# API
Open a `Service` with the managed Rust-library source root, Web-library source
and publication roots, and Rust-binary source and publication roots, plus a
crates.io token for Rust-library publication. The Web source and publication
roots must be disjoint. Call `execute` with a hidden session ID, one of the
exported tool names, a JSON argument value, and already-resolved ordered byte
objects. Non-call tools require an empty object list. Call `release` when the
session ends.
Rust-library and Rust-binary checks automatically format their disposable build
source. Layout that rustfmt can repair does not produce a tool failure.
`web_libraries_root()` returns the source root.
`web_publications_root()` returns the immutable Web publication root for the
integrating HTTP router.
`ToolExecution.text` is the exact model-facing result.
`ToolExecution.objects` contains exact ordered Rust-binary call output bytes
for the integrating server to store. It is empty for other tools.
`ToolExecution.snapshot` is present when a managed source box must be created or
updated. Rust-binary call text and objects are returned without parsing,
reformatting, wrapping, or storage.