using-superctx

using-superctx is a skill for Claude Code from MrShininnnnn/SuperCtx. It costs 46 tokens per session (1,721 once invoked), scanned A, original, MIT.

Instructions for using a project-local context hub shared across coding tools. The hub stores canonical project guidance, while tool-specific files point to it.

In plain words
What is it for?
Use it when a repository contains a .ctx directory or when you need to inspect or update shared agent context and its generated tool-specific files.
Why use it?
It gives agents one maintained source of project instructions and explains how to handle synchronization, health checks, and repairs.

Skill for Claude Code

Written for Claude Code: shipped in a Claude Code plugin. Also seen: mentions CLAUDE.md; mentions AGENTS.md; mentions Codex.

Part of the superctx plugin — 3 skills, 3 hooks 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 skills/mrshininnnnn/superctx/using-superctx
Any agent
npx skills add MrShininnnnn/SuperCtx --skill using-superctx
Clone the repo
git clone --depth 1 https://github.com/MrShininnnnn/SuperCtx

Made for: Claude Code.

Or install superctx, the plugin that ships this one along with the rest of its 3 skills, 3 hooks.

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 using-superctx

README.md
[![agentmods](https://agentmods.dev/badge/skills/mrshininnnnn/superctx/using-superctx.svg)](https://agentmods.dev/skills/mrshininnnnn/superctx/using-superctx)
Your own site
<a href="https://agentmods.dev/skills/mrshininnnnn/superctx/using-superctx"><img src="https://agentmods.dev/badge/skills/mrshininnnnn/superctx/using-superctx.svg" alt="Measured on agentmods" height="20"></a>
Per session 46 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,721 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 $0.00046 $0.01721
Opus 5 $0.00023 $0.00860
Sonnet 5 $0.00009 $0.00344
Haiku 4.5 $0.00005 $0.00172

Measured 5d ago against content hash fbced75d00c9, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-05, from the pricing page.

Security

Grade A, and why

using-superctx 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 5d 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.

skills/using-superctx/SKILL.md · 116 lines

How it starts

The opening of the file, as written. The whole thing — 116 lines — stays where its author put it; the contents beside it link to each section on GitHub.

SuperCtx Reference Guide (Agent Reference / Advanced)

This is an agent reference and advanced skill. Normal users do not need to run this; the agent uses it automatically to orient itself on how to interact with the project-local SuperCtx context hub.

When to Use

Use this skill whenever:

  • A .ctx/ directory exists in the project root.
  • The user asks about project context, agent instructions, or tool configuration.
  • The user asks about sync, health, candidates, broken shims, or cross-tool context.
  • The user asks to update or apply context changes across agents.

Core Model

SuperCtx provides a central project-local context layer using a hub-and-shim model:

  • .ctx/SUPERCTX.md is the canonical project context hub.
  • Tool-specific instruction files (e.g. .claude/CLAUDE.md, .codex/AGENTS.md) are generated shims/adapters pointing to the hub.
  • .ctx/sources/ contains inactive recovery copies of original instruction files.

Edit Policy

When updating shared project context, the agent edits .ctx/SUPERCTX.md directly. The other managed files are not authoring surfaces.

File Policy
.ctx/SUPERCTX.md Author here. Canonical editable hub. Edit it to update shared project context. /superctx:sync preserves these edits.
Tool files (.claude/CLAUDE.md, .codex/AGENTS.md, .agy/ANTIGRAVITY.md, …) Generated shims. Do not edit. Edit .ctx/SUPERCTX.md instead.
.ctx/sources/** Backup only. Do not read, import, or edit as active context. Not live context.

Agent Rules

  1. Stay quiet about internals. Do not explain hub/shim/backup mechanics unless the user asks. Use SuperCtx context naturally without announcing how it works.
  2. Announce SuperCtx interactions. When SuperCtx is relevant or actively shaping the work, announce in one short sentence before taking action: Using SuperCtx to <purpose>. Keep the announcement task-specific.
  3. Do NOT ask users to manually edit manifest.toml or SUPERCTX.md, or manually run /superctx:sync or /superctx:add as the happy path unless they explicitly ask for commands. Prefer agent action and internal command execution. If /superctx:sync reports setup, add, repair, or migration opportunities, offer the action in natural language and ask for consent.
  4. Avoid saying "sync context" unless actually running /superctx:sync.
  5. Do NOT read, import, or edit .ctx/sources/** as active context. .ctx/sources/ contains inactive recovery copies of original pre-SuperCtx files. These files are for recovery and audit only, not canonical editable context. When updating project context, edit .ctx/SUPERCTX.md.
  6. Do NOT edit generated shims as the source of truth. Tool-specific files are thin generated pointers to .ctx/SUPERCTX.md.
  7. Use /superctx:sync for convergence. It handles initialization, health checks, and repairs.
  8. Offer agent-guided setup with explicit user consent when relevant. If a candidate repository is detected (no .ctx/ folder but candidate files exist), do not run /superctx:sync or mutate files without the user's explicit natural-language consent. Present the detected files, explain what setup will do, and ask for confirmation. Use this exact consent prompt:

    Using SuperCtx, I can set up one shared context hub for this repo.

    This will:

    • create .ctx/SUPERCTX.md
    • back up the original instruction files under .ctx/sources/
    • replace the live instruction files with generated shims pointing to the hub

    Proceed?

Read the full file on GitHub · 116 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. 5d ago First seen · 116 lines · 46 tokens per session scan A fbced75d00c9

Subscribe to this mod's changes

using-superctx is a skill published in the GitHub repository MrShininnnnn/SuperCtx (2 stars, last pushed 2mo ago), licensed MIT. It adds 46 tokens to every session and 1,721 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 2026-08-31.