yantrikdb: Skill for Claude Code

.claude/skills/build-pack/SKILL.md

build-pack is a skill for Claude Code from yantrikos/yantrikdb. It costs 88 tokens per session (2,321 once invoked), scanned A, original, Apache-2.0.

A tool for creating and measuring YantrikDB knowledge packs. YantrikDB packs are sealed files that a local AI model can mount to add specific knowledge or working methods.

In plain words
What is it for?
Use it to turn documentation or a subject area into a pack, measure its results across model sizes, and publish it to packs.yantrikdb.com.
Why use it?
It helps determine whether a pack actually improves a model on checks defined before testing, instead of judging it by the appearance of its documentation.

Skill for Claude Code

Written for Claude Code: installed under .claude/.

This is yantrikos/yantrikdb's own configuration. It tells Claude Code how to work on yantrikdb 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 yantrikdb configures →

Needs its repository: it runs a file that does not travel with it, so clone the repository first. The line is python packs/lint_pack.py <pack> # rules without evidence, records nobody can reach.

Reuse

Borrowing it

Nothing to install: this file belongs to yantrikos/yantrikdb. 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/yantrikos/yantrikdb/main/.claude/skills/build-pack/SKILL.md
Clone the repo
git clone --depth 1 https://github.com/yantrikos/yantrikdb

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 build-pack

README.md
[![agentmods](https://agentmods.dev/badge/skills/yantrikos/yantrikdb/build-pack/github.svg)](https://agentmods.dev/skills/yantrikos/yantrikdb/build-pack)
Your own site
<a href="https://agentmods.dev/skills/yantrikos/yantrikdb/build-pack"><img src="https://agentmods.dev/badge/skills/yantrikos/yantrikdb/build-pack/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 build-pack

Your own site · 80×15
<a href="https://agentmods.dev/skills/yantrikos/yantrikdb/build-pack"><img src="https://agentmods.dev/badge/skills/yantrikos/yantrikdb/build-pack.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 88 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,321 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 $0.00088 $0.02321
Opus 5 $0.00044 $0.01161
Sonnet 5 $0.00018 $0.00464
Haiku 4.5 $0.00009 $0.00232

Measured 10d ago against content hash 3204f3c74c04, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-10, from the pricing page.

Security

Grade A, and why

build-pack 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 10d 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/build-pack/SKILL.md · 209 lines

How it starts

The opening of the file, as written. The whole thing — 209 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Building a pack

A pack is a sealed, signed YantrikDB file a model mounts to gain knowledge and behaviour it lacks, and unmounts without a trace. This skill covers authoring one that is worth shipping — which is decided by measurement, not by how good the corpus looks.

The one thing to get right first

A pack shifts knowledge and procedure. It does not raise raw capability. Every claim must be phrased so it can be checked:

  • ✗ "makes your model write like Shakespeare"
  • ✓ "raises compliance with Shakespearean craft rules from 7/12 to 10/12 on qwen3.5:4b, on checks written down before the run"

If you cannot state the claim as a measured delta on named checks, you do not yet know whether the pack works.

Which of the four shapes is this?

Measured across three model sizes; the shape predicts the payoff and the buyer.

Shape Example Typical lift Who buys it
Knowledge the model cannot have private codebase, post-cutoff API huge (1/20 → 18/20) anyone running a local model
Method it knows but doesn't apply reasoning discipline, review procedure large at every size (+5 to +8) everyone — the most underserved shape
Framework house rules React, WordPress conventions moderate; ceiling is high already small-model operators
Style craft rules period voice, brand tone real but smallest small-model operators

Two findings worth carrying: method packs lift even a 27B, because models know what a procedure is and reach for it only when it is in front of them. Craft and domain packs are inverse to model size — a 27B often scores near ceiling unaided, so say who the pack is for instead of promising uniform lift.

The three tiers

pack/
  pack.toml         identity, namespace, ingest defaults, coverage
  corpus.md         the knowledge — retrieved on similarity
  constitution.md   the rules — injected on EVERY turn (optional)
  eval.jsonl        questions with deterministic expectations

Read the full file on GitHub · 209 lines

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. 10d ago First seen · 209 lines · 88 tokens per session scan A 3204f3c74c04

Subscribe to this mod's changes

build-pack is a skill published in the GitHub repository yantrikos/yantrikdb (58 stars, last pushed today), licensed Apache-2.0. It adds 88 tokens to every session and 2,321 once invoked, about $0.0004 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.