fix-nested-code-fences

name	fix-nested-code-fences
description	Use when a markdown file has nested code fences that break rendering — when a ```markdown, ```bash, or similar block appears inside another ``` block anywhere in a generated or edited markdown file.

Skill: fix-nested-code-fences

When a code block contains inner triple-backtick fences, replace the outer fence with ~~~ — the minimum change that fixes rendering without altering any content.

Don't: change inner fences — only the outer fence needs replacing. Don't apply this to tilde fences that are already correct.

The Problem

When markdown is generated or written that contains code block examples inside other code blocks, the inner fences terminate the outer block early, breaking rendered output. Common in: skill templates, documentation generators, README examples, any file where markdown is shown inside markdown.

The Fix

Replace the outer fence with ~~~ when the block contains inner ``` fences. Inner fences stay as-is.

Before:

```markdown
## Example

```bash
VAR=value
```
```

After:

~~~markdown
## Example

```bash
VAR=value
```
~~~

Steps

1. Read the file
2. Find any fenced code block that contains inner ``` fences
3. Replace the outer opening and closing fences with ~~~
4. Leave inner fences unchanged
5. Confirm the fix and offer to commit if in a git repo