hafogvatn

hafogvatn is a skill for Claude Code, Codex from jokull/icelandic-data. It costs 33 tokens per session (243 once invoked), scanned A, original, MIT.

A data tool for publications from Iceland’s Marine and Freshwater Research Institute (MFRI), which assesses fish stocks and advises on sustainable catches.

In plain words
What is it for?
Use it to list available stock assessments and fetch annual cod data, including advice, catch limits, landings, age data, and survey series.
Why use it?
It provides a repeatable way to retrieve annual assessment tables instead of copying them from web pages. It also keeps the publication year visible because older estimates may be revised.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one. Also seen: installed under .agents/ (shared by several agents).

Needs its repository: it runs a file that does not travel with it, so clone the repository first. The line is uv run python scripts/hafogvatn.py list.

Good fit Use it to list available stock assessments and fetch annual cod data, including advice, catch limits, landings, age data, and survey series.

Compare 6 skills from other repositories ↓
Install

Getting it into your agent

It runs from inside its repository, so the clone comes first — what it calls does not travel with the file alone.

Clone the repo
git clone --depth 1 https://github.com/jokull/icelandic-data
agentmods
npx agentmods add skills/jokull/icelandic-data/hafogvatn

Made for: Claude Code, Codex.

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 hafogvatn

README.md
[![agentmods](https://agentmods.dev/badge/skills/jokull/icelandic-data/hafogvatn/github.svg)](https://agentmods.dev/skills/jokull/icelandic-data/hafogvatn)
Your own site
<a href="https://agentmods.dev/skills/jokull/icelandic-data/hafogvatn"><img src="https://agentmods.dev/badge/skills/jokull/icelandic-data/hafogvatn/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 hafogvatn

Your own site · 80×15
<a href="https://agentmods.dev/skills/jokull/icelandic-data/hafogvatn"><img src="https://agentmods.dev/badge/skills/jokull/icelandic-data/hafogvatn.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 33 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 243 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe. Third-party audits
  • NVIDIA SkillSpector pass 7 Sept 2026
How audits are shown
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 $0.00033 $0.00243
Opus 5 $0.00016 $0.00121
Sonnet 5 $0.00007 $0.00049
Haiku 4.5 $0.00003 $0.00024

Measured 9d ago against content hash c4b4071e3583, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-09, from the pricing page.

Security

Grade A, and why

hafogvatn 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 9d 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.

.agents/skills/hafogvatn/SKILL.md · 32 lines

What it actually says

Hafrannsóknastofnun — Marine and Freshwater Research Institute

MFRI publishes annual stock advice with current assessment tables embedded as JSON inside static HTML pages.

Data

Catalogue: https://www.hafogvatn.is/en/moya/extras/categories/radgjof

The current cod table has assessment summaries, landings, advice/TAC history, catch-at-age and survey series. Its stable pattern is /static/extras/images/1_cod_{year}_1_tables_en.html.

Usage

uv run python scripts/hafogvatn.py list
uv run python scripts/hafogvatn.py fetch --stock cod --year 2026

Caveats

  1. Assessment vintages revise historic estimates: retain publication year.
  2. The per-stock table schemas and assessment methods differ.
  3. The old data.hafro.is CSV archive is useful historically but is not the current annual publication channel.
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. 9d ago First seen · 32 lines · 33 tokens per session scan A c4b4071e3583

Subscribe to this mod's changes

hafogvatn is a skill published in the GitHub repository jokull/icelandic-data (52 stars, last pushed yesterday), licensed MIT. It adds 33 tokens to every session and 243 once invoked, about $0.0002 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 2026-08-30.

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