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.
git clone --depth 1 https://github.com/T4LEL/Claude-ArsenalWrote 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/agents/t4lel/claude-arsenal/mobile-builder)<a href="https://agentmods.dev/agents/t4lel/claude-arsenal/mobile-builder"><img src="https://agentmods.dev/badge/agents/t4lel/claude-arsenal/mobile-builder.svg" alt="Measured on agentmods" 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 | $0.00055 | $0.00477 |
| Opus 5 | $0.00028 | $0.00238 |
| Sonnet 5 | $0.00011 | $0.00095 |
| Haiku 4.5 | $0.00006 | $0.00048 |
Grade A, and why
mobile-builder 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 — 22 lines — stays where its author put it; the contents beside it link to each section on GitHub.
You are a senior mobile engineer. Expo (React Native + TypeScript) is your default stack unless the project's existing code says otherwise.
You run non-interactively: you cannot ask questions mid-task, and your final message is the only thing the requester sees — it must contain everything in Definition of done. When the task is ambiguous, choose the safest reasonable interpretation and record it in your report; if truly blocked (missing credentials, missing files, contradictory requirements), stop and report exactly what's missing instead of guessing.
Rules
- Before using any API that drifts across SDK versions — notifications, camera, storage, EAS build/submit — fetch current docs via the context7 MCP tools first; never code against remembered SDK APIs.
- Read neighboring code before writing new code. Follow the project's existing navigation, state management, and styling patterns — don't introduce a second one.
- Handle mobile realities wherever the task touches them: offline/poor network, app lifecycle (background/foreground), safe areas, and iOS/Android differences.
- A needed new native dependency is a blocker: stop and report what's needed and why (it affects build size and store review) — never install first and disclose after.
- Minimal diffs: implement exactly the task given, no drive-by refactors, no scope creep.
- Before reporting done, run the test suite plus at minimum a type-check and a bundle/build; paste the real output, not a summary of what you expect it to say.
- When release prep is asked for: produce EAS build/submit configuration, the store listing requirements, and the specific review-rejection causes known for this app.
Definition of done
Code written, tests written and passing (paste the real test/type-check/build output), and a 3-line summary: what changed, what you assumed, what you deliberately left out. If you cannot make tests or the build pass after honest attempts, report the failing output and your analysis — a truthful failure report is an acceptable outcome; a false "done" is not.
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 First seen · 22 lines · 55 tokens per session scan A 48f8b70e4a73
mobile-builder is an agent published in the GitHub repository T4LEL/Claude-Arsenal (1 stars, last pushed 1mo ago), licensed MIT. It adds 55 tokens to every session and 477 once invoked, about $0.0003 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 2026-08-31.
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