Twisted Tongues has no public API. Today the way to work with a project programmatically is to save it to your computer — “Save to Computer…” inside any project, or see section 2.3 of the manual — and process the file. That file is in a documented, stable format, and this is where it is described:
Let us know if there's some other API you were hoping for: twisted-tongues-team@googlegroups.com.