ggterm-customize - SKILL.md Agent Skill

name: ggterm-customize description: Customize plot aesthetics using natural language. Use when the user wants to change colors, fonts, titles, labels, themes, or any visual aspect of a plot before publication. allowed-tools: Read, Write, Bash(npx:*)

Natural Language Plot Customization

Modify Vega-Lite specifications based on natural language requests.

CRITICAL: Which File to Edit

ALWAYS read and write .ggterm/last-plot-vegalite.json — this is the Vega-Lite spec that the viewer renders.

NEVER modify .ggterm/last-plot.json — that is the ggterm terminal format. Changes to it will NOT appear in the viewer.

Common Customizations

All examples below modify properties of the Vega-Lite spec read from .ggterm/last-plot-vegalite.json:

Title and Labels

spec.title = "New Title"
spec.title = { text: "Title", subtitle: "Subtitle" }
spec.encoding.x.title = "X Axis Label"
spec.encoding.y.title = "Y Axis Label"
spec.encoding.color.title = "Legend Title"

Colors

spec.encoding.color.scale = { scheme: "category10" }  // categorical
spec.encoding.color.scale = { scheme: "viridis" }     // continuous
spec.mark.color = "#3366cc"                            // single color

Fonts and Config

spec.config = spec.config || {}
spec.config.font = "Helvetica"
spec.config.title = { fontSize: 18, fontWeight: "bold" }
spec.config.axis = { labelFontSize: 12, titleFontSize: 14 }

Dimensions

spec.width = 600
spec.height = 400

Workflow

Read .ggterm/last-plot-vegalite.json (NOT last-plot.json)
Parse as JSON, apply the requested modifications
Write the updated JSON back to .ggterm/last-plot-vegalite.json
DONE — the live viewer auto-detects the change and displays the customized plot

IMPORTANT: Do NOT re-create the plot with npx ggterm-plot after customizing. The viewer watches the spec file and auto-updates. Re-running the plot command would overwrite your customizations.

$ARGUMENTS