unit-testing

Guidance for writing unit tests in React Native DevTools, a tool for inspecting React Native applications. It recommends focusing on useful tests and adding regression tests for bugs.

In plain words
What is it for?
Use it when deciding which React Native unit tests to add, remove, or revise, particularly for bug fixes and heavily mocked tests.
Why use it?
It reduces tests that only inflate coverage numbers or duplicate the implementation, while preserving checks for real failures.

Agent

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 agents/callstackincubator/rozenite/unit-testing
Clone the repo
git clone --depth 1 https://github.com/callstackincubator/rozenite
Per session 0 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 56 The whole file, excluding the scripts and references it only reads on demand.
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.

ModelPer sessionOnce invoked
Fable 5 $0.00000 $0.00056
Opus 5 $0.00000 $0.00028
Sonnet 5 $0.00000 $0.00011
Haiku 4.5 $0.00000 $0.00006

Measured today against content hash 3e5c27b6ead0, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

unit-testing 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 today.

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.

docs/agents/unit-testing.md · 7 lines

What it actually says

Unit testing

  • Skip low-ROI tests.
  • Do not add tests solely for code-coverage completeness.
  • If a test mocks roughly 80% of the implementation, reconsider or omit it.
  • For bug fixes, prefer a regression guard reproducing the original failure.
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.

  1. today First seen · 7 lines · 0 tokens per session scan A 3e5c27b6ead0

Subscribe to this mod's changes

unit-testing is an agent published in the GitHub repository callstackincubator/rozenite (653 stars, last pushed today), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 56 tokens. 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.