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 agentmods add skills/st0012/ruby-skills/ruby-test-frameworksnpx skills add st0012/ruby-skills --skill ruby-test-frameworksgit clone --depth 1 https://github.com/st0012/ruby-skillsWhat 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 | $0.00061 | $0.02099 |
| Opus 5 | $0.00030 | $0.01050 |
| Sonnet 5 | $0.00012 | $0.00420 |
| Haiku 4.5 | $0.00006 | $0.00210 |
Grade A, and why
ruby-test-frameworks 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 2d 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 — 178 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Minitest vs Test-Unit Divergences
Only covers where minitest and test-unit diverge. If something isn't listed here, it works the same in both.
Assertion Naming Mismatches
Using the wrong name causes NoMethodError.
| Concept | minitest | test-unit |
|---|---|---|
| Exception | assert_raises (plural) |
assert_raise (singular) |
| Throw | assert_throws (plural) |
assert_throw (singular) |
| Collection inclusion | assert_includes (plural) |
assert_include (singular) |
| Path exists | assert_path_exists (with s) |
assert_path_exist (no s) |
| Negation pattern | refute_* (e.g. refute_nil) |
assert_not_* (e.g. assert_not_nil) |
test-unit aliases minitest names (assert_raises, refute_*, etc.), so minitest syntax works in test-unit but not vice versa.
Assertions That Only Exist in One Framework
test-unit only
| Method | Purpose |
|---|---|
assert_nothing_raised |
Passes if block doesn't raise (also added by Rails on top of minitest) |
assert_true / assert_false |
Checks for exactly true or false (not just truthy/falsy) |
assert_boolean |
Checks value is true or false |
assert_compare |
For <, <=, >, >= comparisons |
assert_raise_with_message |
Checks both exception class and message |
assert_raise_message |
Checks exception message only (any class) |
assert_raise_kind_of |
Checks exception via kind_of? instead of exact class |
assert_const_defined / assert_not_const_defined |
Check constant existence |
assert_alias_method |
Verify method aliasing |
assert_nothing_thrown |
Passes if block doesn't call throw |
assert_block |
Passes if block returns truthy |
minitest only
| Method | Purpose |
|---|---|
assert_pattern / refute_pattern |
Ruby 3+ pattern matching (in expressions) |
assert_silent |
Passes if block produces no stdout/stderr |
assert_output |
Check stdout/stderr content |
capture_io / capture_subprocess_io |
Capture output for inspection |
skip_until(y, m, d, msg) |
Skip until a date, then fail as reminder |
fail_after(y, m, d, msg) |
Pass until a date, then fail as reminder |
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.
- 2d ago First seen · 178 lines · 61 tokens per session scan A b2b9d7af7606
ruby-test-frameworks is a skill published in the GitHub repository st0012/ruby-skills (125 stars, last pushed 2mo ago), licensed MIT. It adds 61 tokens to every session and 2,099 once invoked, about $0.0003 per session on Opus 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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