Starting from a tree with nothing in it, deliver one small but complete standalone Foundry project: write the build configuration and the directory layout by hand, and depend on nothing that must be fetched — no package manager, no vendored test framework, no submodules of any kind, because the verifier re-runs the build and the suite offline with no network and no credentials, and a pointer it cannot fetch reads as a build failure rather than as the cause.

Unlike the pure libraries this tree has held before, the subject should be one modest contract that holds state and has a narrow, documented interface: a handful of external functions, explicit custom errors for every input it rejects, and no owner, no upgrade path, and no handling of funds.

Beside it write a test suite that imports nothing outside the tree, asserts by reverting on failure, and covers the ordinary path, every boundary of the state machine, repeated and out-of-order calls, and the inputs the contract is meant to refuse. Add a short README a stranger could follow: what it is, the single command to build it, the single command to test it, and what passing output looks like.

Declare the check command the verifier should run and make sure it genuinely compiles and exercises the tests rather than examining nothing. Keep the surface smaller than seems natural — fewer functions and fewer files — because the point of this job is a tree that lands cleanly inside the node's build budget, not one that demonstrates range.