ClientModel: Provide API for indicating which service operation a request will be sent to

[annelo-msft]

One proposal is to add a string OperationName property on PipelineMessage. This issue tracks the work to determine the best approach to expose.

[joseharriaga]

This is needed to be able to support Azure OpenAI on top of OpenAI.

[annelo-msft]

@joseharriaga, would it be possible to provide a little more detail here, to help connect the dots across Azure OpenAI and OpenAI clients? Today, Azure clients don't use the PipelineMessage type in System.ClientModel, although that may or may not change with the Azure.Core 2.0 integration work stream. Would this API be called from within an Azure client, or somehow used to to integration across Azure/other clients?