AGENTS.md

Repository expectations

Keep changes minimal and targeted.
Do not change public APIs, filenames, or build targets unless the task requires it.
Prefer fixing build and include-path issues over rewriting working logic.

Build requires data fetched from release of https://github.com/bareboat-necessities/oceanography-waves-lib (Check .github/workflows/build.yaml for instructions how to fetch simulation data file sim-data-files.zip)
Primary validation command: make all
After changing any .c, .cc, .cpp, .h, .hpp, .mk, or Makefile, run make all.
If the build fails, report the exact failing command and error.

This repo may run in environments where Eigen/Dense is not on the default compiler include path.
Prefer an existing vendored Eigen copy if the repo already contains one, such as third_party/eigen.
Otherwise preserve or use an include path equivalent to:
- CPPFLAGS += -I/usr/include/eigen3
- or make all CPPFLAGS+='-I/usr/include/eigen3'
Do not remove Eigen usage just to make the build pass.
If the environment itself is missing Eigen, note that Codex cloud setup must install libeigen3-dev.

Prefer small Makefile fixes that keep both local builds and Codex builds working.
Prefer a fallback pattern like:
- use vendored Eigen if present
- otherwise use /usr/include/eigen3

Before finishing: