create_jinx

create_jinx is a skill for Claude Code, Codex from NPC-Worldwide/npcpy. It costs 78 tokens per session (292 once invoked), scanned A, original, MIT.

A tool that creates a reusable .jinx file from a name, description, input list, and Python code.

In plain words
What is it for?
Use it to save reusable Python-based helpers in the team's jinx library and register them for immediate use.
Why use it?
It turns a repeated block of code into a callable team utility without requiring a restart.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one.

About the project

npcpy is a Python library for building applications with multimodal language models, agent-based AI, and knowledge graphs. Researchers and developers use it with local or cloud model providers to create agents, multi-agent teams, and AI workflows.

NPC-Worldwide/npcpy · 1,497 stars · on GitHub

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/npc-worldwide/npcpy/create_jinx
Any agent
npx skills add NPC-Worldwide/npcpy --skill create_jinx
Clone the repo
git clone --depth 1 https://github.com/NPC-Worldwide/npcpy

Made for: Claude Code, Codex.

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 create_jinx

README.md
[![agentmods](https://agentmods.dev/badge/skills/npc-worldwide/npcpy/create_jinx.svg)](https://agentmods.dev/skills/npc-worldwide/npcpy/create_jinx)
Your own site
<a href="https://agentmods.dev/skills/npc-worldwide/npcpy/create_jinx"><img src="https://agentmods.dev/badge/skills/npc-worldwide/npcpy/create_jinx.svg" alt="Measured on agentmods" height="20"></a>
Per session 78 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 292 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 $0.00078 $0.00292
Opus 5 $0.00039 $0.00146
Sonnet 5 $0.00016 $0.00058
Haiku 4.5 $0.00008 $0.00029

Measured 6d ago against content hash 1b696ed8477d, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, from the pricing page.

Security

Grade A, and why

create_jinx 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.

The scan reads SKILL.md. This mod also ships 1 executable file (write_jinx.py), 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.

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/create_jinx/SKILL.md · 31 lines

What it actually says

create_jinx

Write a new .jinx file from inputs (name, description, inputs spec as JSON list of strings, python body). Agents use this mid-task to crystallize a repeated block of code into a reusable jinx. The jinx is written to the team's jinxes/lib dir by default and registered with the running team so it is immediately callable without a restart.

Inputs

  • jinx_name
  • description
  • inputs_spec (default: '[]')
  • python_code
  • target_subdir (default: 'lib')

Steps

Usage

/run_jinx jinx_ref=create_jinx input_values={"jinx_name": "<value>", "description": "<value>", "inputs_spec": "[]", "python_code": "<value>", "target_subdir": "lib"}
Files

What ships with it

1 file 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. 6d ago First seen · 31 lines · 78 tokens per session scan A 1b696ed8477d

Subscribe to this mod's changes

create_jinx is a skill published in the GitHub repository NPC-Worldwide/npcpy (1,497 stars, last pushed 2d ago), licensed MIT. It adds 78 tokens to every session and 292 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.