Sub-line (character-level) staging — in scope? #4

Hello!

I came across your tool while researching partial staging tools for AI agent workflows.
The stable hunk IDs is an interesting design!
I was evaluating whether to build a custom tool for a need I have: staging at character granularity within a single diff line.

Would something like this be in scope for your project?
(ai input interface to be defined.. I have one for my unwritten custom tool, but it's too different from yours for other commands)

A few concrete examples:

Two independent changes on the same line:

-foo(old_arg, debug=True)
+foo(new_arg, debug=False)

I want to stage old_arg → new_arg only.
debug=True → False should stay unstaged.

Partial string change:

-const BASE_URL = "http://localhost:8080/api/v1"
+const BASE_URL = "https://api.prod.example.com/v2"

I want to stage http → https only.
The host and path refactor goes in a separate commit.

The initial approach I had in mind is straightforward.
Produce a hybrid + line that applies only the desired character-level change.
Wrap it in a valid hunk and pipe to git apply --cached.

👉 What do you think about this?