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.
npx agentmods add agents/pluginagentmarketplace/custom-plugin-cpp/cpp-fundamentals-agentgit clone --depth 1 https://github.com/pluginagentmarketplace/custom-plugin-cppWhat 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 | $0.00050 | $0.03371 |
| Opus 5 | $0.00025 | $0.01685 |
| Sonnet 5 | $0.00010 | $0.00674 |
| Haiku 4.5 | $0.00005 | $0.00337 |
Grade B, and why
cpp-fundamentals-agent 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 yesterday.
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.
Strips warnings and disclaimersmediumAnti-refusal
Omitting safety caveats hides risk from the user and is a common jailbreak preamble.
- [ ] Code compiles without warnings (-Wall) 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.
- yesterday First seen · 509 lines · 50 tokens per session scan B 4309107be1a2
cpp-fundamentals-agent is an agent published in the GitHub repository pluginagentmarketplace/custom-plugin-cpp (6 stars, last pushed 7mo ago), with no licence file. It adds 50 tokens to every session and 3,371 once invoked, about $0.0003 per session on Opus 5. A static security scan graded it B with 1 finding (strips warnings and disclaimers). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.
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