A deployable-behavior Cursor plugin that ships an always-apply rule making the agent add language-idiomatic inline documentation whenever it writes, modifies, or creates code. Unlike the initializer and customizer plugins in this marketplace, this plugin delivers behavior on install — no artifact generation step required.
The plugin bundles one always-apply rule and two manual-only skills:
document-as-you-coderule — active on every turn, instructs the agent to add idiomatic documentation in the correct format for each language, including scripts.code-explainskill — deliberate, on-demand explanation of existing code sections.doc-generateskill — deliberate, on-demand generation of documentation for a file or module.
The document-as-you-code rule is always-apply and injects a small, fixed
prompt into every agent turn. Its token cost is negligible — roughly 30 tokens
per turn regardless of project size.
The two manual skills (code-explain, doc-generate) perform heavier analysis
and are invoked explicitly. Their cost scales with the size of the code section
or file being documented.
Recommended model: any capable frontier model works well for the always-apply rule. For the manual skills, a frontier balanced model with high effort delivers good documentation quality at reasonable cost; a frontier reasoning model is the better choice for large or complex codebases.
Usage pattern: install once, leave the rule active. Invoke the manual skills when you need comprehensive documentation for an existing file or module — not on every session.
Agents write undocumented code by default. Adding a documentation instruction
after the fact either goes unnoticed or requires a separate prompt every
session. An always-apply rule is the only reliable per-turn injection surface
in Cursor (verified against official docs and Cursor forum 2026-06-21:
beforeSubmitPrompt is block-only, afterFileEdit cannot feed the model, and
sessionStart injection is currently broken).
Shipping the rule as a plugin artifact means the behavior travels with the plugin, loads on install, and applies without any per-project configuration.
For local development and testing, load this repository through Cursor's local plugin directory:
# Clone the repository
git clone https://github.com/rodrigorjsf/agent-engineering-toolkit.git ~/src/agent-engineering-toolkit
# Register as a local Cursor plugin marketplace
mkdir -p ~/.cursor/plugins/local
ln -s ~/src/agent-engineering-toolkit ~/.cursor/plugins/local/agent-engineering-toolkitThen restart Cursor (or run Developer: Reload Window). The repo root
.cursor-plugin/marketplace.json exposes cursor-code-documentation alongside
the other plugins in this marketplace.
The document-as-you-code rule is always active after installation — no
invocation required.
The manual skills are invoked explicitly:
/cursor-code-documentation:code-explain # explain an existing code section
/cursor-code-documentation:doc-generate # generate documentation for a file or module
The document-as-you-code rule is always active after installation; the two
manual skills ship alongside it and are invoked explicitly.
plugins/cursor-code-documentation/
├── .cursor-plugin/
│ └── plugin.json # Plugin manifest (name, version, description)
├── .cursor/
│ └── rules/
│ └── document-as-you-code.mdc # Always-apply documentation rule
└── skills/
├── code-explain/
│ └── SKILL.md # Manual-only: explain an existing code section
└── doc-generate/
└── SKILL.md # Manual-only: generate documentation for a file or module
MIT