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 0x-Professor/Agent-Skills-Hub --skill web-api-testergit clone --depth 1 https://github.com/0x-Professor/Agent-Skills-HubWrote 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/0x-professor/agent-skills-hub/web-api-tester)<a href="https://agentmods.dev/skills/0x-professor/agent-skills-hub/web-api-tester"><img src="https://agentmods.dev/badge/skills/0x-professor/agent-skills-hub/web-api-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/skills/0x-professor/agent-skills-hub/web-api-tester"><img src="https://agentmods.dev/badge/skills/0x-professor/agent-skills-hub/web-api-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 | $0.00023 | $0.00314 |
| Opus 5 | $0.00012 | $0.00157 |
| Sonnet 5 | $0.00005 | $0.00063 |
| Haiku 4.5 | $0.00002 | $0.00031 |
Grade A, and why
web-api-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 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.
What it actually says
Web API Tester
Objective
Run endpoint-level testing against openapi.yaml and produce API quality
coverage artifacts.
Required Workflow
- Read
openapi.yamlfromweb-backend-builder. - Build API collections for Bruno or Hoppscotch.
- Optionally generate automated tests in Vitest, Jest, or pytest.
- For each endpoint test:
- happy path
- edge cases (missing fields, invalid types, max payloads)
- auth failures (
401,403) - rate limiting behavior
- Validate response contracts against OpenAPI using Zod (TS) or Pydantic (Python).
- Add frontend-backend contract tests for API call compatibility.
- Generate endpoint and edge-case coverage percentages.
- Output
api-test-report.json.
Execution
python skills/web-api-tester/scripts/api_tester.py --input <workspace> --output <out.json> --format json
References
references/tools.md
What ships with it
3 files 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 First seen · 48 lines · 23 tokens per session scan A a9c0f6129197
web-api-tester is a skill published in the GitHub repository 0x-Professor/Agent-Skills-Hub (10 stars, last pushed 6mo ago), licensed Apache-2.0. It adds 23 tokens to every session and 314 once invoked, about $0.0001 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 2026-08-31.
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