Getting it into your agent
This one installs as part of its plugin. Adding the marketplace and installing the plugin brings it with everything else the plugin ships.
/plugin marketplace add Emasoft/claude-plugins-validation/plugin install claude-plugins-validationWrote 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/emasoft/claude-plugins-validation/cpv-cache-validation-skill)<a href="https://agentmods.dev/skills/emasoft/claude-plugins-validation/cpv-cache-validation-skill"><img src="https://agentmods.dev/badge/skills/emasoft/claude-plugins-validation/cpv-cache-validation-skill/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/emasoft/claude-plugins-validation/cpv-cache-validation-skill"><img src="https://agentmods.dev/badge/skills/emasoft/claude-plugins-validation/cpv-cache-validation-skill.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 | $0.00065 | $0.01413 |
| Opus 5.5 | $0.00026 | $0.00565 |
| Sonnet 5.5 | $0.00013 | $0.00283 |
| Haiku 4.5 | $0.00006 | $0.00141 |
Grade B, and why
cpv-cache-validation-skill scanned grade B with 2 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 1mo 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.
Downloads and executes remote codemediumSupply chain
curl | sh runs whatever the server returns today, which is not necessarily what it returned when this was reviewed.
runs. Install via `curl -LsSf https://astral.sh/uv/install.sh | sh`. Downgraded: this mod is about security review, or the phrase is quoted, so it is likely naming the pattern rather than instructing it.
Makes network callslowCapability
Not a fault in itself. Listed so you know the mod talks to something, and to what.
runs. Install via `curl -LsSf https://astral.sh/uv/install.sh | sh`. How it starts
The opening of the file, as written. The whole thing — 100 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Cache-Audit Skill (loaded by cpv-cache-optimizer-agent)
Overview
Anthropic's prompt cache caches the rendered system-prompt prefix —
CLAUDE.md, cached agent/skill bodies, and settings-derived blocks. The
cache is invalidated whenever ANY byte in that prefix changes. A 200K-token
prefix cache MISS costs ~10x normal token rate vs a HIT. CPV's cache-audit
rule pack catches the seven documented patterns that silently break caching
or fork the cached prompt into many distinct keys.
Severity: every CA-01..CA-07 finding is a WARNING (non-blocking — a
cache miss costs tokens/latency but never makes a plugin invalid).
validate_plugin CALLS this scanner as a SEPARATE step (its own report + a
one-line pointer in the main report); this skill + cpv-cache-optimize act
on the findings. CA-04 covers a model: frontmatter on ANY component
(agents, commands, skills); model: inherit is exempt.
Per-rule severity, catch description, and fix-recipe pointer live in references/ca-rules.md. Full TOC of every rule is embedded under "Resources" at the bottom of this file.
Prerequisites
- A Claude Code plugin directory OR a project root that uses Claude Code.
uvavailable on PATH so the validator can run via the launcher (uv run --with pyyaml python "${CLAUDE_PLUGIN_ROOT}/scripts/remote_validation.py" cache <path>).
Scanner contract
Same I/O contract as validate_security.py: path-only stdout (auto-save
report, print compact summary), aggregated (level, rule_id) grouping,
self-scan filter chain (skips catalog / test / dev-scratch files).
Instructions
- Read references/launcher-invocation.md for the canonical bash one-liner (alias
cache).The one-liner · Why the launcher is mandatory · Direct invocation (development only)
- Resolve
MAIN_ROOTviagit worktree list | head -n1. - Run the launcher with
--report "$MAIN_ROOT/reports/validate_cache/<TS>-<slug>.md". - Read the compact summary from stdout, full details from the report file.
- (Fix workflow only — cpv-cache-optimizer-agent.) Group findings by CA-NN, apply
cache-fixes.md#ca-nnfromskills/cpv-fix-validation/references/, re-run, iterate until ZERO CA findings remain. Every CA finding is a WARNING, so the verdict is VALID from the start — terminate on an empty findings set, not on VALID.
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.
- 1mo ago First seen · 100 lines · 65 tokens per session scan B 87192047b69f
cpv-cache-validation-skill is a skill published in the GitHub repository Emasoft/claude-plugins-validation (4 stars, last pushed 3d ago), licensed MIT. It adds 65 tokens to every session and 1,413 once invoked, about $0.0003 per session on Opus 5.5. A static security scan graded it B with 2 findings (downloads and executes remote code, makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.
Other skills, from other repositories
research-engineer
An uncompromising Academic Research Engineer. Operates with absolute scientific rigor, objective criticism, and zero flair. Focuses on theoretical correctness, formal verification, and optimal implementation across any required technology.
eval-dataset-design
A guide to creating reliable test sets for AI agents. Each evaluation task includes the request, the simulated user's behaviour, a reset starting state, and a success check that can be independently verified.
tika-eval-compare
Compare extracts from two Tika builds over a corpus to detect regressions in content, encoding, exceptions, and embedded-document handling. Use for "compare before/after extracts", "eval this change against the corpus".
cua-driver
Use Cua Driver for desktop or browser tasks that are awkward or unavailable through Bash/APIs, or when the user explicitly wants GUI interaction: app testing, visual bug reproduction, form filling, calendar entry, screenshots, and demo recording. Also covers Cua setup; not OpenAI Codex Computer Use or web research.
jetson-validate-image
Use after jetson-flash-image to run static BSP checks, on-target smoke/regression tests on a flashed DUT, or both. Not for build or flash steps. Triggers: validate bsp, on-target validation.
atmos-validation
Validate Atmos projects, components, arbitrary JSON Schema inputs, EditorConfig, and GitHub Actions; use affected-file selection and native CI annotations.