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katana: Instructions file for Codex

AGENTS.md

katana AGENTS.md is an instructions file for Codex, OpenCode from vgmakeev/katana. It costs 397 tokens per session, scanned A, original, Apache-2.0.

Project instructions for Katana, a deterministic tool that analyses and applies code refactoring plans across different programming languages and toolchains. They define its runtime, ownership boundaries, compatibility requirements, and agent contract.

In plain words
What is it for?
Use them when changing Katana's document model, planning or applying refactors, language and tool adapters, command protocols, CLI behavior, or compatibility tests.
Why use it?
They reduce the risk of breaking existing command formats, language adapters, formatting tools, or safety rules when modifying Katana.

Instructions file for CodexOpenCode

Written for Codex and OpenCode: the file is AGENTS.md.

This is vgmakeev/katana's own configuration. It tells Codex and OpenCode how to work on katana 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 katana configures →

not rated 12repo yesterday A scan 397 tokens original Apache-2.0
View source ↗ vgmakeev/katana
Reuse

Borrowing it

Nothing to install: this file belongs to vgmakeev/katana. 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/vgmakeev/katana/main/AGENTS.md
Clone the repo
git clone --depth 1 https://github.com/vgmakeev/katana

Made for: Codex, OpenCode.

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.

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README.md
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Your own site
<a href="https://agentmods.dev/instructions/vgmakeev/katana/agents-md"><img src="https://agentmods.dev/badge/instructions/vgmakeev/katana/agents-md/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for katana AGENTS.md

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<a href="https://agentmods.dev/instructions/vgmakeev/katana/agents-md"><img src="https://agentmods.dev/badge/instructions/vgmakeev/katana/agents-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 397 This file is loaded in full into every session.
When invoked 397 The same file — it is already loaded in full.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
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 $0.00397 $0.00397
Opus 5.5 $0.00159 $0.00159
Sonnet 5.5 $0.00079 $0.00079
Haiku 4.5 $0.00040 $0.00040

Measured 2mo ago against content hash d90329bc4940, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

katana AGENTS.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 2mo 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.

AGENTS.md · 46 lines

What it actually says

Agent instructions

Katana is an agent-first, deterministic polyglot refactoring executor.

Runtime

  • Use Python 3.14.
  • Install with uv sync --all-groups.
  • Run the complete gate with make check.
  • Run make markdown-check when the Node bridge changes.

Boundaries

  • Core owns DocumentIR, plans, conformance, apply orchestration, and the CLI.
  • Language behavior belongs in katana.adapters.<stack> or an external package registered under katana.adapters.
  • Formatter, lint-fix, and checker behavior belongs in katana.toolchains.<stack> or katana.toolchains entry points.
  • Built-in adapters use the same public contracts as third-party adapters.
  • Command adapter protocol v1 is analysis-only and must fail rewrite closed.

Compatibility

  • Preserve split-plan v1 and existing schema, outline, assess, plan, apply, large, and project JSON behavior.
  • Keep legacy adapter ids node_typescript, dart_analyzer, and node_postcss.
  • Existing public functions remain compatibility facades over adapters.
  • Add conformance and regression tests for protocol changes.

Agent contract

  • Never include source bodies in DocumentIR or other agent maps.
  • Keep commands non-interactive and machine-readable.
  • Prefer exact hashes and byte spans over parser-specific node objects.
  • Analysis-only support is useful; do not claim rewrite capabilities without dependency closure, import handling, formatting, and validation.
  • Preserve source bytes during mechanical moves. Semantic changes are separate.

Source budget

  • Keep source files within 500 physical and language-aware code lines.
  • The hard repository ceiling is 500 lines.
  • make size-check enforces both measures across runtime, tests, and examples.
  • Split by cohesive responsibility before raising the ceiling or adding exclusions.
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. 2mo ago First seen · 46 lines · 397 tokens per session scan A d90329bc4940

Subscribe to this mod's changes

katana AGENTS.md is an instructions file published in the GitHub repository vgmakeev/katana (12 stars, last pushed yesterday), licensed Apache-2.0. It adds 397 tokens to every session, about $0.0016 per session on Opus 5.5. 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.

ai-agentsastclicode-intelligencedeveloper-toolsrefactoring
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katana AGENTS.md next to 6 instructions from other repositories
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katana AGENTS.mdvgmakeev/katanaInstructions file12yesterdayApache-2.0A397Codex, OpenCode
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next.js AGENTS.mdvercel/next.jsInstructions file143kyesterdayMITA7,461Codex, OpenCode
langchain AGENTS.mdlangchain-ai/langchainInstructions file149kyesterdayMITA4,680Codex, OpenCode