Real-Time Edit Diff Streaming in Agents

Federal-Teaching2800 · reddit · 2026-07-15

The author shares two standout implementation details from building a code screen/CLI for the open-source agent Chimera:

1) Real-time diff display for every edit

Instead of waiting for the entire task round to finish, it directly reads the file content from the disk before and after every writefile / editfile / applypatch tool call.
It generates a unified diff from the before-and-after text, emitting it immediately if there are actual changes.
Because the tool loop is single-threaded, these before/after snapshots are precise.
This diff stream is optional; it won't read extra files if no sink is attached.

2) Accept / discard support strictly within git scope

After a task finishes, you can discard changes, but it only rolls back files that are visible to git and involved in the current run.
It filters tracked files using git ls-files, then runs git checkout; new files are handled with git clean.
This feature is only available inside a git repository and explicitly notes its inability to handle ignored/untrackable files.

Additional Info

The desktop version can be installed via pip install -U 'chimera-agent[desktop]'.
The author also shared repository and release links, asking the community how they typically handle edit-level diffs: real-time capture, snapshot diffs, or letting the tool output structured diffs natively.

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