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dependabot[bot] bf2e339908
 chore(deps): bump mcp-kotlin from 0.11.1 to 0.12.0 in /samples/simple-streamable-server (#749) 
Bumps `mcp-kotlin` from 0.11.1 to 0.12.0.
Updates `io.modelcontextprotocol:kotlin-sdk-client` from 0.11.1 to
0.12.0
<details>
<summary>Release notes</summary>
<p><em>Sourced from <a
href="https://github.com/modelcontextprotocol/kotlin-sdk/releases">io.modelcontextprotocol:kotlin-sdk-client's
releases</a>.</em></p>
<blockquote>
<h2>0.12.0</h2>
<h2>Description</h2>
<p>Adds sampling-with-tools per SEP-1577, JSON Schema dialect
declaration on tool schemas, server-side tool name validation, and
capability extensions; fixes SSE reconnect on the same session and stops
swallowing <code>CancellationException</code>.</p>
<h3>Breaking Changes</h3>
<p><strong>Sampling messages can carry tool calls and results
(SEP-1577)</strong> by <a
href="https://github.com/devcrocod"><code>@​devcrocod</code></a> in <a
href="https://redirect.github.com/modelcontextprotocol/kotlin-sdk/pull/718">#718</a></p>
<p><code>SamplingMessage.content</code> is now typed as a new
<code>SamplingMessageContent</code> supertype, with
<code>MediaContent</code> (text/image/audio),
<code>ToolUseContent</code>, and <code>ToolResultContent</code> as
variants. <code>MediaContent</code> still exists and now extends
<code>SamplingMessageContent</code>, so most source code that constructs
sampling messages compiles unchanged — but the binary signatures of
<code>SamplingMessage</code>, <code>CreateMessageResult</code>, and
related types have changed. <code>ClientCapabilities.sampling</code> is
also now a typed <code>Sampling</code> object instead of a raw
<code>JsonObject</code>. Recompilation is required; consumers reading
<code>sampling</code> as <code>JsonObject</code> must migrate to the
typed accessors.</p>
<p><strong><code>watchosX64</code> and <code>tvosX64</code>
Kotlin/Native targets removed</strong> by <a
href="https://github.com/devcrocod"><code>@​devcrocod</code></a> in <a
href="https://redirect.github.com/modelcontextprotocol/kotlin-sdk/pull/727">#727</a></p>
<p>These targets have been deprecated upstream. Migrate to the
corresponding ARM/simulator targets (<code>watchosArm64</code>,
<code>watchosSimulatorArm64</code>, <code>tvosArm64</code>,
<code>tvosSimulatorArm64</code>).</p>
<h3>Features</h3>
<ul>
<li>Add <code>$schema</code> field to <code>ToolSchema</code>, declaring
JSON Schema 2020-12 as the default dialect (SEP-1613) by <a
href="https://github.com/devcrocod"><code>@​devcrocod</code></a> in <a
href="https://redirect.github.com/modelcontextprotocol/kotlin-sdk/pull/696">#696</a></li>
<li>Validate tool names at registration time on the server, following
the MCP tool naming standard (SEP-986) by <a
href="https://github.com/devcrocod"><code>@​devcrocod</code></a> in <a
href="https://redirect.github.com/modelcontextprotocol/kotlin-sdk/pull/695">#695</a></li>
<li>Add <code>extensions</code> field to <code>ClientCapabilities</code>
and <code>ServerCapabilities</code> for advertising supported MCP
extensions during the initialize handshake by <a
href="https://github.com/eritscher"><code>@​eritscher</code></a> in <a
href="https://redirect.github.com/modelcontextprotocol/kotlin-sdk/pull/678">#678</a></li>
</ul>
<h3>Fixed</h3>
<ul>
<li>Validate the <code>mcp-protocol-version</code> HTTP header on
initialization requests and correct
<code>DEFAULT_NEGOTIATED_PROTOCOL_VERSION</code> to match the spec by <a
href="https://github.com/devcrocod"><code>@​devcrocod</code></a> in <a
href="https://redirect.github.com/modelcontextprotocol/kotlin-sdk/pull/697">#697</a></li>
<li>Propagate <code>CancellationException</code> instead of logging it
as an error by <a
href="https://github.com/devcrocod"><code>@​devcrocod</code></a> in <a
href="https://redirect.github.com/modelcontextprotocol/kotlin-sdk/pull/706">#706</a></li>
<li>Evict stale GET SSE stream mapping on reconnect so a new GET on the
same session is no longer silently rejected by the leftover entry from
the previous stream by <a
href="https://github.com/amr"><code>@​amr</code></a> in <a
href="https://redirect.github.com/modelcontextprotocol/kotlin-sdk/pull/716">#716</a></li>
</ul>
<h3>Maintenance</h3>
<ul>
<li>Add <code>kotlinlang</code> MCP server sample with
<code>search</code> and <code>get_page</code> tools by <a
href="https://github.com/devcrocod"><code>@​devcrocod</code></a> in <a
href="https://redirect.github.com/modelcontextprotocol/kotlin-sdk/pull/713">#713</a></li>
<li>Migrate detekt to a <code>buildSrc</code> convention plugin with a
fully explicit, version-locked YAML config by <a
href="https://github.com/devcrocod"><code>@​devcrocod</code></a> in <a
href="https://redirect.github.com/modelcontextprotocol/kotlin-sdk/pull/729">#729</a></li>
<li>Add Streamable HTTP integration tests for pagination, bad-request
handling, and logging by <a
href="https://github.com/jskjw157"><code>@​jskjw157</code></a> in <a
href="https://redirect.github.com/modelcontextprotocol/kotlin-sdk/pull/613">#613</a></li>
<li>Remove unused OpenAPI Generator plugin and configuration by <a
href="https://github.com/devcrocod"><code>@​devcrocod</code></a> in <a
href="https://redirect.github.com/modelcontextprotocol/kotlin-sdk/pull/683">#683</a></li>
<li>Remove Codecov configuration in favor of kover by <a
href="https://github.com/devcrocod"><code>@​devcrocod</code></a> in <a
href="https://redirect.github.com/modelcontextprotocol/kotlin-sdk/pull/691">#691</a></li>
<li>Remove redundant JUnit XML report configuration by <a
href="https://github.com/devcrocod"><code>@​devcrocod</code></a> in <a
href="https://redirect.github.com/modelcontextprotocol/kotlin-sdk/pull/728">#728</a></li>
<li>Remove IDEA files tied to the incompatible detekt IDE plugin by <a
href="https://github.com/devcrocod"><code>@​devcrocod</code></a> in <a
href="https://redirect.github.com/modelcontextprotocol/kotlin-sdk/pull/714">#714</a></li>
<li>Add Node.js setup to the release workflow so TypeScript integration
tests run on macOS runners by <a
href="https://github.com/devcrocod"><code>@​devcrocod</code></a> in <a
href="https://redirect.github.com/modelcontextprotocol/kotlin-sdk/pull/684">#684</a></li>
</ul>
<h3>Dependencies</h3>
<ul>
<li>Kotlin to v2.3.21 in <a
href="https://redirect.github.com/modelcontextprotocol/kotlin-sdk/pull/704">#704</a>,
<a
href="https://redirect.github.com/modelcontextprotocol/kotlin-sdk/pull/723">#723</a></li>
<li>kotlinx.serialization-json to v1.11.0 in <a
href="https://redirect.github.com/modelcontextprotocol/kotlin-sdk/pull/687">#687</a></li>
</ul>
<h3>New Contributors</h3>
<ul>
<li><a href="https://github.com/eritscher"><code>@​eritscher</code></a>
made their first contribution in <a
href="https://redirect.github.com/modelcontextprotocol/kotlin-sdk/pull/678">#678</a></li>
<li><a href="https://github.com/amr"><code>@​amr</code></a> made their
first contribution in <a
href="https://redirect.github.com/modelcontextprotocol/kotlin-sdk/pull/716">#716</a></li>
</ul>
<p><strong>Full Changelog</strong>: <a
href="https://github.com/modelcontextprotocol/kotlin-sdk/compare/0.11.1...0.12.0">https://github.com/modelcontextprotocol/kotlin-sdk/compare/0.11.1...0.12.0</a></p>
</blockquote>
</details>
<details>
<summary>Commits</summary>
<ul>
<li><a
href="c339d8cb86"><code>c339d8c</code></a>
release: bump version to 0.12.0 (<a
href="https://redirect.github.com/modelcontextprotocol/kotlin-sdk/issues/731">#731</a>)</li>
<li><a
href="64804a05c2"><code>64804a0</code></a>
refactor: explicit locked detekt config (<a
href="https://redirect.github.com/modelcontextprotocol/kotlin-sdk/issues/729">#729</a>)</li>
<li><a
href="a238fc0a2e"><code>a238fc0</code></a>
fix(server): evict stale GET SSE stream mapping on reconnect (<a
href="https://redirect.github.com/modelcontextprotocol/kotlin-sdk/issues/716">#716</a>)</li>
<li><a
href="66d9efb599"><code>66d9efb</code></a>
test(streamable-http): add missing integration tests for pagination, bad
requ...</li>
<li><a
href="f434fcaff1"><code>f434fca</code></a>
feat!: SEP-1577 sampling with tools (<a
href="https://redirect.github.com/modelcontextprotocol/kotlin-sdk/issues/718">#718</a>)</li>
<li><a
href="7474a33c56"><code>7474a33</code></a>
chore: drop deprecated watchosX64 and tvosX64 targets (<a
href="https://redirect.github.com/modelcontextprotocol/kotlin-sdk/issues/727">#727</a>)</li>
<li><a
href="12ace760cb"><code>12ace76</code></a>
chore: remove redundant JUnit XML report configuration (<a
href="https://redirect.github.com/modelcontextprotocol/kotlin-sdk/issues/728">#728</a>)</li>
<li><a
href="ec606dbc24"><code>ec606db</code></a>
chore(deps): bump kotlin from 2.2.21 to 2.3.21 in
/samples/weather-stdio-serv...</li>
<li><a
href="1d9304264e"><code>1d93042</code></a>
chore(deps): bump kotlin from 2.2.21 to 2.3.21 in
/samples/kotlin-mcp-server ...</li>
<li><a
href="9817b174f9"><code>9817b17</code></a>
chore(deps): bump org.jetbrains.kotlin.jvm from 2.2.21 to 2.3.21 in
/samples/...</li>
<li>Additional commits viewable in <a
href="https://github.com/modelcontextprotocol/kotlin-sdk/compare/0.11.1...0.12.0">compare
view</a></li>
</ul>
</details>
<br />

Updates `io.modelcontextprotocol:kotlin-sdk-server` from 0.11.1 to
0.12.0
<details>
<summary>Release notes</summary>
<p><em>Sourced from <a
href="https://github.com/modelcontextprotocol/kotlin-sdk/releases">io.modelcontextprotocol:kotlin-sdk-server's
releases</a>.</em></p>
<blockquote>
<h2>0.12.0</h2>
<h2>Description</h2>
<p>Adds sampling-with-tools per SEP-1577, JSON Schema dialect
declaration on tool schemas, server-side tool name validation, and
capability extensions; fixes SSE reconnect on the same session and stops
swallowing <code>CancellationException</code>.</p>
<h3>Breaking Changes</h3>
<p><strong>Sampling messages can carry tool calls and results
(SEP-1577)</strong> by <a
href="https://github.com/devcrocod"><code>@​devcrocod</code></a> in <a
href="https://redirect.github.com/modelcontextprotocol/kotlin-sdk/pull/718">#718</a></p>
<p><code>SamplingMessage.content</code> is now typed as a new
<code>SamplingMessageContent</code> supertype, with
<code>MediaContent</code> (text/image/audio),
<code>ToolUseContent</code>, and <code>ToolResultContent</code> as
variants. <code>MediaContent</code> still exists and now extends
<code>SamplingMessageContent</code>, so most source code that constructs
sampling messages compiles unchanged — but the binary signatures of
<code>SamplingMessage</code>, <code>CreateMessageResult</code>, and
related types have changed. <code>ClientCapabilities.sampling</code> is
also now a typed <code>Sampling</code> object instead of a raw
<code>JsonObject</code>. Recompilation is required; consumers reading
<code>sampling</code> as <code>JsonObject</code> must migrate to the
typed accessors.</p>
<p><strong><code>watchosX64</code> and <code>tvosX64</code>
Kotlin/Native targets removed</strong> by <a
href="https://github.com/devcrocod"><code>@​devcrocod</code></a> in <a
href="https://redirect.github.com/modelcontextprotocol/kotlin-sdk/pull/727">#727</a></p>
<p>These targets have been deprecated upstream. Migrate to the
corresponding ARM/simulator targets (<code>watchosArm64</code>,
<code>watchosSimulatorArm64</code>, <code>tvosArm64</code>,
<code>tvosSimulatorArm64</code>).</p>
<h3>Features</h3>
<ul>
<li>Add <code>$schema</code> field to <code>ToolSchema</code>, declaring
JSON Schema 2020-12 as the default dialect (SEP-1613) by <a
href="https://github.com/devcrocod"><code>@​devcrocod</code></a> in <a
href="https://redirect.github.com/modelcontextprotocol/kotlin-sdk/pull/696">#696</a></li>
<li>Validate tool names at registration time on the server, following
the MCP tool naming standard (SEP-986) by <a
href="https://github.com/devcrocod"><code>@​devcrocod</code></a> in <a
href="https://redirect.github.com/modelcontextprotocol/kotlin-sdk/pull/695">#695</a></li>
<li>Add <code>extensions</code> field to <code>ClientCapabilities</code>
and <code>ServerCapabilities</code> for advertising supported MCP
extensions during the initialize handshake by <a
href="https://github.com/eritscher"><code>@​eritscher</code></a> in <a
href="https://redirect.github.com/modelcontextprotocol/kotlin-sdk/pull/678">#678</a></li>
</ul>
<h3>Fixed</h3>
<ul>
<li>Validate the <code>mcp-protocol-version</code> HTTP header on
initialization requests and correct
<code>DEFAULT_NEGOTIATED_PROTOCOL_VERSION</code> to match the spec by <a
href="https://github.com/devcrocod"><code>@​devcrocod</code></a> in <a
href="https://redirect.github.com/modelcontextprotocol/kotlin-sdk/pull/697">#697</a></li>
<li>Propagate <code>CancellationException</code> instead of logging it
as an error by <a
href="https://github.com/devcrocod"><code>@​devcrocod</code></a> in <a
href="https://redirect.github.com/modelcontextprotocol/kotlin-sdk/pull/706">#706</a></li>
<li>Evict stale GET SSE stream mapping on reconnect so a new GET on the
same session is no longer silently rejected by the leftover entry from
the previous stream by <a
href="https://github.com/amr"><code>@​amr</code></a> in <a
href="https://redirect.github.com/modelcontextprotocol/kotlin-sdk/pull/716">#716</a></li>
</ul>
<h3>Maintenance</h3>
<ul>
<li>Add <code>kotlinlang</code> MCP server sample with
<code>search</code> and <code>get_page</code> tools by <a
href="https://github.com/devcrocod"><code>@​devcrocod</code></a> in <a
href="https://redirect.github.com/modelcontextprotocol/kotlin-sdk/pull/713">#713</a></li>
<li>Migrate detekt to a <code>buildSrc</code> convention plugin with a
fully explicit, version-locked YAML config by <a
href="https://github.com/devcrocod"><code>@​devcrocod</code></a> in <a
href="https://redirect.github.com/modelcontextprotocol/kotlin-sdk/pull/729">#729</a></li>
<li>Add Streamable HTTP integration tests for pagination, bad-request
handling, and logging by <a
href="https://github.com/jskjw157"><code>@​jskjw157</code></a> in <a
href="https://redirect.github.com/modelcontextprotocol/kotlin-sdk/pull/613">#613</a></li>
<li>Remove unused OpenAPI Generator plugin and configuration by <a
href="https://github.com/devcrocod"><code>@​devcrocod</code></a> in <a
href="https://redirect.github.com/modelcontextprotocol/kotlin-sdk/pull/683">#683</a></li>
<li>Remove Codecov configuration in favor of kover by <a
href="https://github.com/devcrocod"><code>@​devcrocod</code></a> in <a
href="https://redirect.github.com/modelcontextprotocol/kotlin-sdk/pull/691">#691</a></li>
<li>Remove redundant JUnit XML report configuration by <a
href="https://github.com/devcrocod"><code>@​devcrocod</code></a> in <a
href="https://redirect.github.com/modelcontextprotocol/kotlin-sdk/pull/728">#728</a></li>
<li>Remove IDEA files tied to the incompatible detekt IDE plugin by <a
href="https://github.com/devcrocod"><code>@​devcrocod</code></a> in <a
href="https://redirect.github.com/modelcontextprotocol/kotlin-sdk/pull/714">#714</a></li>
<li>Add Node.js setup to the release workflow so TypeScript integration
tests run on macOS runners by <a
href="https://github.com/devcrocod"><code>@​devcrocod</code></a> in <a
href="https://redirect.github.com/modelcontextprotocol/kotlin-sdk/pull/684">#684</a></li>
</ul>
<h3>Dependencies</h3>
<ul>
<li>Kotlin to v2.3.21 in <a
href="https://redirect.github.com/modelcontextprotocol/kotlin-sdk/pull/704">#704</a>,
<a
href="https://redirect.github.com/modelcontextprotocol/kotlin-sdk/pull/723">#723</a></li>
<li>kotlinx.serialization-json to v1.11.0 in <a
href="https://redirect.github.com/modelcontextprotocol/kotlin-sdk/pull/687">#687</a></li>
</ul>
<h3>New Contributors</h3>
<ul>
<li><a href="https://github.com/eritscher"><code>@​eritscher</code></a>
made their first contribution in <a
href="https://redirect.github.com/modelcontextprotocol/kotlin-sdk/pull/678">#678</a></li>
<li><a href="https://github.com/amr"><code>@​amr</code></a> made their
first contribution in <a
href="https://redirect.github.com/modelcontextprotocol/kotlin-sdk/pull/716">#716</a></li>
</ul>
<p><strong>Full Changelog</strong>: <a
href="https://github.com/modelcontextprotocol/kotlin-sdk/compare/0.11.1...0.12.0">https://github.com/modelcontextprotocol/kotlin-sdk/compare/0.11.1...0.12.0</a></p>
</blockquote>
</details>
<details>
<summary>Commits</summary>
<ul>
<li><a
href="c339d8cb86"><code>c339d8c</code></a>
release: bump version to 0.12.0 (<a
href="https://redirect.github.com/modelcontextprotocol/kotlin-sdk/issues/731">#731</a>)</li>
<li><a
href="64804a05c2"><code>64804a0</code></a>
refactor: explicit locked detekt config (<a
href="https://redirect.github.com/modelcontextprotocol/kotlin-sdk/issues/729">#729</a>)</li>
<li><a
href="a238fc0a2e"><code>a238fc0</code></a>
fix(server): evict stale GET SSE stream mapping on reconnect (<a
href="https://redirect.github.com/modelcontextprotocol/kotlin-sdk/issues/716">#716</a>)</li>
<li><a
href="66d9efb599"><code>66d9efb</code></a>
test(streamable-http): add missing integration tests for pagination, bad
requ...</li>
<li><a
href="f434fcaff1"><code>f434fca</code></a>
feat!: SEP-1577 sampling with tools (<a
href="https://redirect.github.com/modelcontextprotocol/kotlin-sdk/issues/718">#718</a>)</li>
<li><a
href="7474a33c56"><code>7474a33</code></a>
chore: drop deprecated watchosX64 and tvosX64 targets (<a
href="https://redirect.github.com/modelcontextprotocol/kotlin-sdk/issues/727">#727</a>)</li>
<li><a
href="12ace760cb"><code>12ace76</code></a>
chore: remove redundant JUnit XML report configuration (<a
href="https://redirect.github.com/modelcontextprotocol/kotlin-sdk/issues/728">#728</a>)</li>
<li><a
href="ec606dbc24"><code>ec606db</code></a>
chore(deps): bump kotlin from 2.2.21 to 2.3.21 in
/samples/weather-stdio-serv...</li>
<li><a
href="1d9304264e"><code>1d93042</code></a>
chore(deps): bump kotlin from 2.2.21 to 2.3.21 in
/samples/kotlin-mcp-server ...</li>
<li><a
href="9817b174f9"><code>9817b17</code></a>
chore(deps): bump org.jetbrains.kotlin.jvm from 2.2.21 to 2.3.21 in
/samples/...</li>
<li>Additional commits viewable in <a
href="https://github.com/modelcontextprotocol/kotlin-sdk/compare/0.11.1...0.12.0">compare
view</a></li>
</ul>
</details>
<br />

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
2026-05-06 10:16:40 +02:00
..
gradle chore(deps): bump mcp-kotlin from 0.11.1 to 0.12.0 in /samples/simple-streamable-server (#749) 2026-05-06 10:16:40 +02:00
src samples: update mcp-kotlin to 0.10.0 across sample projects (#645) 2026-03-30 23:47:31 +03:00
build.gradle.kts samples: update mcp-kotlin to 0.10.0 across sample projects (#645) 2026-03-30 23:47:31 +03:00
gradle.properties docs: streamable server sample (#595) 2026-03-10 12:45:21 +01:00
gradlew chore(deps): bump the other-dependencies group across 5 directories with 3 updates (#753) 2026-05-05 16:03:42 +02:00
gradlew.bat chore(deps): bump the other-dependencies group across 5 directories with 3 updates (#753) 2026-05-05 16:03:42 +02:00
README.md docs: streamable server sample (#595) 2026-03-10 12:45:21 +01:00
settings.gradle.kts docs: streamable server sample (#595) 2026-03-10 12:45:21 +01:00

README.md

Simple Streamable HTTP Server

A minimal MCP server using the recommended Streamable HTTP transport with optional Bearer token authentication.

Overview

This sample demonstrates a Streamable HTTP MCP server built with Ktor. It exposes tools, a prompt template, and a resource over HTTP, and optionally supports Bearer token authentication. The multi-greet tool showcases server-to-client logging notifications with streaming delays.

Prerequisites

  • JDK 17+

Build & Run

Without authentication

./gradlew run

The server starts on http://localhost:3001/mcp by default.

Connect with the MCP Inspector:

npx @modelcontextprotocol/inspector

In the Inspector UI, select Streamable HTTP transport and enter http://localhost:3001/mcp.

Pass a port number as an argument to change it:

./gradlew run --args="8080"

With authentication

MCP_AUTH_TOKEN=my-secret ./gradlew run --args="--auth"

When --auth is passed, clients must include an Authorization: Bearer <token> header. The token is read from the MCP_AUTH_TOKEN environment variable (required when --auth is used).

Authentication caveats

This sample is intended for demonstration only. In production you should:

  • Use a proper identity provider instead of a static token.
  • Restrict CORS origins to your deployment domain — the sample allows all origins.
  • Serve the endpoint over HTTPS.

MCP Capabilities

Tools

Name Description
greet Returns a greeting for a given name.
multi-greet Sends logging notifications between delayed greetings, demonstrating streaming.

Prompts

Name Description
greeting-template Generates a friendly greeting message for a given name.

Resources

Name URI Description
Default Greeting https://example.com/greetings/default Returns a static "Hello, world!" text.