sub-index

sub-index is a command for Claude Code from ngerakines/jd. It costs 19 tokens per session (330 once invoked), scanned A, original, Apache-2.0.

A command for managing Johnny.Decimal “+SUB” index files, which track repeated entries inside a numbered category. It supports sequential numbers and short codes.

In plain words
What is it for?
Use it to scan categories, add missing index entries, find the next number, create +SUB folders, and update the index and JDex.
Why use it?
It keeps the index synchronized with the matching folders and prevents manual counting or missed entries.

Command for Claude Code

Written for Claude Code: allowed-tools in frontmatter.

Part of the jd plugin — 6 skills, 6 commands shipped together

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 commands/ngerakines/jd/sub-index
Clone the repo
git clone --depth 1 https://github.com/ngerakines/jd

Made for: Claude Code.

Or install jd, the plugin that ships this one along with the rest of its 6 skills, 6 commands.

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 sub-index

README.md
[![agentmods](https://agentmods.dev/badge/commands/ngerakines/jd/sub-index.svg)](https://agentmods.dev/commands/ngerakines/jd/sub-index)
Your own site
<a href="https://agentmods.dev/commands/ngerakines/jd/sub-index"><img src="https://agentmods.dev/badge/commands/ngerakines/jd/sub-index.svg" alt="Measured on agentmods" height="20"></a>
Per session 19 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 330 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 5.1 $0.00019 $0.00330
Opus 5 $0.00010 $0.00165
Sonnet 5 $0.00004 $0.00066
Haiku 4.5 $0.00002 $0.00033

Measured 6d ago against content hash 877bb70c76eb, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, from the pricing page.

Security

Grade A, and why

sub-index 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 6d 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.

jd/commands/sub-index.md · 46 lines

What it actually says

Manage +SUB Index

Scan a +SUB category, update its index file, and optionally create new +SUB entries with the next sequential number.

Arguments

$ARGUMENTS may contain:

  • A system code (e.g., P10) and category number (e.g., 51) to target a specific +SUB category.
  • Just a system code to list all +SUB categories in that system.
  • No arguments to discover all +SUB categories across all systems.

Workflow

  1. Locate the target +SUB category and its index file.
  2. Scan existing +SUB folders (matching AC.ID+NNNN or AC.ID+CODE).
  3. Compare folder entries against the index file.
  4. Update the index with any missing entries.
  5. Report the current state: total entries, active/archived counts, next available number.

Creating New Entries

When the user wants to add a new +SUB entry:

  1. Determine the next identifier (sequential number or user-provided code).
  2. Create the +SUB folder.
  3. Update the index file.
  4. Update the JDex.

Examples

/jd:sub-index
/jd:sub-index P10
/jd:sub-index P10 51
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. 6d ago First seen · 46 lines · 19 tokens per session scan A 877bb70c76eb

Subscribe to this mod's changes

sub-index is a command published in the GitHub repository ngerakines/jd (7 stars, last pushed 6mo ago), licensed Apache-2.0. It adds 19 tokens to every session and 330 once invoked, about $0.0001 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.