Proposal: Explicitly supporting Long Running Tool Calls at protocol level

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This discussion is to brainstorm approaches, get community input, and track progress on designing support for long running or delayed tool calls in AG-UI.

As referenced in Issue #170, we need to explore and develop a proposal for supporting long running tool calls at the protocol level.

Context

The current AG-UI protocol needs enhancement to more explicitly support scenarios where:

• Tool calls may take significant time to complete
• Results may be delivered asynchronously through delayed responses
• User interfaces need to handle pending/in-progress states appropriately

Goals

• Brainstorm different architectural approaches
• Gather community feedback on proposed solutions
• Define clear requirements and use cases
• Develop a comprehensive proposal for implementation

How to Participate

Interested parties should:

• Follow and comment in this Discussion for ongoing conversation
• Share relevant use cases and requirements
• Provide feedback on proposed approaches

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Current state (as I see it) :

• Front end tool calls are already implicitly long running (i.e., based on current examples of HITL in the Dojo), so this should likely continue to be the default.
• Support for differentiating between long running and non-long running tool calls in agent frameworks is currently limited (i.e., it may just be ADK only - see Function Tool and Long Running Function Tool.)
• Given this, any additions to the protocol should likely be optional.