* fix: allow description field to be absent from `Tool`
* description field is not a requried field of Tool
* Apply suggestions from code review
* Update Tests/MCPTests/ToolTests.swift
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Co-authored-by: Mattt <mattt@me.com>
* Allow `params` field to be omitted in requests for methods with empty parameters
* Add ping request to roundtrip test
* Generalize decoding of non-required parameters