[Controlled Czech]

An open specification for clear, unambiguous and machine-checkable technical Czech. Rules, a CI linter and a plugin for AI agents.

Technical text should transfer information with minimal reader effort. Natural Czech does not enforce information density, and generative models reduce it further: the output is grammatically correct but longer than its content warrants. Controlled Czech defines rules that enforce density, plus a linter that finds violations in CI.

Same information, less text

Before

Plain

V rámci nasazení nové verze bychom měli ideálně zajistit, aby se migrace
provedla až poté, co budou dokončeny všechny běžící úlohy, protože jinak
může dojít k nekonzistenci dat.

After

Plain

Před nasazením dokončete všechny běžící úlohy. Potom spusťte migraci.
Pokud migraci spustíte dříve, data mohou být nekonzistentní.

The examples stay in Czech: they are the subject of the specification. Same information, three short sentences, explicit order of steps.

What Controlled Czech enforces

Information before style. The answer first, one idea per sentence, an explicit actor, one term per concept. No introductions that carry no new information.

Stable CCxxx rules. Every rule has an identifier. Linter diagnostics, pull request reviews and agent instructions all point to the same number.

Linter for CI. A deterministic tool written in Go, a single binary with no dependencies. It runs offline, uses no LLM and never rewrites your text. In CI it fails on warnings with --fail-on-warning.

Plugin for AI agents. A skill for Claude Code, Codex and ChatGPT. The agent loads only the skill description into context. It loads the full rules when it works with Czech text.

Where to use it

technical documentation,
specifications and assignments,
ADRs and other technical decisions,
issues and pull requests,
runbooks and operating procedures,
AI agent instructions.

Controlled Czech is not a general Czech style guide. Do not use it for marketing, fiction or personal communication.

Getting started

Install

Shell

# Claude Code
/plugin marketplace add sinfin/controlled-czech
/plugin install controlled-czech@sinfin

# Linter
go install github.com/sinfin/controlled-czech/cmd/controlled-czech@latest
controlled-czech check docs/

The specification, the CCxxx rules, examples and templates live on GitHub. The linter is MIT licensed, the specification is CC BY 4.0.

Plugin for Codex and ChatGPT

Controlled Czech as a plugin from the GPT marketplace. One install, no configuration.

Open on the marketplace

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