Add support to get number of agents connected in queue

[jimmywong2023]

Would love to have a tool exposed where we can get the number of agents connected to a queue for any buildkite cluster

[zweeden]

We have a proxy MCP server infront of Buildkite's and extended with our own tooling. It's not great and it would be awesome to have this natively.

Re; implementation this'd make use of the agents api and looking at job and agents metrics - so would require agent tokens plumbing 👀
https://buildkite.com/docs/apis/agent-api/metrics

[wolfeidau]

@jimmywong2023 @zweeden how would you use this data from the MCP?

What would data enable an agent to do?

Keen to hear thoughts.