Pagination in tools?

[justinmchase]

The sample tool call is very minimal and the tool api itself is basically completely open ended with no structure.

GetWeather Example

[Description("Gets the weather")]
string GetWeather() => Random.Shared.NextDouble() > 0.5 ? "It's sunny" : "It's raining";

var chatOptions = new ChatOptions
{
  Tools = [AIFunctionFactory.Create(GetWeather)]
};

Mcp Pagination?

The MCP protocol supports response formats that include pagination:
https://modelcontextprotocol.io/specification/2025-03-26/server/utilities/pagination

Is this relevant to tools? Is it handled lower down automatically?

Example

For example I've created a tool which returns an IAsyncEnumerable<T> result...

public async IAsyncEnumerable<ExampleDto> ListExamples()
{
  var tenantId = _context.Current.TenantId;

  _logger.LogInformation("Tool call: ListExamples");
  await foreach (var example in _repo.IterateExamples(tenantId))
  {
    yield return example.To().Dto();
  }
}

So the problem is that the set of Examples in this case is unbounded, there could be way more than the agent can reasonably handle (I think, right?).

Open Questions

• So what is the right way to handle unbounded sets in tool calls?
• Should we be responding with paged sets and returning Page<T> objects? Should I just stream it and assume that lower down it will handle it?
• Why are the tool function responses not more structured? Or is it and I'm just not finding the docs?