agentmods.dev

testing

testing is a skill for Claude Code from holoviz-dev/holoviz-skills. It costs 34 tokens per session (826 once invoked), scanned A, original, BSD-3-Clause.

A testing guide for HoloViz Python packages, including practices for writing tests and checking edge cases. Edge cases are unusual inputs such as empty data, missing values, or reversed ranges.

In plain words
What is it for?
Use it when writing or reviewing tests, checking coverage, testing user interfaces, or examining inputs such as NaN values, dates, duplicates, and unsorted data.
Why use it?
It helps catch incorrect results, silent data loss, and unexpected errors before code is submitted for review.

Skill for Claude Code

Written for Claude Code: shipped in a Claude Code plugin.

Part of the holoviz plugin — 14 skills shipped together

not rated 5repo changed 1mo ago A scan 34 tokens original BSD-3-Clause

Good fit Use it when writing or reviewing tests, checking coverage, testing user interfaces, or examining inputs such as NaN values, dates, duplicates, and unsorted data.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/holoviz-dev/holoviz-skills/testing
View source ↗ holoviz-dev/holoviz-skills holoviz-dev.github.io
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.

Any agent
npx skills add holoviz-dev/holoviz-skills --skill testing
Clone the repo
git clone --depth 1 https://github.com/holoviz-dev/holoviz-skills

Made for: Claude Code.

Or install holoviz, the plugin that ships this one along with the rest of its 14 skills.

Wrote 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.

agentmods badge for testing

README.md
[![agentmods](https://agentmods.dev/badge/skills/holoviz-dev/holoviz-skills/testing/github.svg)](https://agentmods.dev/skills/holoviz-dev/holoviz-skills/testing)
Your own site
<a href="https://agentmods.dev/skills/holoviz-dev/holoviz-skills/testing"><img src="https://agentmods.dev/badge/skills/holoviz-dev/holoviz-skills/testing/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.

agentmods 80×15 button for testing

Your own site · 80×15
<a href="https://agentmods.dev/skills/holoviz-dev/holoviz-skills/testing"><img src="https://agentmods.dev/badge/skills/holoviz-dev/holoviz-skills/testing.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 34 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 826 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
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 5.1 $0.00034 $0.00826
Opus 5.5 $0.00014 $0.00330
Sonnet 5.5 $0.00007 $0.00165
Haiku 4.5 $0.00003 $0.00083

Measured 1mo ago against content hash 3413371ff5f3, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

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 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.

contributing-to-holoviz/skills/testing/SKILL.md · 68 lines

How it starts

The opening of the file, as written. The whole thing — 68 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Testing

This skill covers testing patterns and edge cases specific to HoloViz repositories.

Contents

General Guidelines

  • Run tests via pixi. Check pixi.toml for tasks (e.g. pixi run test-unit, pixi run test-ui).
  • New tests must fail on main before submitting, since a test that passes without the fix doesn't test the fix.
  • Write tests from the issue or the expected behavior, not from what the new code does. A test written to match the implementation checks the author's assumptions, so it can pass on the very bug it was meant to catch. Agents tend to write this kind of test for their own code.
  • Never change a test's expected value just to make it pass. Change it only after confirming the new output is correct, and say why in the PR, since editing the expectation to match wrong output hides the regression the test caught.
  • UI tests require the --ui flag.
  • Only create a new test file if no existing file is a good fit, so tests for one module stay in one place and the next contributor finds them.
  • Cover the lines you add; exercise new behavior, don't just import it.

Edge Cases and Logical Errors

  • Identify logical errors and edge cases in the changed code. Trace branching logic and boundary conditions to find inputs that could produce wrong results, silent data loss, or unexpected exceptions.
  • Test for NaN and datetime types (np, pd) — these are common edge cases across HoloViz that are easy to miss.
  • Also probe (where the logic branches on them): empty/single-element inputs, duplicate/colliding labels, negative/reversed values, unsorted input.
  • Parameterize tests when the same logic is exercised with different inputs.
  • Name tests for intent. Put what the test covers and why — including any issue link — in the function docstring, not a leading # comment: the docstring travels with the test in pytest -v output. Reserve # for a genuinely non-obvious step in the body, and skip comments that just restate what the test does.

Read the full file on GitHub · 68 lines

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. 1mo ago Changed · +2 lines 3413371ff5f3
  2. 2mo ago First seen · 66 lines · 34 tokens per session scan A 68db8858be06

Subscribe to this mod's changes

testing is a skill published in the GitHub repository holoviz-dev/holoviz-skills (5 stars, last pushed 2d ago), licensed BSD-3-Clause. It adds 34 tokens to every session and 826 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 2026-08-31.

Testing
Related

testing compared with skills from other repositories

testing next to 6 skills from other repositories
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testingholoviz-dev/holoviz-skillsSkill52d agoBSD-3-ClauseA34Claude Code
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local-ai-agentsmicrosoft/ai-agents-for-beginnersSkill79k4d agoMITA200Claude Code, Codex
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