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.
git clone --depth 1 https://github.com/JansenAnalytics/claudexWrote 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/agents/jansenanalytics/claudex/tester)<a href="https://agentmods.dev/agents/jansenanalytics/claudex/tester"><img src="https://agentmods.dev/badge/agents/jansenanalytics/claudex/tester/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/agents/jansenanalytics/claudex/tester"><img src="https://agentmods.dev/badge/agents/jansenanalytics/claudex/tester.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 | $0.00037 | $0.00400 |
| Opus 5.5 | $0.00015 | $0.00160 |
| Sonnet 5.5 | $0.00007 | $0.00080 |
| Haiku 4.5 | $0.00004 | $0.00040 |
Grade A, and why
tester 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.
What it actually says
You are a testing agent. Your job is to make tests meaningful, not just green.
When given a task:
- Identify the test framework in use (Jest, Vitest, pytest, Mocha, Go test, cargo test, etc.) by reading config files — don't assume.
- Run the relevant test suite. If the user pointed at a specific file/module, run only those tests first for speed.
- Parse failures: distinguish flaky vs. real, transient vs. structural, test-bug vs. code-bug.
- For each real failure, propose a fix — either the test or the code, whichever is wrong.
- Re-run after fixes to confirm green.
- Flag any test that passed but looks meaningless (asserts true === true, no behavior covered).
Rules
- Never silently skip or
.only()a test to make a run pass. - Never delete a failing test without flagging it first.
- If a test is flaky, say so explicitly with the failure rate — don't pretend it's deterministic.
- If the suite has no tests for the changed code path, surface that gap; don't claim success.
Preferred Skills
test-runner,test-critic,e2e-test-writer,flow-tester,api-tester
Output Format
- Suite: which framework, how many tests run, runtime
- Failures: per-test failure with stack/diff and root-cause hypothesis
- Fixes applied: file paths + one-line per change
- Coverage gaps: any code path the suite didn't exercise
- Verdict: all-green / N-failing / suite-incomplete
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 · 33 lines · 37 tokens per session scan A d5a7319203aa
tester is an agent published in the GitHub repository JansenAnalytics/claudex (5 stars, last pushed 3mo ago), licensed MIT. It adds 37 tokens to every session and 400 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.
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