| Filename | Latest commit message | Latest commit date |
|---|---|---|
c1210009a5Bumps [io.modelcontextprotocol:kotlin-sdk-client](https://github.com/modelcontextprotocol/kotlin-sdk) 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=" |
||
| .. | ||
| gradle | ||
| src/main | ||
| build.gradle.kts | ||
| gradle.properties | ||
| gradlew | ||
| gradlew.bat | ||
| README.md | ||
| settings.gradle.kts | ||
Kotlin MCP Client
An interactive CLI client that connects to any MCP server over STDIO and pipes queries through Anthropic's Claude API.
Overview
This sample demonstrates a complete MCP client workflow: launching an MCP server as a subprocess, discovering its tools, converting them to Anthropic's tool format, and running an interactive chat loop where Claude can call server tools on behalf of the user.
Prerequisites
- JDK 17+
- An
ANTHROPIC_API_KEYenvironment variable set with a valid Anthropic API key - An MCP server script to connect to (
.js,.py, or.jar)
Build & Run
Run the client, passing the path to an MCP server:
# Connect to a JVM server
./gradlew run --args="path/to/server.jar"
# Connect to a Python server
./gradlew run --args="path/to/server.py"
# Connect to a Node.js server
./gradlew run --args="path/to/build/index.js"
Note
The client uses STDIO transport, so it launches the MCP server as a subprocess. Ensure the server script is executable and is a valid
.js,.py, or.jarfile.
MCP Capabilities
From the client perspective, this sample demonstrates:
- Tool discovery — lists tools from the connected server and converts them to Anthropic's tool format.
- Tool invocation — when Claude's response requests a tool call, the client invokes the corresponding MCP tool and feeds the result back into the conversation.