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/sigistry/marketplaceWrote 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/plugins/sigistry/marketplace/api-contract-keeper)<a href="https://agentmods.dev/plugins/sigistry/marketplace/api-contract-keeper"><img src="https://agentmods.dev/badge/plugins/sigistry/marketplace/api-contract-keeper/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/plugins/sigistry/marketplace/api-contract-keeper"><img src="https://agentmods.dev/badge/plugins/sigistry/marketplace/api-contract-keeper.svg" alt="Reviewed on agentmods" width="80" height="20"></a>Grade A, and why
api-contract-keeper 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
{
"name": "api-contract-keeper",
"version": "1.0.0",
"description": "Keeps your API and its spec in sync: detects and fixes OpenAPI/GraphQL spec-vs-code drift, hardens endpoints with request validation, RFC 9457 error envelopes and idempotency, guards against breaking changes, and audits job-queue reliability.",
"author": {
"name": "Sigistry API Contract Keeper",
"url": "https://github.com/Sigistry/marketplace/tree/main/plugins/api-contract-keeper"
},
"license": "MIT"
}
What it installs
The manifest is a name and a version. 4 skills, 3 commands, 2 agents travel with it, and installing the plugin installs all of them — 503 tokens a session between them. Each is measured on its own page, and each can be installed alone.
- Skill error-envelope A 99 tokens
- Skill idempotency-patterns A 106 tokens
- Skill job-reliability A 129 tokens
- Skill openapi-drift A 106 tokens
- Command harden-endpoint A 25 tokens
- Command spec-sync A 21 tokens
- Command version-guard A 17 tokens
- Agent drift-reconciler A 0 tokens
- Agent queue-doctor A 0 tokens
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 · 11 lines scan A 65e7086ffcf9
api-contract-keeper is a plugin published in the GitHub repository sigistry/marketplace (3 stars, last pushed 3d ago), licensed MIT. Its token cost is not measured: this kind of file is read by the harness, not the model. 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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