A role model only seeded brand-new Sessions, so Workers created before a settings change kept their old route forever — the operator's complaint that the default model 'did not take effect'. On dispatch, ensure() now compares the durable selection or header of an existing Session against the configured role model and appends a model/selection event when they drift, leaving the deployment default alone. Seven unit cases cover drift, idempotence, effort, and precedence.
wandering1
DeepSeek Harness Team