Chromium is an open-source web browser project and the official GitHub mirror of its source code. It is used to build and maintain software for browsing the web, with documentation and code for products such as Chrome and Android WebView.
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.
npx skills add chromium/chromium --skill android-unit-testgit clone --depth 1 https://github.com/chromium/chromiumWrote 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/skills/chromium/chromium/android-unit-test)<a href="https://agentmods.dev/skills/chromium/chromium/android-unit-test"><img src="https://agentmods.dev/badge/skills/chromium/chromium/android-unit-test/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/skills/chromium/chromium/android-unit-test"><img src="https://agentmods.dev/badge/skills/chromium/chromium/android-unit-test.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- Snyk pass
- NVIDIA SkillSpector warn
SkillSpector: 2 findings, up to medium
These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →
- medium Prompt Injection · line 20 Large whitespace padding was detected (a block of blank lines or a long run of spaces). This can push injected instructions below or to the right of the visible area so a human reviewer never sees them while the agent still reads them. Manual review of the hidden content is recommended.Fix: Remove the large whitespace padding (blank-line blocks or long space runs) and review any content hidden below or to the right of it. Keep skill files compact and reviewable so no instructions can be
- medium Prompt Injection · line 20 Large whitespace padding was detected (a block of blank lines or a long run of spaces). This can push injected instructions below or to the right of the visible area so a human reviewer never sees them while the agent still reads them. Manual review of the hidden content is recommended.Fix: Remove the large whitespace padding (blank-line blocks or long space runs) and review any content hidden below or to the right of it. Keep skill files compact and reviewable so no instructions can be
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 | $0.00036 | $0.01555 |
| Opus 5.5 | $0.00014 | $0.00622 |
| Sonnet 5.5 | $0.00007 | $0.00311 |
| Haiku 4.5 | $0.00004 | $0.00155 |
Grade A, and why
android-unit-test 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 12d 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 — 134 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Android Unit Testing Guide
This skill provides comprehensive guidance on choosing, writing, running, and
migrating Android test cases across Chromium's three major Java test tiers
(chrome_junit_tests, chrome_public_unit_test_apk, and
chrome_public_test_apk).
1. Test Tier Hierarchy & Choosing the Right Suite
When writing or refactoring Android Java tests in Chromium, always aim for the lightest, fastest test tier that satisfies the requirements of the code being tested:
| Target Suite | Execution Environment | Best For | Key Constraints & Rules |
|---|---|---|---|
chrome_junit_tests (junit/) |
Host JVM via Robolectric (BaseRobolectricTestRunner) |
Pure Java utility methods, data structures, MVC/MVC mediators (*MediatorUnitTest.java), presenter logic, string manipulation, and mock-based testing. |
Fastest execution. No actual hardware/emulator required. Cannot execute real native NDK code or live browser profiles without shadow structures or stubs. |
chrome_public_unit_test_apk (unit_device_javatests) |
Device / Emulator (BaseJUnit4ClassRunner + @Batch(Batch.UNIT_TESTS)) |
Unit tests requiring actual Android device features (such as PackageManager checks, real layout inflating/rendering with BlankUiTestActivity, or localized JNI helper methods like CurrencyFormatter). |
Configured with is_unit_test = true: any attempts to initialize the main browser process or start ChromeTabbedActivity will explicitly fail. |
chrome_public_test_apk (javatests/) |
Device / Emulator Instrumentation (ChromeTabbedActivityTestRule, BaseJUnit4ClassRunner) |
Full end-to-end multi-component browser profile initialization, web page interactions (startOnWebPage, embeddedTestServer), and complex UI flows across Activities. |
Heaviest and slowest tier. Should be reserved exclusively for full browser activity & integration flows. |
What ships with it
1 file beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
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.
- 12d ago Changed · -14 lines 8fb9b23baa5a
- 18d ago Changed · +20 lines 155626257b0d
- 1mo ago First seen · 128 lines · 36 tokens per session scan A 10948c407d77
android-unit-test is a skill published in the GitHub repository chromium/chromium (25,059 stars, last pushed today), licensed BSD-3-Clause. It adds 36 tokens to every session and 1,555 once invoked, about $0.0001 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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