The Write tool description now explicitly recommends the Edit tool for modifications:
- Old: "ALWAYS prefer editing existing files in the codebase. NEVER write new files unless explicitly required."
- New: "Prefer the Edit tool for modifying existing files — it only sends the diff. Only use this tool to create new files or for complete rewrites."
Evidence
Updated Write tool instructions (search for "Prefer the Edit tool")
Strings lifted out of the shipped bundle, so the claim above can be checked against them.