Cron Sense

Translate cron-like schedules into human-readable English inside Zed.

Extension ID: cron-sense-lsp
Marketplace: zed.dev/extensions/cron-sense-lsp

Inspired by the VS Code extension Cron Explained by Tom Coufal (@tumido) (VS Marketplace, Open VSX).

This is an independent, from-scratch reimplementation for Zed. It is not a fork of the original source and is not affiliated with the original author beyond credit for the concept and UX.

Install

From the Zed extension marketplace

Open the Cron Sense extension page, or in Zed open Extensions (zed: extensions from the command palette) and search for Cron Sense.
Click Install (or use Install in Zed from the marketplace page).

On first use, the extension installs the language server from npm as cron-sense-lsp. That package includes the server script and its dependencies (cronstrue, vscode-languageserver, …).

Dev extension (local development)

Clone or open this repository.
In Zed: Extensions → Install Dev Extension…
Select the cron-sense directory.

Features

Hover tooltips

Hover a cron expression in supported languages and get a plain-English explanation powered by cronstrue.

Supported language contexts include Shell Script, YAML, TOML, JSON, Dockerfile, JavaScript/TypeScript, Python, Ruby, Go, Rust, Markdown, and Plain Text.

Code action: insert as comment

Open the code actions menu on a cron expression (default: cmd-. / ctrl-.) and choose Insert cron explanation to append a comment on that line. Running it again replaces the previous explanation (no stacked comments).

Settings

Optional LSP settings in your Zed settings.json:

{
  "lsp": {
    "cron-sense-lsp": {
      "settings": {
        "use24HourTimeFormat": true,
        "verbose": true,
        "dayOfWeekStartIndexZero": true,
        "monthStartIndexZero": false,
        "locale": "en"
      }
    }
  }
}

Setting	Description	Default
`use24HourTimeFormat`	Use 24-hour clock in descriptions	`true`
`verbose`	Prefer verbose descriptions	`true`
`dayOfWeekStartIndexZero`	Day-of-week `1` = Monday (`true`) or Sunday (`false`, e.g. AWS)	`true`
`monthStartIndexZero`	January as `0` vs `1`	`false`
`locale`	Force a cronstrue locale	(unset)

How it works

Piece	Implementation
Extension (Wasm)	Resolves Node, installs `cron-sense-lsp` from npm via Zed APIs
Language server	Node package `cron-sense-lsp` (`server/server.cjs` + deps)

The language server is not embedded in the extension package (Zed publishing requirement). Source lives in server/ and is published to the public npm registry.

Development

Requirements: Rust (with wasm32-wasip2 via rustup), Node, Zed.

# Typecheck / test the extension crate
cargo test --lib
cargo check --target wasm32-wasip2

# Smoke-test the language server locally
cd server && npm install && npm test
# or speak LSP over stdio:
npm start

Publishing the language server (npm)

cd server
npm login          # once
npm version patch  # or set version in package.json
npm publish --access public

Keep server/package.json version aligned with the extension when cutting a release that depends on new server behavior.

Cutting an extension release

Bump version in extension.toml and Cargo.toml (keep them equal).
Ensure the matching cron-sense-lsp version is on npm (or rely on latest).
Tag vX.Y.Z on this repo.
Open/update a PR on zed-industries/extensions with submodule extensions/cron-sense-lsp and matching version in extensions.toml.

Credits & acknowledgements

Inspiration

Cron Explained for VS Code / Open VSX
Author: Tom Coufal (@tumido)
License: GPL-3.0-or-later

Please support and star the original if you find the concept useful.

Libraries

Translations: cronstrue by Brady Holt
LSP stack: vscode-languageserver

License

This repository is licensed under the MIT License.

That applies to this project’s code only. The original tumido/cron-explained project remains GPL-3.0-or-later under its own license.