I see the example interfaces for previous, and sadly defeated solvers is gone.
Leaving no trace of how that is supposed to work.
I stumbled across two relatively new attempts and wonders
if there is any code or docs on how to consider interfacing them.
Both are in Python so I expect that helps...

• Turnstile-Solver
• CAPTCHA solver

The 2nd being rather new so maybe some way off being useful....