From c6e7337e7e220ea1927bb04a443992d9dda220eb Mon Sep 17 00:00:00 2001
From: awschmeder <awschmeder@lbl.gov>
Date: Tue, 3 Feb 2026 01:04:07 -0800
Subject: [PATCH] fix: add JSON tags to ElicitationCapabilities fields

The Form and URL fields in ElicitationCapabilities were missing JSON
struct tags, causing them to serialize as "Form" and "URL" (capitalized)
instead of the lowercase "form" and "url" required by the MCP protocol.

This caused initialization failures when clients advertised elicitation
capabilities, as servers would not recognize the incorrectly-cased keys.

Discovered via downstream issue: https://github.com/docker/cagent/issues/1574
---
 mcp/protocol.go | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/mcp/protocol.go b/mcp/protocol.go
index bea776f..2ac84de 100644
--- a/mcp/protocol.go
+++ b/mcp/protocol.go
@@ -988,8 +988,8 @@ type SamplingCapabilities struct{}
 //
 // If neither Form nor URL is set, the 'Form' capabilitiy is assumed.
 type ElicitationCapabilities struct {
-	Form *FormElicitationCapabilities
-	URL  *URLElicitationCapabilities
+	Form *FormElicitationCapabilities `json:"form,omitempty"`
+	URL  *URLElicitationCapabilities  `json:"url,omitempty"`
 }
 
 // FormElicitationCapabilities describes capabilities for form elicitation.