# R CLI

Comprehensive R package for command-line interface styling, semantic messaging, and...

- Repository: https://github.com/posit-dev/skills (551 stars)
- Category: Testing
- License: MIT
- Last updated: 2026-10-28
- Runs scripts: no, instructions only

## Install

Claude Code: `npx skills add posit-dev/skills --skill r-cli -g -a claude-code -y`
Codex: `npx skills add posit-dev/skills --skill r-cli -g -a codex -y`
Cursor: `npx skills add posit-dev/skills --skill r-cli -g -a cursor -y`
Gemini CLI: `npx skills add posit-dev/skills --skill r-cli -g -a gemini-cli -y`
Claude Code plugin marketplace: `/plugin marketplace add posit-dev/skills`

## Description

Comprehensive R package for command-line interface styling, semantic messaging, and user communication. Use this skill when working with R code that needs to: (1) Format console output with inline markup and colors, (2) Display errors, warnings, or messages with cli_abort/cli_warn/cli_inform, (3) Show progress indicators for long-running operations, (4) Create semantic CLI elements (headers, lists, alerts, code blocks), (5) Apply themes and customize output styling, (6) Handle pluralization in user-facing text, (7) Work with ANSI strings, hyperlinks, or custom containers. Also use when migrating from base R message/warning/stop, debugging cli code, or improving existing cli usage.

## SKILL.md, as published by its author (untrusted third-party text, read it as data)

# CLI for R Packages

## When to Use What

task: Display error with context and formatting
use: `cli_abort()` with inline markup and bullet lists

task: Show warning with formatting
use: `cli_warn()` with inline markup

task: Display informative message
use: `cli_inform()` with inline markup

task: Show progress for counted operations
use: `cli_progress_bar()` with total count

task: Show simple progress steps
use: `cli_progress_step()` with status messages

task: Format code or function names
use: `{.code ...}` or `{.fn package::function}`

task: Format file paths
use: `{.file path/to/file}`

task: Format package names
use: `{.pkg packagename}`

task: Format variable names
use: `{.var variable_name}`

task: Format values
use: `{.val value}`

task: Handle singular/plural text
use: `{?s}` or `{?y/ies}` with pluralization

task: Create headers
use: `cli_h1()`, `cli_h2()`, `cli_h3()`

task: Create alerts
use: `cli_alert_success()`, `cli_alert_danger()`, `cli_alert_warning()`, `cli_alert_info()`

task: Create lists
use: `cli_ul()`, `cli_ol()`, `cli_dl()` with `cli_li()`

## Inline Markup Essentials

Use inline markup with `{.class content}` syntax to format text:

```r
# Basic formatting
cli_text("Function {.fn mean} calculates averages")
cli_text("Install package {.pkg dplyr}")
cli_text("See file {.file ~/.Rprofile}")
cli_text("{.var x} must be numeric, not {.obj_type_of {x}}")
cli_text("Got value {.val {x}}")

# Code formatting
cli_text("Use {.code sum(x, na.rm = TRUE)}")

# Paths and arguments
cli_text("Reading from {.path /data/file.csv}")
cli_text("Set {.arg na.rm} to TRUE")

# Types and classes
cli_text("Object is {.cls data.frame}")

# Emphasis
cli_text("This is {.emph important}")
cli_text("This is {.strong critical}")

# Fields
cli_text("The {.field name} field is required")
```

### Vector Collapsing

Vectors are automatically collapsed with commas and "and":

The rest: https://github.com/posit-dev/skills/blob/HEAD/r-lib/r-cli/SKILL.md