Client Interaction in Model Context Protocol

Lessons in this section

1. Multi Round-Trip Requests

   How servers ask for input in 2026-07-28: input_required results, inputRequests and inputResponses, the client retry loop, requestState and how to protect it, round limits, and the Tasks extension.

2. Elicitation

   How MCP servers ask users for input: elicitation/create in form and URL mode, client capabilities, flat form schemas, host and server validation, accept, decline and cancel, and keeping secrets out of forms.

3. Roots, Sampling and Logging

   The three client features deprecated in 2026-07-28, why they were deprecated, the 12-month window, and migration paths: tool arguments and scopes, the host's model or your own model API, and stderr with OpenTelemetry.