fiftyone-eval-plugin

fiftyone-eval-plugin is a skill for Claude Code from voxel51/fiftyone-skills. It costs 60 tokens per session (4,142 once invoked), scanned B, original, Apache-2.0.

A review skill for checking FiftyOne plugins for code quality, security, and compatibility with the FiftyOne plugin system.

In plain words
What is it for?
It is for reading plugin files, checking their behavior against FiftyOne's system, and producing findings with locations and suggested fixes.
Why use it?
It helps identify unsafe code, incorrect plugin registration, and specific problems before a plugin is installed or used.

Skill for Claude Code

Written for Claude Code: shipped in a Claude Code plugin.

Part of the fiftyone-skills plugin — 18 skills, 2 commands, 1 MCP server shipped together

Good fit It is for reading plugin files, checking their behavior against FiftyOne's system, and producing findings with locations and suggested fixes.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/voxel51/fiftyone-skills/fiftyone-eval-plugin
Install

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.

Any agent
npx skills add voxel51/fiftyone-skills --skill fiftyone-eval-plugin
Clone the repo
git clone --depth 1 https://github.com/voxel51/fiftyone-skills

Made for: Claude Code.

Or install fiftyone-skills, the plugin that ships this one along with the rest of its 18 skills, 2 commands, 1 MCP server.

Wrote 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.

agentmods badge for fiftyone-eval-plugin

README.md
[![agentmods](https://agentmods.dev/badge/skills/voxel51/fiftyone-skills/fiftyone-eval-plugin/github.svg)](https://agentmods.dev/skills/voxel51/fiftyone-skills/fiftyone-eval-plugin)
Your own site
<a href="https://agentmods.dev/skills/voxel51/fiftyone-skills/fiftyone-eval-plugin"><img src="https://agentmods.dev/badge/skills/voxel51/fiftyone-skills/fiftyone-eval-plugin/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.

agentmods 80×15 button for fiftyone-eval-plugin

Your own site · 80×15
<a href="https://agentmods.dev/skills/voxel51/fiftyone-skills/fiftyone-eval-plugin"><img src="https://agentmods.dev/badge/skills/voxel51/fiftyone-skills/fiftyone-eval-plugin.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 60 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 4,142 The whole file, excluding the scripts and references it only reads on demand.
Security scan B 3 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin original No closer match found in the catalogue.
Token cost

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.

ModelPer sessionOnce invoked
Fable 5.1 $0.00060 $0.04142
Opus 5 $0.00030 $0.02071
Sonnet 5 $0.00012 $0.00828
Haiku 4.5 $0.00006 $0.00414

Measured 10d ago against content hash c4bb90d5e9e0, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-10, from the pricing page.

Security

Grade B, and why

fiftyone-eval-plugin scanned grade B with 3 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 10d 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.

Harvests environment variablesmediumData exfiltration

Enumerating or grepping the environment for keys collects credentials unrelated to what the mod says it does.

**Critical:** Iterating over `os.environ` to dump all environment variables or sending environment variable contents to locations not related to service authentication.

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.

urllib # Same

Runs shell commandslowCapability

Expected in a hook, worth knowing in a rule or an instructions file.

os.system # Same
skills/fiftyone-eval-plugin/SKILL.md · 364 lines

How it starts

The opening of the file, as written. The whole thing — 364 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Evaluate FiftyOne Plugins

Key Directives

ALWAYS follow these rules:

1. Read the entire plugin before judging

Read every source and configuration file of the plugin. Common file extensions: .py, .ts, .tsx, .js, .yaml, .yml, and .json. Never construct an assessment of a plugin without first reading every line of every source file.

2. Security first

Check for dangerous patterns before anything else. A plugin with perfect code quality that violates established and well known security best practices, is an immediate critical failure.

3. Be specific and actionable

Every finding must include: what's wrong, where it is (file + line), why it matters, and how to fix it. Never say "improve code quality" without pointing to the exact issue.

4. Score honestly

A plugin by a trusted org with security issues still gets a security failure. A community plugin with great code still gets credit. Judge the code, not the author.

5. Check the real plugin framework

Always verify the plugin under assessment against the actual FiftyOne plugin system. Use MCP tools to list operators, get schemas, and check registration — don't just read files.

list_plugins(enabled=True)
list_operators(builtin_only=False)
get_operator_schema(operator_uri="@org/operator-name")

Evaluation Workflow

Phase 1: Manifest & Structure

Check the plugin is well-formed before loading it.

1.1 Parse fiftyone.yml:

  • name exists and follows convention (@org/plugin-name)
  • version is present and valid semver
  • fiftyone.version constraint is specified
  • operators and/or panels lists are non-empty
  • secrets are declared if the plugin uses API keys

1.2 Skills declaration:

  • Check if fiftyone.yml includes a skills: section listing companion skills (similar to operators: and panels:)
  • If skills: is declared, verify each listed skill has a matching SKILL.md file in the plugin directory following the Agent Skills format (YAML frontmatter with name and description, plus workflow sections)
  • If no skills: section exists, note this as an observation — the plugin does not ship with companion skills for AI assistants. This is not a penalty, but plugins with skills have higher agent success rates.

Read the full file on GitHub · 364 lines

Files

What ships with it

1 file 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.

Changes

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.

  1. 10d ago First seen · 364 lines · 60 tokens per session scan B c4bb90d5e9e0

Subscribe to this mod's changes

fiftyone-eval-plugin is a skill published in the GitHub repository voxel51/fiftyone-skills (39 stars, last pushed 24d ago), licensed Apache-2.0. It adds 60 tokens to every session and 4,142 once invoked, about $0.0003 per session on Opus 5. A static security scan graded it B with 3 findings (harvests environment variables, makes network calls, runs shell commands). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

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