spellbook GEMINI.md

spellbook GEMINI.md is an instructions file for Gemini CLI from axiomantic/spellbook. It costs 21 tokens per session, scanned A, original, MIT.

A project instruction that tells the coding agent to read AGENTS.md, a file containing project rules, before working.

In plain words
What is it for?
Use it in projects whose instructions are stored in AGENTS.md.
Why use it?
It helps the agent follow the repository's existing development and contribution guidelines.

Instructions file for Gemini CLI

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 instructions/axiomantic/spellbook/gemini-md
Clone the repo
git clone --depth 1 https://github.com/axiomantic/spellbook

Made for: Gemini CLI.

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 spellbook GEMINI.md

README.md
[![agentmods](https://agentmods.dev/badge/instructions/axiomantic/spellbook/gemini-md.svg)](https://agentmods.dev/instructions/axiomantic/spellbook/gemini-md)
Your own site
<a href="https://agentmods.dev/instructions/axiomantic/spellbook/gemini-md"><img src="https://agentmods.dev/badge/instructions/axiomantic/spellbook/gemini-md.svg" alt="Measured on agentmods" height="20"></a>
Per session 21 This file is loaded in full into every session.
When invoked 21 The same file — it is already loaded in full.
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 $0.00021 $0.00021
Opus 5 $0.00010 $0.00010
Sonnet 5 $0.00004 $0.00004
Haiku 4.5 $0.00002 $0.00002

Measured 4d ago against content hash 3d71919969c1, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

spellbook GEMINI.md 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 4d 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.

GEMINI.md · 4 lines

What it actually says

Spellbook Development

Read and follow the instructions in AGENTS.md.

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. 4d ago First seen · 4 lines · 21 tokens per session scan A 3d71919969c1

Subscribe to this mod's changes

spellbook GEMINI.md is an instructions file published in the GitHub repository axiomantic/spellbook (10 stars, last pushed today), licensed MIT. It adds 21 tokens to every session, 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.