kendex: Skill for Claude Code

.agents/skills/decider/SKILL.md

decider is a skill for Claude Code from vanillagreencom/kendex. It costs 17 tokens per session (977 once invoked), scanned C, original, MIT.

A system for recording important architecture choices in numbered decision documents, with an index and search commands. An architecture decision record explains a significant technical choice and why it was made.

In plain words
What is it for?
Use it to search, list, read, create, or replace architecture decision records, subject to the required approval for creating them.
Why use it?
It helps agents find existing design decisions before proposing changes and prevents new work from quietly contradicting agreed choices.

Skill for Claude Code

Written for Claude Code: user-invocable in frontmatter. Also seen: installed under .agents/ (shared by several agents); mentions AGENTS.md.

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

Reuse

Borrowing it

Nothing to install: this file belongs to vanillagreencom/kendex. 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/vanillagreencom/kendex/main/.agents/skills/decider/SKILL.md
Clone the repo
git clone --depth 1 https://github.com/vanillagreencom/kendex

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 decider

README.md
[![agentmods](https://agentmods.dev/badge/skills/vanillagreencom/kendex/decider/github.svg)](https://agentmods.dev/skills/vanillagreencom/kendex/decider)
Your own site
<a href="https://agentmods.dev/skills/vanillagreencom/kendex/decider"><img src="https://agentmods.dev/badge/skills/vanillagreencom/kendex/decider/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 decider

Your own site · 80×15
<a href="https://agentmods.dev/skills/vanillagreencom/kendex/decider"><img src="https://agentmods.dev/badge/skills/vanillagreencom/kendex/decider.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 17 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 977 The whole file, excluding the scripts and references it only reads on demand.
Security scan C 1 finding. A grade says what 26 rules found in the file — not that it is safe.
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 $0.00017 $0.00977
Opus 5.5 $0.00007 $0.00391
Sonnet 5.5 $0.00003 $0.00195
Haiku 4.5 $0.00002 $0.00098

Measured 21d ago against content hash 673685772b06, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade C, and why

decider scanned grade C with 1 finding 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 21d ago.

The scan reads SKILL.md. This mod also ships 1 executable file (scripts/lib/kendex-env.sh), 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.

Hidden instructionshighPrompt injection

Directives inside HTML comments, invisible characters or bidirectional overrides are read by the model and not by the person reviewing the file.

<!-- kendex:project-instructions:start -->
.agents/skills/decider/SKILL.md · 66 lines

How it starts

The opening of the file, as written. The whole thing — 66 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Project Instructions

Problems with a kendex-owned skill go through kendex report; check ownership in the file first.

Decider

Numbered decision documents indexed in one INDEX.md (default docs/decisions/), with a search CLI, canonical format, and creation/supersession workflows.

.agents/skills/decider/scripts/decisions <command> [options]

Actions (search, search --issue, list, next-id, get, check), search coverage and scoring, output shapes, and the DECISIONS_DIR / DECISIONS_BASE_REF / DECISION_ID_* environment: decisions --help. There is no bare issue action; use search --issue.

Read a hit's INDEX row first. Read an active or superseded record's document before treating it as binding. When considering a withdrawn option, read its retained document and withdrawal reason. A removed record's reason lives where its Rationale cell names it, the comment at the code or the principle doc's section. An active decision binds design policy; a suggestion contradicting it is invalid unless the decision itself is flawed. One marked superseded binds only what its status leaves active; a withdrawn one binds nothing; a removed one binds through the code or principle doc its INDEX row names.

What warrants a decision record, and why

A record exists to stop a reversal: a reviewer or a future agent, reading the code alone, would undo the choice because the code cannot show its reason. Judge the reach and the reason, not the number of sites.

Warranted:

  • A choice that governs work beyond one site: one merge path for every repository; every removal goes to the trash and nothing deletes.
  • A choice a reviewer or a future agent would otherwise reverse: a hand-written WebSocket client kept over a dependency, in a catalog that ships standard-library scripts.
  • A choice whose reason the code cannot show: a bound set below a measured incident, with the measurement as its reason.

Read the full file on GitHub · 66 lines

Files

What ships with it

9 files 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. 21d ago Changed · -1 lines 673685772b06
  2. 22d ago Changed c49cd5219b08
  3. 23d ago Changed · +17 lines 47f8b69cf4b0
  4. 1mo ago Changed 45d1562de179
  5. 1mo ago Changed · +6 lines scan A → C dceafd0ea65a
  6. 2mo ago First seen · 44 lines · 17 tokens per session scan A ff0bd51d087a

Subscribe to this mod's changes

decider is a skill published in the GitHub repository vanillagreencom/kendex (87 stars, last pushed yesterday), licensed MIT. It adds 17 tokens to every session and 977 once invoked, about $0.0001 per session on Opus 5.5. A static security scan graded it C with 1 finding (hidden instructions). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.