Callstack Agent Skills is a collection of instructions that gives AI coding assistants practical knowledge for building React Native applications. Developers use it for app development, performance, navigation, testing, CI, device automation, and migrations to React Native. The catalogue entries are the project's skills, rules, and instructions for compatible coding assistants.
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/callstackincubator/agent-skillsWrote 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/rules/callstackincubator/agent-skills/agent-skills-overview)<a href="https://agentmods.dev/rules/callstackincubator/agent-skills/agent-skills-overview"><img src="https://agentmods.dev/badge/rules/callstackincubator/agent-skills/agent-skills-overview/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/rules/callstackincubator/agent-skills/agent-skills-overview"><img src="https://agentmods.dev/badge/rules/callstackincubator/agent-skills/agent-skills-overview.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 | $0.00356 | $0.00356 |
| Opus 5.5 | $0.00142 | $0.00142 |
| Sonnet 5.5 | $0.00071 | $0.00071 |
| Haiku 4.5 | $0.00036 | $0.00036 |
Grade A, and why
agent-skills-overview 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.
What it actually says
Agent skills (Callstack)
This repository uses the agentskills.io layout. Read the relevant SKILL.md first, then follow links into references/.
Skill entry points
Use the copy under skills/ when this repository is checked out; otherwise use the web view:
- react-native-best-practices — RN performance (FPS, lists, native, bundle)
- github-actions — Actions, simulators, artifacts
- upgrading-react-native — RN / Expo upgrades
- react-native-brownfield-migration — brownfield adoption
Consuming these rules in another project
If you imported this ruleset from GitHub into a different workspace, the markdown files above may not exist locally. Clone or copy the skills/ tree (see the repository README Cursor section) so paths resolve, or ask the user to add the skill files.
Workflow
Follow measure → optimize → re-measure. Prefer profiler evidence over speculative optimizations.
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 First seen · 26 lines · 356 tokens per session scan A 0b1840a025ca
agent-skills-overview is a cursor rule published in the GitHub repository callstackincubator/agent-skills (1,684 stars, last pushed 19d ago), licensed MIT. It adds 356 tokens to every session, about $0.0014 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 cursor rules, from other repositories
ponytail
Ponytail, lazy senior dev mode. Always pick the simplest solution that works.
angular-20
This rule provides comprehensive best practices and coding standards for Angular development, focusing on modern TypeScript, standalone components, signals, and performance optimizations.
dev-standard
Apache Superset development standards and guidelines for Cursor IDE.
prefer-assertions-over-defensive-checks
Prefer assertions over defensive checks when data is guaranteed to be valid.
prefer-direct-imports-over-module-mocks
Prefer extracting a testable core over vi.mock / vi.resetModules when unit tests need to reach production logic entangled with config, env, or singletons.
config-validation-and-normalization
Config validation and normalization responsibilities (defineConfig normalizes, the orm section schema validates and resolves paths, the loader reports per-section diagnostics).