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 skills add melodic-software/claude-code-plugins --skill usegit clone --depth 1 https://github.com/melodic-software/claude-code-pluginsWrote 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/skills/melodic-software/claude-code-plugins/use)<a href="https://agentmods.dev/skills/melodic-software/claude-code-plugins/use"><img src="https://agentmods.dev/badge/skills/melodic-software/claude-code-plugins/use/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/skills/melodic-software/claude-code-plugins/use"><img src="https://agentmods.dev/badge/skills/melodic-software/claude-code-plugins/use.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector pass
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 | $0.00183 | $0.01642 |
| Opus 5.5 | $0.00073 | $0.00657 |
| Sonnet 5.5 | $0.00037 | $0.00328 |
| Haiku 4.5 | $0.00018 | $0.00164 |
Grade A, and why
use 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 26d 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.
How it starts
The opening of the file, as written. The whole thing — 134 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Use playgrounds
Purpose
Connect a playground-shaped request (an interactive parameter space the user wants to
manipulate visually, with the result flowing back as a prompt) to the maintained
first-party implementation: the playground skill from the playground plugin on the
claude-plugins-official marketplace. This skill routes, installs, and advises. It
never builds a playground itself.
Step 1: Presence check (provenance, not prose)
Determine whether the upstream plugin is installed by its identity, not its wording:
- Run
claude plugin listand look for theplaygroundplugin sourced fromclaude-plugins-official. That marketplace-qualified install record is the authoritative signal. - Where the CLI is unavailable to the session, fall back to the session's skill
listing: a bare
playgroundskill whose description says it creates interactive HTML playgrounds. Treat the description comparison as ADVISORY only; upstream may reword it at any time, and a listing under budget pressure can drop descriptions entirely. Never conclude "absent" from wording alone when the name is present. - A local skill can shadow the upstream name. When the listed
playgroundskill's description clearly describes something other than an interactive-explorer builder, say a shadow is likely, then let provenance decide: with the install record confirmingplayground@claude-plugins-official, warn about the shadow and invoke the namespacedplayground:playgroundform (a bare-name shadow cannot intercept it); with no install record confirming it, take the install/guidance path, and never invoke the shadowing skill.
Step 2: Present, so invoke
When the upstream skill is present, invoke it via the Skill tool with the user's
brief as arguments: the namespaced form playground:playground is the reliable
address for a plugin skill; the bare playground form resolves only while no other
skill carries that name. Pass the request
as stated; the upstream skill owns template choice and generation. When the user names
styles to leave out (a cream background, pill-shaped buttons), carry that list in the
brief; when they dislike a choice in the generated page, add it to the list and invoke
again. A general "make it look less generic" only swaps one default for another. If
the invocation is refused, do not retry blind: tell the user the skill is installed but this session
could not invoke it, and suggest they run it themselves by asking for a playground in
their own words.
What ships with it
2 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
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.
- 26d ago Changed · +3 lines 862023cd0519
- 1mo ago Changed 50e22c273e7e
- 1mo ago Changed · -8 tokens per session 16e62258aa85
- 1mo ago First seen · 131 lines · 191 tokens per session scan A 0d3395af5226
use is a skill published in the GitHub repository melodic-software/claude-code-plugins (26 stars, last pushed today), licensed MIT. It adds 183 tokens to every session and 1,642 once invoked, about $0.0007 per session on Opus 5.5. 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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