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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
..
kotlin-mcp-client chore(deps): bump the other-dependencies group across 5 directories with 3 updates (#753) 2026-05-05 16:03:42 +02:00
kotlin-mcp-server chore(deps): bump the other-dependencies group across 5 directories with 3 updates (#753) 2026-05-05 16:03:42 +02:00
kotlinlang-mcp-server chore(deps): bump mcp-kotlin from 0.11.1 to 0.12.0 in /samples/kotlinlang-mcp-server (#745) 2026-05-06 07:50:37 +00:00
notebooks samples: update mcp-kotlin to 0.10.0 across sample projects (#645) 2026-03-30 23:47:31 +03:00
simple-streamable-server 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
weather-stdio-server chore(deps): bump the other-dependencies group across 5 directories with 3 updates (#753) 2026-05-05 16:03:42 +02:00
README.md sample: kotlinlang mcp server (#713) 2026-04-27 15:07:03 +02:00

README.md

Kotlin MCP SDK Samples

Runnable projects demonstrating MCP server and client implementations with the Kotlin MCP SDK. For background on the protocol itself, see the MCP documentation.

Overview

Sample Type Transport MCP Features
simple-streamable-server Server Streamable HTTP Tools, Resources, Prompts, Logging
kotlinlang-mcp-server Server Streamable HTTP Tools
kotlin-mcp-server Server STDIO, SSE Tools, Resources, Prompts
weather-stdio-server Server STDIO Tools
kotlin-mcp-client Client STDIO Tool discovery & invocation
notebooks Client (Notebook) Streamable HTTP Tool discovery & invocation

Getting Started

  • Building a server? Start with simple-streamable-server — it uses the recommended Streamable HTTP transport and covers tools, resources, prompts, and logging.
  • Building a client? Open the notebooks sample for a step-by-step walkthrough, or see kotlin-mcp-client for a full CLI client with Anthropic API integration.

Samples

Simple Streamable HTTP Server

A minimal Streamable HTTP server with optional Bearer token authentication. Demonstrates tools (greet, multi-greet), a prompt template, a resource, and server-to-client logging notifications. Read more →

Kotlinlang MCP Server

A Streamable HTTP server that exposes the official Kotlin documentation (kotlinlang.org) to LLM clients — full-text search via Algolia and page retrieval in markdown. Demonstrates wrapping a real external API in an MCP server with in-memory caching. Read more →

Kotlin MCP Server

A multi-transport server supporting STDIO, SSE (plain), and SSE (Ktor plugin). Useful for exploring different transport modes side by side. Read more →

Weather STDIO Server

A focused STDIO server that exposes weather forecast and alert tools backed by the weather.gov API. Includes Claude Desktop integration instructions. Read more →

Kotlin MCP Client

An interactive CLI client that connects to any MCP server over STDIO and routes queries through Anthropic's Claude API, bridging MCP tools with LLM conversations. Read more →

MCP Client Notebook

A Kotlin notebook that connects to a remote MCP server via Streamable HTTP and demonstrates ping, tool listing, and tool invocation — all in an interactive cell-by-cell format. Read more →