From d539c9697fc4e82c91e37ac40b8170395f98943a Mon Sep 17 00:00:00 2001
From: Artem Bukhonov <nerzhulart@gmail.com>
Date: Mon, 8 Dec 2025 17:10:39 +0100
Subject: [PATCH] Properly check content type. Should fix #450 (#451)

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## Motivation and Context
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## How Has This Been Tested?
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tested? -->

## Breaking Changes
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## Types of changes
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the boxes that apply: -->
- [x] Bug fix (non-breaking change which fixes an issue)
- [ ] New feature (non-breaking change which adds functionality)
- [ ] Breaking change (fix or feature that would cause existing
functionality to change)
- [ ] Documentation update

## Checklist
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that apply. -->
- [ ] I have read the [MCP
Documentation](https://modelcontextprotocol.io)
- [ ] My code follows the repository's style guidelines
- [ ] New and existing tests pass locally
- [ ] I have added appropriate error handling
- [ ] I have added or updated documentation as needed

## Additional context
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---
 .../kotlin/sdk/server/SSEServerTransport.kt                     | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kotlin-sdk-server/src/commonMain/kotlin/io/modelcontextprotocol/kotlin/sdk/server/SSEServerTransport.kt b/kotlin-sdk-server/src/commonMain/kotlin/io/modelcontextprotocol/kotlin/sdk/server/SSEServerTransport.kt
index c662464..1b33f39 100644
--- a/kotlin-sdk-server/src/commonMain/kotlin/io/modelcontextprotocol/kotlin/sdk/server/SSEServerTransport.kt
+++ b/kotlin-sdk-server/src/commonMain/kotlin/io/modelcontextprotocol/kotlin/sdk/server/SSEServerTransport.kt
@@ -80,7 +80,7 @@ public class SseServerTransport(private val endpoint: String, private val sessio
 
         val body = try {
             val ct = call.request.contentType()
-            if (ct != ContentType.Application.Json) {
+            if (!ct.match(ContentType.Application.Json)) {
                 error("Unsupported content-type: $ct")
             }