fix: backport libghostty resize overflow fix

refs #465

1 files changed, 10 insertions, 0 deletions

diff --git a/AGENTS.md b/AGENTS.md
index b9fc4f50..c83a1d6d 100644
--- a/AGENTS.md
+++ b/AGENTS.md
@@ -49,6 +49,16 @@ Run `just check` before committing unless Can explicitly accepts narrower valida
 
 Unit tests live next to the code (`#[cfg(test)] mod tests`). New `AppState` or `Workspace` behavior should be testable with `AppState::test_new()` and `Workspace::test_new()` without PTYs.
 
+## Vendored libghostty-vt
+
+`vendor/libghostty-vt.vendor.json` records the upstream source commit currently vendored.
+
+Local patches on top of the vendored source must be tracked in `vendor/libghostty-vt.patches.md` and stored as patch files under `vendor/patches/libghostty-vt/`. Each entry should say why the patch exists, the Herdr issue, upstream PR/discussion, vendored base commit, touched files, verification, and the exact removal condition.
+
+When updating libghostty-vt, check every active patch in `vendor/libghostty-vt.patches.md`. If the new upstream commit contains the fix, remove the local patch and index entry, then rerun the listed verification. If not, reapply the patch on top of the new vendored source.
+
+`just check` runs maintenance tests that verify local libghostty-vt patch files are listed in the index and reverse-apply cleanly against the vendored tree. Do not leave a patch file untracked or an indexed patch unapplied.
+
 ## Docs
 
 Stable public docs live in `website/src/content/docs/`. They are the currently released herdr.dev docs. Do not document unreleased behavior there during normal feature or fix work.