Borrowing it
Nothing to install: this file belongs to bhf/st-k8s. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/bhf/st-k8s/master/.github/agents/expert-nextjs-developer.agent.mdgit clone --depth 1 https://github.com/bhf/st-k8sWrote 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/bhf/st-k8s/expert-nextjs-developer)<a href="https://agentmods.dev/agents/bhf/st-k8s/expert-nextjs-developer"><img src="https://agentmods.dev/badge/agents/bhf/st-k8s/expert-nextjs-developer/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/bhf/st-k8s/expert-nextjs-developer"><img src="https://agentmods.dev/badge/agents/bhf/st-k8s/expert-nextjs-developer.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 | $0.00029 | $0.04341 |
| Opus 5.5 | $0.00012 | $0.01736 |
| Sonnet 5.5 | $0.00006 | $0.00868 |
| Haiku 4.5 | $0.00003 | $0.00434 |
Grade B, and why
expert-nextjs-developer scanned grade B with 1 finding 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 2mo 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.
Sends data to an external URLmediumData exfiltration
A POST to an outside endpoint may be telemetry or may be exfiltration; either way the mod talks to somewhere, and you should know where.
const res = await fetch("https://api.example.com/posts", { method: "POST", The source is not reproduced here
No licence file
A repository with no LICENSE is all rights reserved by default, so the body is not copied here. The metadata, the measurements and the link are.
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.
- 2mo ago First seen · 477 lines · 29 tokens per session scan B d0c42a0cc783
expert-nextjs-developer is an agent published in the GitHub repository bhf/st-k8s (1 stars, last pushed 6mo ago), with no licence file. It adds 29 tokens to every session and 4,341 once invoked, about $0.0001 per session on Opus 5.5. A static security scan graded it B with 1 finding (sends data to an external url). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.
expert-nextjs-developer compared with agents from other repositories
| Mod | Type | Stars | Last push | Licence | Scan | Tokens | Works with |
|---|---|---|---|---|---|---|---|
| expert-nextjs-developerbhf/st-k8s | Agent | 1 | 6mo ago | none | B | 29 | Claude Code |
| react-frontend-engineeralexmmatos/arthur-mcp | Agent | 2 | 3mo ago | MIT | A | 70 | Claude Code |
| Expert React Frontend Engineergithub/awesome-copilot | Agent | 41k | yesterday | MIT | B | 30 | Claude Code |
| Frontend Developermicrosoft/skills | Agent | 3.2k | yesterday | MIT | A | 24 | Claude Code |
| customchihebnabil/lovable-boilerplate | Agent | 66 | 2d ago | MIT | A | 38 | GitHub Copilot |
| react-frontend-development-expertgiuseppe-trisciuoglio/developer-kit | Agent | 367 | 1mo ago | MIT | A | 78 | Claude Code |
| frontend-engineerjpoley/flowspec | Agent | 50 | 28d ago | Apache-2.0 | A | 24 | Claude Code |