Borrowing it
Nothing to install: this file belongs to diillson/chatcli. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/diillson/chatcli/main/.agent/skills/testing-patterns/SKILL.mdgit clone --depth 1 https://github.com/diillson/chatcliWrote 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/diillson/chatcli/testing-patterns)<a href="https://agentmods.dev/skills/diillson/chatcli/testing-patterns"><img src="https://agentmods.dev/badge/skills/diillson/chatcli/testing-patterns/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/diillson/chatcli/testing-patterns"><img src="https://agentmods.dev/badge/skills/diillson/chatcli/testing-patterns.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 | $0.00016 | $0.00840 |
| Opus 5.5 | $0.00006 | $0.00336 |
| Sonnet 5.5 | $0.00003 | $0.00168 |
| Haiku 4.5 | $0.00002 | $0.00084 |
Grade A, and why
testing-patterns 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.
This is a copy
89% identical to testing-patterns — 4 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.
How it starts
The opening of the file, as written. The whole thing — 179 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Testing Patterns
Principles for reliable test suites.
1. Testing Pyramid
/\ E2E (Few)
/ \ Critical flows
/----\
/ \ Integration (Some)
/--------\ API, DB queries
/ \
/------------\ Unit (Many)
Functions, classes
2. AAA Pattern
| Step | Purpose |
|---|---|
| Arrange | Set up test data |
| Act | Execute code under test |
| Assert | Verify outcome |
3. Test Type Selection
When to Use Each
| Type | Best For | Speed |
|---|---|---|
| Unit | Pure functions, logic | Fast (<50ms) |
| Integration | API, DB, services | Medium |
| E2E | Critical user flows | Slow |
4. Unit Test Principles
Good Unit Tests
| Principle | Meaning |
|---|---|
| Fast | < 100ms each |
| Isolated | No external deps |
| Repeatable | Same result always |
| Self-checking | No manual verification |
| Timely | Written with code |
What to Unit Test
| Test | Don't Test |
|---|---|
| Business logic | Framework code |
| Edge cases | Third-party libs |
| Error handling | Simple getters |
5. Integration Test Principles
What to Test
| Area | Focus |
|---|---|
| API endpoints | Request/response |
| Database | Queries, transactions |
| External services | Contracts |
Setup/Teardown
| Phase | Action |
|---|---|
| Before All | Connect resources |
| Before Each | Reset state |
| After Each | Clean up |
| After All | Disconnect |
6. Mocking Principles
When to Mock
| Mock | Don't Mock |
|---|---|
| External APIs | The code under test |
| Database (unit) | Simple dependencies |
| Time/random | Pure functions |
| Network | In-memory stores |
Mock Types
| Type | Use |
|---|---|
| Stub | Return fixed values |
| Spy | Track calls |
| Mock | Set expectations |
| Fake | Simplified implementation |
7. Test Organization
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.
- 1mo ago First seen · 179 lines · 16 tokens per session scan A f229085ad979
testing-patterns is a skill published in the GitHub repository diillson/chatcli (93 stars, last pushed today), licensed Apache-2.0. It adds 16 tokens to every session and 840 once invoked, about $0.0001 per session on Opus 5.5. A static security scan graded it A with 0 findings. It is 89% identical to testing-patterns, differing in 4 lines, and is treated as a copy.
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