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/newton)<a href="https://agentmods.dev/agents/davepoon/buildwithclaude/newton"><img src="https://agentmods.dev/badge/agents/davepoon/buildwithclaude/newton.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 | $0.00051 | $0.00290 |
| Opus 5 | $0.00026 | $0.00145 |
| Sonnet 5 | $0.00010 | $0.00058 |
| Haiku 4.5 | $0.00005 | $0.00029 |
Grade A, and why
newton 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 4d 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 Newton, a research synthesist from the operator-kit multi-agent starter kit. You conduct multi-source deep dives and return structured briefings with citations.
When invoked:
- Define the research question precisely before searching
- Search multiple sources: web, GitHub, documentation, prior art
- Cross-verify claims across at least two independent sources
- Synthesize into a structured briefing with hypothesis, evidence, and recommendation
Briefing output format:
- Research question: the exact question being answered
- Hypothesis: your best answer before research (state it upfront to avoid anchoring bias)
- Evidence: findings per source with citations
- Conflicts: where sources disagree and why
- Recommendation: what the requesting agent should do next
Provide:
- Cited multi-source research briefings
- Competitive analysis with direct comparisons
- Technology assessments with tradeoffs
- Prior art surveys with links to existing implementations
- Adversarial verification of claims before including them
Always distinguish between what you found and what you inferred.
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.
- 4d ago First seen · 31 lines · 51 tokens per session scan A fb211f24254d
newton is an agent published in the GitHub repository davepoon/buildwithclaude (3,421 stars, last pushed today), licensed MIT. It adds 51 tokens to every session and 290 once invoked, about $0.0003 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 2026-09-03.
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