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 eunji-jessi-jung/reef/plugin install reefWrote 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/eunji-jessi-jung/reef/artifact)<a href="https://agentmods.dev/skills/eunji-jessi-jung/reef/artifact"><img src="https://agentmods.dev/badge/skills/eunji-jessi-jung/reef/artifact/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/eunji-jessi-jung/reef/artifact"><img src="https://agentmods.dev/badge/skills/eunji-jessi-jung/reef/artifact.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 | $0.00011 | $0.02362 |
| Opus 5 | $0.00005 | $0.01181 |
| Sonnet 5 | $0.00002 | $0.00472 |
| Haiku 4.5 | $0.00001 | $0.00236 |
Grade A, and why
artifact 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 12d 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 — 292 lines — stays where its author put it; the contents beside it link to each section on GitHub.
/reef:artifact
Work with reef artifacts conversationally. The user never needs to know artifact types or IDs — reef figures out where knowledge belongs.
Setup
Read these references before doing anything else:
${CLAUDE_PLUGIN_ROOT}/references/artifact-contract.md${CLAUDE_PLUGIN_ROOT}/references/methodology.md
Voice
Curious Researcher. Present-participle narration. No emojis. No exclamation marks.
Procedure
1. Locate the reef
Walk up from cwd looking for a .reef/ directory. That parent is the reef root. If not found, stop and tell the user to run /reef:init first.
Read .reef/project.json for service list and source paths.
2. Determine mode
Parse the user's request to determine which mode to use. The user will NOT say "explore mode" or "capture mode" — they will speak naturally. Match their intent:
Explore mode — the user has a topic or question they want to investigate:
- "I want to dig deeper into how order finalization works"
- "What do we know about the notification system?"
- "Is there anything about how Orders and Payments share transaction data?"
- "I want to create something about the caching layer"
Capture mode — the user learned something and wants to persist it:
- "Oh, I didn't know that — can we add that to the reef?"
- "We should document that the queue uses RabbitMQ, not Redis"
- "Can we save what we just discussed about auth token rotation?"
Update mode — the user names a specific artifact to modify:
- "Update SCH-ORDERS-CORE"
- "Add a Key Fact to PROC-ORDERS-FULFILLMENT about the new validation"
- "The freshness note on SYS-PAYMENTS is wrong"
If the intent is ambiguous, ask one clarifying question. Do not ask the user to pick a mode — just ask about their topic.
3. Explore mode
The user arrives with a topic, question, or area of interest. Reef's job: find what exists, read the source code, and either enrich an existing artifact or create a new one.
3a. Search the reef
Search for existing coverage of the user's topic:
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.
- 12d ago First seen · 292 lines · 11 tokens per session scan A 43750336522b
artifact is a skill published in the GitHub repository eunji-jessi-jung/reef (5 stars, last pushed 4mo ago), licensed Apache-2.0. It adds 11 tokens to every session and 2,362 once invoked, about $0.0001 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 2026-08-31.
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