Issue

While running concurrent Evals with the same name and the update property set to true, you notice that multiple Experiments are being created with a random suffix added to the end of the name.

Cause

When making truly concurrent calls to the Eval method in the SDK and/or initExperiment the backend attempts to resolve the Experiment name and collides with the concurrent requests, in this case it falls back to adding a random suffix to guarantee a unique name.

Resolution

Add an initialization step before concurrently running your Evals like:

 const experiment = initExperiment(projectName, {
    experiment: experimentName,
    description: `Eval: ${experimentName}`,
  });

This will allow the subsequent initExperiment and Eval calls to resolve to the correct name.