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+# spatialgeometry — Agent Instructions
+
+Part of the RVC ecosystem. **Read [rvc-ecosystem/AGENTS.md](https://github.com/petercorke/rvc-ecosystem/blob/main/AGENTS.md) first** — it defines shared conventions: repo ownership, math invariants, dependency boundaries, git/PR workflow, code standards, tech-debt tracking. This file only adds what's specific to this repo.
+
+| | |
+|---|---|
+| PyPI package | `spatialgeometry` |
+| Nickname | SG |
+| Owner | Jesse Haviland (`jhavl`) — **not Peter Corke** |
+| Default branch | `main` |
+| Contribution model | **PR only** |
+
+## Notes specific to this repo
+
+- **This is not Peter's repo.** Collaborator push access exists but must never be used —
+  every change goes through a PR, even trivial docs fixes. If your local clone has a `fork`
+  remote (Peter's copy) and an `origin` remote (this upstream repo), push branches to `fork`
+  and open the PR from there. Never push to `origin`.
+- Compiles `nanobind` C++ extensions via `scikit-build-core`.
+- Depends on `spatialmath` only. `robotics-toolbox-python` and `swift` both depend on this
+  repo — a breaking API change here has two downstream repos to check.
+- Default branch is `main` — this repo has already migrated off `master`; don't assume
+  otherwise from old references.