs/agents/test-audit.md |
| Mutation experiments or base comparisons | docs/agents/test-experiments.md |
| Gate selection, fuzzing, or mutation harnesses | docs/agents/gates.md |
| Selector capture, polling, interaction fast paths, replay | docs/agents/selector-capture.md |
| A new or changed CLI flag | docs/agents/cli-flags.md |
| A PR to open or update | docs/agents/pull-requests.md |
| A change to review | docs/agents/review.md |
| Device-facing changes or manual device verification | docs/agents/device-verification.md |
| Issues, PRDs, or triage labels | docs/agents/issue-tracker.md, docs/agents/triage-labels.md |
| Web backend setup or diagnostics | docs/agents/web-backend.md |
A device-facing change affects live device behavior: dispatch, capture, interaction, app lifecycle, or native execution. If a daemon edit changes none of these, a device run is not required.
The versioned CLI help owns command semantics. To drive an app, start with the skill's routing card.
Working rules
- Keep edits in the requested command family or module group. Examine other platforms only when the task requires it.
- Fix a recurring failure at the owning type, registry, or construction path. Do not rebuild another owner's state.
- Use typed reasons and details for behavior. Do not match error text.
- Add compatibility or fallback behavior only on explicit request or approval. During a migration, remove superseded paths.
- Encode invariants in names, types, and boundaries. Write comments only for public APIs, tool directives, or constraints that code cannot show.
- Resolve a gate failure at the reported invariant. Do not suppress it. Do not add an allowlist to get a pass.
- Use
@agent-device/selectorsto parse and match selectors. For other shared owners, seedocs/agents/code-ownership.md. - Keep skills as routing cards. Keep
CONTEXT.mdas a glossary only. When behavior changes, update the owning help and user docs.
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.
- 7d ago Changed · +4 tokens per session 5a7bc0af7b11
- 11d ago Changed · +1 lines · +13 tokens per session 7568d74a6bf7
- 12d ago Changed · +1 lines · +61 tokens per session 4275a76db983
- 13d ago Changed · -85 lines · -1,071 tokens per session 45b936a274e1
- 14d ago Changed · +7 lines · +158 tokens per session a950a58835d2
- 15d ago Changed · +6 tokens per session 6aa6c3b9896c
- 17d ago Changed · +2 lines · +41 tokens per session 8f333142cb6e
- 25d ago Changed · +2 lines · +33 tokens per session 81906e79388d
- 1mo ago Changed · +1 lines · +27 tokens per session ac4a2c0b7ba1
- 1mo ago First seen · 135 lines · 1,652 tokens per session scan A bac876c925ff
agent-device AGENTS.md is an instructions file published in the GitHub repository callstack/agent-device (5,189 stars, last pushed today), licensed MIT. It adds 924 tokens to every session, about $0.0037 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.
Other instructions, from other repositories
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).
next.js AGENTS.md
AGENTS.md instructions for vercel/next.js, covering next.js development guide, codebase structure, monorepo overview, core package: packages/next and other important packages.
vscode oss-third-party-notices.instructions.md
Instructions for microsoft/vscode, covering vs code oss third-party-notices pipeline, architecture, pipeline flow in ci, cache eligibility and rollout and applying the notice (cutover).
langchain AGENTS.md
AGENTS.md instructions for langchain-ai/langchain, covering global development guidelines for the langchain monorepo, corridor security analysis, project architecture and context, monorepo structure and development tools & commands.
vscode copilot-instructions.md
Copilot instructions for microsoft/vscode, covering vs code copilot instructions, project overview, root folders, core architecture (src/ folder) and built-in extensions (extensions/ folder).
deepseek-harness AGENTS.md
AGENTS.md instructions for deepseek-ai/deepseek-harness, covering agents.md, pre-stable apis and released session data, repository layout, commands and host sandbox failures.