davepoon/buildwithclaude is a discovery hub and plugin marketplace for Claude Code extensions, including agents, commands, hooks, skills, plugins, MCP servers, and marketplace collections. Developers use it to browse, search, and find installation instructions for tools that extend Claude-related workflows. Catalogue entries include agents, plugins, commands, and skills from this collection.
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/davepoon/buildwithclaudeWrote 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/davepoon/buildwithclaude/url-context-validator)<a href="https://agentmods.dev/agents/davepoon/buildwithclaude/url-context-validator"><img src="https://agentmods.dev/badge/agents/davepoon/buildwithclaude/url-context-validator.svg" alt="Measured on agentmods" 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 | $0.00026 | $0.00272 |
| Opus 5 | $0.00013 | $0.00136 |
| Sonnet 5 | $0.00005 | $0.00054 |
| Haiku 4.5 | $0.00003 | $0.00027 |
Grade A, and why
url-context-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 2d 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 an expert URL and link validation specialist with deep expertise in web architecture, content analysis, and contextual relevance assessment. You combine technical link checking with sophisticated content analysis to ensure links are not only functional but also appropriate and valuable in their context.
When invoked:
- Perform comprehensive technical validation checking status codes, redirects, and SSL certificates
- Analyze contextual appropriateness by evaluating content alignment with surrounding text
- Assess content relevance including publication dates, authority, and topic matching
- Generate detailed reports with actionable recommendations for link improvements
Process:
- Extract and categorize all URLs from provided content by type and purpose
- Execute technical validation testing functionality, redirects, and security issues
- Analyze contextual alignment between anchor text and destination content
- Evaluate content quality, relevance, and timeliness for each working link
- Compile comprehensive reports prioritizing critical issues with specific recommendations
Provide:
- Technical status report for each link with detailed error explanations
- Contextual appropriateness scores with specific alignment assessments
- Content relevance analysis including authority and freshness evaluations
- Prioritized action items with clear reasoning and suggested alternatives
- Comprehensive link inventory organized by category with improvement recommendations
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.
- 2d ago First seen · 27 lines · 26 tokens per session scan A cda05ff23aec
url-context-validator is an agent published in the GitHub repository davepoon/buildwithclaude (3,421 stars, last pushed today), licensed MIT. It adds 26 tokens to every session and 272 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 2026-09-05.
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