Non-interactive Git Staging

Stage only the changes intended for the next commit. The index is shared state: preserve anything already staged unless the user explicitly asks to replace or unstage it.

Workflow

1. Inspect all three states:

   git status --short
   git diff --no-ext-diff
   git diff --cached --no-ext-diff
   

2. Derive the desired commit boundary from the user's request and the diff. Group by logical purpose rather than file count.

3. Choose the least complex safe operation:

   • complete file: git add -- <path>;
   • part of a file: construct a patch and apply it to the index;
   • ambiguous overlap with existing staged work: stop and clarify.

4. Verify both sides of the boundary:

   git diff --cached --no-ext-diff
   git diff --no-ext-diff
   git status --short
   

A successful git add or git apply is not sufficient evidence; the staged diff must contain the intended change and exclude unrelated work.

Partial staging

For selected hunks or lines, read Partial staging with index patches before constructing the patch. It contains the patch rules, validation sequence, and failure recovery. Do not use interactive git add -p in a non-interactive agent session.

Safety

• Use -- before paths that could be parsed as options.
• Do not discard working-tree content as part of staging.
• Do not use broad commands such as git add . when unrelated changes are present or the requested boundary is narrower.
• Keep temporary patches in a repository-approved ignored location and remove them when no longer needed.