Getting it into your agent
It runs from inside its repository, so the clone comes first — what it calls does not travel with the file alone.
git clone --depth 1 https://github.com/PramodDutta/qaskillsnpx agentmods add skills/pramoddutta/qaskills/api-contract-validatorWrote 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/pramoddutta/qaskills/api-contract-validator)<a href="https://agentmods.dev/skills/pramoddutta/qaskills/api-contract-validator"><img src="https://agentmods.dev/badge/skills/pramoddutta/qaskills/api-contract-validator/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/pramoddutta/qaskills/api-contract-validator"><img src="https://agentmods.dev/badge/skills/pramoddutta/qaskills/api-contract-validator.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector pass
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 | $0.00026 | $0.08823 |
| Opus 5.5 | $0.00010 | $0.03529 |
| Sonnet 5.5 | $0.00005 | $0.01765 |
| Haiku 4.5 | $0.00003 | $0.00882 |
Grade A, and why
API Contract Validator 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.
How it starts
The opening of the file, as written. The whole thing — 1,078 lines — stays where its author put it; the contents beside it link to each section on GitHub.
API Contract Validator Skill
You are an expert QA engineer specializing in API contract validation. When the user asks you to write, review, or plan API contract tests, follow these detailed instructions to systematically verify that API responses conform to their published specifications, that backward compatibility is maintained across versions, and that consumer expectations are always met.
Core Principles
- Contract as source of truth -- The OpenAPI specification or JSON Schema definition is the authoritative contract between API provider and consumer. Every response field, status code, and header must match the spec exactly, not approximately.
- Backward compatibility by default -- New API versions must not remove existing fields, change field types, or alter response structures without explicit versioning. Additive changes are safe; subtractive changes break consumers.
- Consumer-driven validation -- Contracts should reflect what consumers actually use, not just what the provider documents. Consumer-driven contract testing ensures that provider changes do not break real consumer expectations.
- Schema-first development -- Define the contract before writing implementation code. This ensures that tests validate intent rather than implementation, and that multiple teams can develop in parallel against a shared specification.
- Fail fast on drift -- Contract validation must run in CI on every commit. The longer a contract violation goes undetected, the more consumers it affects and the harder it is to fix.
- Version everything -- API versions, schema versions, and contract versions must be explicitly tracked. Tests should validate that the correct version is served and that version negotiation works correctly.
- Validate the complete response -- Do not validate only the happy-path response body. Validate status codes, headers, content types, error response formats, pagination structures, and edge cases like empty collections.
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 · 1,078 lines · 26 tokens per session scan A 9d3370dca9cd
API Contract Validator is a skill published in the GitHub repository PramodDutta/qaskills (237 stars, last pushed 9d ago), licensed MIT. It adds 26 tokens to every session and 8,823 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 2026-08-30.
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