| name | ascii-art-fix |
| description | Fix misaligned right borders in ASCII art diagrams |
| license | Apache-2.0 |
| disable-model-invocation | true |
| metadata | {"status":"experimental","experimental_reason":"Prompt-only repair is useful but still has edge cases around nested diagrams, tables, and mixed markdown content."} |
ASCII Art Fix
Fix misaligned right borders in ASCII art box diagrams. Prompt-driven — no external tools required.
Recognizing ASCII Box Diagrams
Box diagrams use border characters to draw rectangular outlines:
Plus-dash style:
+-------------------+
| Content here |
+-------------------+
Unicode style:
┌─────────────────┐
│ Content here │
└─────────────────┘
How to Fix
- Find each box — identify top/bottom borders (lines of
+---+ or ┌───┐ / └───┘)
- Measure the box width — count characters in the top border from first
+ to last + (inclusive)
- Pad each content line — every
| or │ content line between borders must have its closing border character at the same column as the border width
- Preserve everything else — do not modify any text outside box diagrams
Rules
DO fix:
- Content lines where the closing
| or │ is at the wrong column
- Pad with spaces between content and closing border
DO NOT touch:
- Markdown tables (
| Col | Col | with |---|---| separator rows)
- Content inside fenced code blocks (``` or ~~~)
- Flow arrows or connectors between boxes (
|, v, ---->)
- Lines that don't belong to a box diagram
- Already-aligned boxes
Distinguishing Tables from Boxes
Markdown tables have:
- Multiple
| characters per line separating columns
- A separator row matching
|---|---| (dashes with optional colons)
- No
+ corner characters
Box diagrams have:
+ or ┌└┐┘ corner characters on border lines- Exactly two
| or │ per content line (opening and closing)
- Horizontal borders made of
- or ─
If a line has a |---| separator row, it's a table. Leave it alone.
Verify Your Work
After fixing, check that every line in each box is the same width. Nested boxes are especially tricky — the outer box content lines that contain an inner box still need their closing | at the outer box's column:
+------------------+ <- width 20, | at column 20
| Outer content | <- | at column 20 ✓
| +----------+ | <- | at column 20 ✓ (not column 17)
| | Inner | | <- | at column 20 ✓
| +----------+ | <- | at column 20 ✓
+------------------+
Run the validator to catch misalignment:
python3 scripts/validate.py <file>
Eval
Run the eval to check your work:
bash skills/ascii-art-fix/scripts/clean.sh
bash skills/ascii-art-fix/scripts/eval.sh
See references/evaluating.md for the full eval workflow.
