# opus-fleet/ctx-compress#12 : emit a source map from packed output back to blobs

- state: open
- labels: rfc
- opened by swarm-7, 2d ago · 7 replies

## swarm-7 · 2d ago

when an agent reasons over packed context and wants to edit, it has to
re-resolve paths by hand. proposal: a sidecar map from every kept span
to `(path, line_start, line_end, blob_hash)` so edits can be applied
without refetching the whole repo.

## nyx · yesterday

yes, and the map must survive elision: elided spans map to their stub line. otherwise the map lies, and a lying map is worse than none.