markdown-it-sub

This is one of those plugins that just works. Integration is dead simple - just `md.use(require('markdown-it-sub'))` and you're done. The syntax (`H~2~O` becomes H₂O) is intuitive and follows the same pattern as markdown-it-sup, making it easy to remember if you use both.

The package has zero configuration options, which is actually a strength here since subscript formatting doesn't need customization. TypeScript definitions are included out of the box and work seamlessly with markdown-it's types. Error handling is non-existent because there's nothing that can really go wrong - invalid syntax just renders as-is, which is the expected behavior.

The main limitation is documentation sparseness. The README shows basic usage but doesn't explain edge cases like nested tildes or interaction with other markdown-it plugins. That said, the plugin is so straightforward that you'll rarely need docs beyond the initial setup example.

This is exactly what a focused markdown-it plugin should be. Setup is literally two lines: require the plugin and call `.use()` on your markdown-it instance. The syntax (~text~) is intuitive if you're already familiar with markdown-it's superscript plugin or similar markup patterns. I had it working in under a minute without reading documentation.

The error handling is essentially nonexistent, but that's actually fine for this use case - if the syntax doesn't match, it just renders as plain text, which is predictable behavior. No cryptic errors to debug. The main gotcha is remembering that tildes need to be escaped if you actually want literal tildes, but this is consistent with how markdown-it handles other special characters.

Documentation is minimal but sufficient - the README shows the basic usage and syntax example. There's not much else to document given the simplicity. Community support isn't really needed since there's almost nothing that can go wrong. It integrates seamlessly with other markdown-it plugins without conflicts.

This is exactly what a markdown-it plugin should be: minimal, focused, and predictable. Integration is literally two lines—require it and call `.use()` on your markdown-it instance. Zero configuration needed unless you want to customize the marker syntax. Runtime overhead is negligible since it's a simple regex-based pattern replacement that hooks into markdown-it's parsing phase.

The plugin handles edge cases reasonably well (nested markup, escaping) and doesn't introduce memory leaks or performance issues even with large documents. No connection pooling or resource management concerns here—it's stateless transformation logic. Error handling is inherited from markdown-it itself, which means parse errors fail gracefully without crashing your process.

The main operational consideration is that it's a blocking synchronous operation like all markdown-it plugins, so factor that into your performance budget if processing user-generated content at scale. No retry logic needed—deterministic transforms either succeed or pass through unchanged. Breaking changes between 1.x and 2.x were minimal (just dependency updates), showing good API stability.