| name | ascii-rendering |
| description | This skill should be used when the user asks to "draw a diagram", "show a status box", "render ASCII art", "make a callout", "wrap text in a box", "plot these numbers", or any request involving boxed messages, two-box-and-arrow diagrams, scatter plots, or tables rendered as ASCII. Uses JBang to invoke the JaiClaw ASCII renderer; do not hand-draw borders character-by-character. |
| version | 0.1.0 |
ASCII Rendering
This skill lets you render structured ASCII art instead of hand-drawing
borders character-by-character. Two scripts under scripts/, both
JBang-shebanged so they self-resolve their Maven dependency on first
run.
When to use
Use this skill whenever the user asks for:
- A boxed status message, callout, or warning
- A simple diagram (two or three boxes joined by lines)
- A scatter plot of numbers
- A table grid
- "Draw me X in ASCII"
Do not use it when the user wants rich HTML, interactive UI, or
images — those need a different tool.
What's here
scripts/RenderBox.java — quick wrapper for "put this text in a box"scripts/RenderScene.java — full scene renderer (rectangles, lines,
labels, text blocks, dots, circles, ellipses, tables, scatter plots)examples/*.json — three reference scenes you can adapt
How to invoke
Quick boxed message — RenderBox.java
jbang ${CLAUDE_PLUGIN_ROOT}/skills/ascii-rendering/scripts/RenderBox.java --content "Build green — all tests pass." \
--title=STATUS --border=double
Output (stdout):
╔════════════════════════════════════════════════════════════╗
║[ STATUS ] ║
║Build green — all tests pass. ║
╚════════════════════════════════════════════════════════════╝
Flags:
| Flag | Default | Notes |
|---|
--content TEXT or --file PATH or stdin | — | Source text |
--width N | 60 | Max inner width (clamped to [4, 500]) |
--border single|double|bold|rounded | single | Border style |
--title TEXT | — | Top-edge banner [ TEXT ] |
Structured scene — RenderScene.java
Write the scene JSON to a temp file, then:
jbang ${CLAUDE_PLUGIN_ROOT}/skills/ascii-rendering/scripts/RenderScene.java --file /tmp/scene.json
Or pipe via stdin:
echo '{"width":40,"height":5,"elements":[{"type":"rectangle"}]}' | \
jbang ${CLAUDE_PLUGIN_ROOT}/skills/ascii-rendering/scripts/RenderScene.java
Scene JSON shape
{
"width": 40,
"height": 5,
"trim": true,
"elements": [
{"type": "rectangle"},
{"type": "label",
"params": {"text": "Hello", "x": 15, "y": 2}}
]
}
Element catalogue
Coordinates: origin (0, 0) at top-left; x grows right, y grows down.
Position keys are optional — omitting them centres or fills automatically.
type | Required params | Optional params |
|---|
rectangle | — | x, y, width, height |
line | x1, y1, x2, y2 | pen (single char, default ●) |
label | text | x, y, width (single line; truncated with …) |
text | text | x, y, width, height (multi-line; word-wraps) |
dot | — | x, y |
circle | — | x, y, radius |
ellipse | — | x, y, width, height |
table | rows, columns (both > 0) | x, y, width, height |
plot | points (list of [x, y]), width, height (> 0) | x, y |
Look at ${CLAUDE_PLUGIN_ROOT}/skills/ascii-rendering/examples/boxed-hello.json,
call-graph.json, and scatter-plot.json in the same directory for
full reference scenes.
Errors
Bad input prints to stderr with a precise location, then exits non-zero:
[element 3]: 'columns' and 'rows' must be positive.[element 2]: Unknown element type 'marshmallow'.Missing or non-positive 'width'.
When you see one, fix the indicated element and retry the script.
Don't try to hand-render the result; the script is the authoritative
renderer.
Prerequisites
The host must have JBang installed (brew install jbang /
curl -Ls https://sh.jbang.dev | bash). JBang manages Java
automatically; no separate Java install needed.
First invocation pulls the jaiclaw-ascii-render jar + Jackson +
SLF4J from Maven (~3 MB total) and caches them under
~/.jbang/cache/. Subsequent calls start in well under a second.
