Set a Random Seed in OR-Tools Routing Solver

[Arun S]

Dear OR-Tools Team,

I am currently working with the OR-Tools Routing Solver (Python API) for a VRP with time windows and capacity constraints. I would like to evaluate the solver’s randomness by specifying a fixed random seed.

However, I am unable to find a supported way to set a random seed in the current version of OR-Tools. 

Could you please clarify:

1. Is there a supported way to set a random seed for the Routing Solver in the current Python API?

2. If not, is the routing search now fully deterministic given identical inputs?

3. What is the recommended approach for implementing multi-start behavior or controlled randomness in VRP using OR-Tools?

For context, I am using metaheuristics such as GUIDED_LOCAL_SEARCH.

Any guidance would be greatly appreciated.

Best regards,
Arun