arithmetic-answers

arithmetic-answers is a skill for Claude Code, Codex from skillberry-ai/cap-evolve. It costs 36 tokens per session (109 once invoked), scanned A, original, Apache-2.0.

A focused helper for answering short arithmetic questions with only the final number.

In plain words
What is it for?
Computing sums, differences, and products, including expressions written with number words or thousands separators.
Why use it?
It avoids extra working, words, units, or punctuation when a user wants a bare calculation result.

Skill for Claude CodeCodex

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.

agentmods
npx agentmods add skills/skillberry-ai/cap-evolve/seed_capability
Any agent
npx skills add skillberry-ai/cap-evolve --skill seed_capability
Clone the repo
git clone --depth 1 https://github.com/skillberry-ai/cap-evolve

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 arithmetic-answers

README.md
[![agentmods](https://agentmods.dev/badge/skills/skillberry-ai/cap-evolve/seed_capability.svg)](https://agentmods.dev/skills/skillberry-ai/cap-evolve/seed_capability)
Your own site
<a href="https://agentmods.dev/skills/skillberry-ai/cap-evolve/seed_capability"><img src="https://agentmods.dev/badge/skills/skillberry-ai/cap-evolve/seed_capability.svg" alt="Measured on agentmods" height="20"></a>
Per session 36 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 109 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
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 $0.00036 $0.00109
Opus 5 $0.00018 $0.00055
Sonnet 5 $0.00007 $0.00022
Haiku 4.5 $0.00004 $0.00011

Measured 4d ago against content hash f58a437ae7f5, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

arithmetic-answers 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 4d 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.

examples/toy_skill/seed_capability/SKILL.md · 14 lines

What it actually says

Arithmetic answers

Read the expression, compute it, and reply with the number alone — no units, no working, no trailing punctuation.

Inputs are not always tidy: people write number words ("plus", "minus", "times") and thousands separators ("1,200"). Normalize the expression to plain digits and operators before computing.

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. 4d ago First seen · 14 lines · 36 tokens per session scan A f58a437ae7f5

Subscribe to this mod's changes

arithmetic-answers is a skill published in the GitHub repository skillberry-ai/cap-evolve (50 stars, last pushed today), licensed Apache-2.0. It adds 36 tokens to every session and 109 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.