aha

aha is a skill for Claude Code from OleksandrHavuka/shadowling. It costs 51 tokens per session (899 once invoked), scanned A, original, AGPL-3.0.

A language-learning command for explaining expressions that cannot be understood word for word. It gives a judgment about whether to memorize the expression or learn it as a reusable rule, then records the explanation.

In plain words
What is it for?
Use it when an expression is hard to interpret literally, optionally including your own guess about its meaning.
Why use it?
It helps resolve confusing phrases without treating every unfamiliar expression as an isolated item to memorize.

Skill for Claude Code

Written for Claude Code: allowed-tools in frontmatter.

Part of the shadowling plugin — 8 skills, 2 hooks shipped together

Good fit Use it when an expression is hard to interpret literally, optionally including your own guess about its meaning.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/oleksandrhavuka/shadowling/aha
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 OleksandrHavuka/shadowling --skill aha
Clone the repo
git clone --depth 1 https://github.com/OleksandrHavuka/shadowling

Made for: Claude Code.

Or install shadowling, the plugin that ships this one along with the rest of its 8 skills, 2 hooks.

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 aha

README.md
[![agentmods](https://agentmods.dev/badge/skills/oleksandrhavuka/shadowling/aha.svg)](https://agentmods.dev/skills/oleksandrhavuka/shadowling/aha)
Your own site
<a href="https://agentmods.dev/skills/oleksandrhavuka/shadowling/aha"><img src="https://agentmods.dev/badge/skills/oleksandrhavuka/shadowling/aha.svg" alt="Measured on agentmods" height="20"></a>
Per session 51 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 899 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.
Origin unknown 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 $0.00051 $0.00899
Opus 5 $0.00026 $0.00449
Sonnet 5 $0.00010 $0.00180
Haiku 4.5 $0.00005 $0.00090

Measured 8d ago against content hash a8e5b44c3333, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-08, from the pricing page.

Security

Grade A, and why

aha 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 8d ago.

The scan reads SKILL.md. This mod also ships 1 executable file (decode.py), listed below but not scanned — reading those needs a real analyzer, not pattern matching.

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.

plugins/shadowling/skills/aha/SKILL.md · 60 lines

The source is not reproduced here

Licensed AGPL-3.0

The repository is licensed AGPL-3.0, which this catalogue does not treat as permission to reproduce the file. Read it at the source.

Read it on GitHub

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. 8d ago First seen · 60 lines · 51 tokens per session scan A a8e5b44c3333

Subscribe to this mod's changes

aha is a skill published in the GitHub repository OleksandrHavuka/shadowling (2 stars, last pushed 2mo ago), licensed AGPL-3.0. It adds 51 tokens to every session and 899 once invoked, about $0.0003 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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