mathilda: Skill for Claude Code

.claude/skills/llm-feature/SKILL.md

llm-feature is a skill for Claude Code from stblake/mathilda. It costs 51 tokens per session (1,843 once invoked), scanned A, original, GPL-3.0.

A set of guidance for building features that use AI or large language models, such as Claude or GPT.

In plain words
What is it for?
Use it when adding or improving an AI feature in an application.
Why use it?
It helps structure work involving model APIs, prompts, machine-readable results, tool calls, streaming responses, and output evaluation.

Skill for Claude Code

Written for Claude Code: allowed-tools in frontmatter.

This is stblake/mathilda's own configuration. It tells Claude Code how to work on mathilda itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything mathilda configures →

Reuse

Borrowing it

Nothing to install: this file belongs to stblake/mathilda. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file
curl -O https://raw.githubusercontent.com/stblake/mathilda/main/.claude/skills/llm-feature/SKILL.md
Clone the repo
git clone --depth 1 https://github.com/stblake/mathilda

Made for: Claude Code.

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 llm-feature

README.md
[![agentmods](https://agentmods.dev/badge/skills/stblake/mathilda/llm-feature/github.svg)](https://agentmods.dev/skills/stblake/mathilda/llm-feature)
Your own site
<a href="https://agentmods.dev/skills/stblake/mathilda/llm-feature"><img src="https://agentmods.dev/badge/skills/stblake/mathilda/llm-feature/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 llm-feature

Your own site · 80×15
<a href="https://agentmods.dev/skills/stblake/mathilda/llm-feature"><img src="https://agentmods.dev/badge/skills/stblake/mathilda/llm-feature.svg" alt="Reviewed on agentmods" width="80" 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 1,843 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 $0.01843
Opus 5.5 $0.00020 $0.00737
Sonnet 5.5 $0.00010 $0.00369
Haiku 4.5 $0.00005 $0.00184

Measured 1mo ago against content hash 14ca3de4c40c, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

llm-feature 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 1mo 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.

.claude/skills/llm-feature/SKILL.md · 214 lines

The source is not reproduced here

Licensed GPL-3.0

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

Read it on GitHub

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. 1mo ago First seen · 214 lines · 51 tokens per session scan A 14ca3de4c40c

Subscribe to this mod's changes

llm-feature is a skill published in the GitHub repository stblake/mathilda (20 stars, last pushed today), licensed GPL-3.0. It adds 51 tokens to every session and 1,843 once invoked, about $0.0002 per session on Opus 5.5. 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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