open-agent-hub: Instructions file for Gemini CLI

GEMINI.md

open-agent-hub GEMINI.md is an instructions file for Gemini CLI from guanyang/open-agent-hub. It costs 485 tokens per session, scanned A, a copy of open-agent-hub AGENTS.md, MIT.

A set of instructions for an AI coding agent covering planning, simplicity, careful edits, and working toward a clear goal. It is provided as a GEMINI.md project guidance file.

In plain words
What is it for?
Use it to guide an agent before and during coding, especially when deciding what to change, how much code to write, and whether to ask about unclear requirements.
Why use it?
It helps reduce unnecessary code changes, hidden assumptions, and overcomplicated solutions during development.

Instructions file for Gemini CLI

Written for Gemini CLI: the file is GEMINI.md. Also seen: mentions Gemini CLI.

This is guanyang/open-agent-hub's own configuration. It tells Gemini CLI how to work on open-agent-hub 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 open-agent-hub configures →

Reuse

Borrowing it

Nothing to install: this file belongs to guanyang/open-agent-hub. 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/guanyang/open-agent-hub/main/GEMINI.md
Clone the repo
git clone --depth 1 https://github.com/guanyang/open-agent-hub

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 open-agent-hub GEMINI.md

README.md
[![agentmods](https://agentmods.dev/badge/instructions/guanyang/open-agent-hub/gemini-md.svg)](https://agentmods.dev/instructions/guanyang/open-agent-hub/gemini-md)
Your own site
<a href="https://agentmods.dev/instructions/guanyang/open-agent-hub/gemini-md"><img src="https://agentmods.dev/badge/instructions/guanyang/open-agent-hub/gemini-md.svg" alt="Measured on agentmods" height="20"></a>
Per session 485 This file is loaded in full into every session.
When invoked 485 The same file — it is already loaded in full.
Security scan A 0 findings. Scan, not verified.
Origin 98% copy Near-identical to another mod 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 $0.00485 $0.00485
Opus 5 $0.00243 $0.00243
Sonnet 5 $0.00097 $0.00097
Haiku 4.5 $0.00049 $0.00049

Measured 6d ago against content hash 2f02ad288096, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, from the pricing page.

Security

Grade A, and why

open-agent-hub 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 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.

Origin

This is a copy

98% identical to open-agent-hub AGENTS.md — 3 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

GEMINI.md · 67 lines

How it starts

The opening of the file, as written. The whole thing — 67 lines — stays where its author put it; the contents beside it link to each section on GitHub.

GEMINI.md

Behavioral guidelines to reduce common LLM coding mistakes. Merge with project-specific instructions as needed.

Tradeoff: These guidelines bias toward caution over speed. For trivial tasks, use judgment.

1. Think Before Coding

Don't assume. Don't hide confusion. Surface tradeoffs.

Before implementing:

  • State your assumptions explicitly. If uncertain, ask.
  • If multiple interpretations exist, present them - don't pick silently.
  • If a simpler approach exists, say so. Push back when warranted.
  • If something is unclear, stop. Name what's confusing. Ask.

2. Simplicity First

Minimum code that solves the problem. Nothing speculative.

  • No features beyond what was asked.
  • No abstractions for single-use code.
  • No "flexibility" or "configurability" that wasn't requested.
  • No error handling for impossible scenarios.
  • If you write 200 lines and it could be 50, rewrite it.

Ask yourself: "Would a senior engineer say this is overcomplicated?" If yes, simplify.

3. Surgical Changes

Touch only what you must. Clean up only your own mess.

When editing existing code:

  • Don't "improve" adjacent code, comments, or formatting.
  • Don't refactor things that aren't broken.
  • Match existing style, even if you'd do it differently.
  • If you notice unrelated dead code, mention it - don't delete it.

When your changes create orphans:

  • Remove imports/variables/functions that YOUR changes made unused.
  • Don't remove pre-existing dead code unless asked.

The test: Every changed line should trace directly to the user's request.

4. Goal-Driven Execution

Define success criteria. Loop until verified.

Transform tasks into verifiable goals:

  • "Add validation" → "Write tests for invalid inputs, then make them pass"
  • "Fix the bug" → "Write a test that reproduces it, then make it pass"
  • "Refactor X" → "Ensure tests pass before and after"

For multi-step tasks, state a brief plan:

1. [Step] → verify: [check]
2. [Step] → verify: [check]
3. [Step] → verify: [check]

Read the full file on GitHub · 67 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. 6d ago First seen · 67 lines · 485 tokens per session scan A 2f02ad288096

Subscribe to this mod's changes

open-agent-hub GEMINI.md is an instructions file published in the GitHub repository guanyang/open-agent-hub (959 stars, last pushed today), licensed MIT. It adds 485 tokens to every session, about $0.0024 per session on Opus 5. A static security scan graded it A with 0 findings. It is 98% identical to open-agent-hub AGENTS.md, differing in 3 lines, and is treated as a copy.

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