Add client-level connect handshake to stdio transport#133
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a-akimov merged 1 commit intomodelcontextprotocol:mainfrom May 6, 2026
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Add client-level connect handshake to stdio transport#133a-akimov merged 1 commit intomodelcontextprotocol:mainfrom
a-akimov merged 1 commit intomodelcontextprotocol:mainfrom
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## Motivation and Context Follow-up to modelcontextprotocol/ruby-sdk#336 mcp gem 0.15.0 introduced an explicit `MCP::Client#connect` method for the stdio transport, aligning with the Python and TypeScript SDKs which require explicit handshake calls regardless of transport type: - Python SDK: `ClientSession.initialize()` https://github.com/modelcontextprotocol/python-sdk - TypeScript SDK: `Client.connect(transport)` https://github.com/modelcontextprotocol/typescript-sdk This sample is updated to call `@mcp_client.connect` explicitly after creating the client, demonstrating the recommended initialization pattern. The Gemfile constraint is bumped to `>= 0.15.0` to require the new API. ## How Has This Been Tested? Ran the sample against `weather-server-ruby` and confirmed the connection, tool listing, and chat loop continue to work as expected. ## Breaking Changes None. The change updates the sample to use the new explicit `connect` API, which was added as a non-breaking addition in mcp gem 0.15.0.
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## Motivation and Context Follow-up to modelcontextprotocol/ruby-sdk#336 and modelcontextprotocol/quickstart-resources#133. The Ruby example in `docs/docs/develop/build-client.mdx` constructed `MCP::Client` with a stdio transport and immediately called `client.tools`, relying on the implicit `initialize_session` that the stdio transport performed on the first request. ruby-sdk PR modelcontextprotocol#336 added `MCP::Client#connect` for the stdio transport so that the explicit `initialize` plus `notifications/initialized` handshake is exposed at the public API level, matching the Python SDK (`ClientSession.initialize()`) and the TypeScript SDK (`Client.connect(transport)`). The implicit-init path is preserved as a backwards-compatible shim, but new code is expected to call `connect` explicitly. This change updates the Ruby example so readers learn the explicit `@mcp_client.connect` pattern from the start, consistent with how the Python and TypeScript examples present the handshake. ## How Has This Been Tested? - Re-read the surrounding `connect_to_server` example in `docs/docs/develop/build-client.mdx` to confirm `@mcp_client.connect` fits naturally between the client construction and the subsequent `@mcp_client.tools` call. - Ran `npm run prep` to confirm there are no documentation warnings or errors introduced by the change. ## Breaking Changes None. This is a documentation-only change that adds a single explicit `connect` call to the Ruby client example. No schema, navigation, or runtime behavior is affected.
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## Motivation and Context Follow-up to modelcontextprotocol/ruby-sdk#336 and modelcontextprotocol/quickstart-resources#133. The Ruby example in `docs/docs/develop/build-client.mdx` constructed `MCP::Client` with a stdio transport and immediately called `client.tools`, relying on the implicit `initialize_session` that the stdio transport performed on the first request. ruby-sdk PR #336 added `MCP::Client#connect` for the stdio transport so that the explicit `initialize` plus `notifications/initialized` handshake is exposed at the public API level, matching the Python SDK (`ClientSession.initialize()`) and the TypeScript SDK (`Client.connect(transport)`). The implicit-init path is preserved as a backwards-compatible shim, but new code is expected to call `connect` explicitly. This change updates the Ruby example so readers learn the explicit `@mcp_client.connect` pattern from the start, consistent with how the Python and TypeScript examples present the handshake. ## How Has This Been Tested? - Re-read the surrounding `connect_to_server` example in `docs/docs/develop/build-client.mdx` to confirm `@mcp_client.connect` fits naturally between the client construction and the subsequent `@mcp_client.tools` call. - Ran `npm run prep` to confirm there are no documentation warnings or errors introduced by the change. ## Breaking Changes None. This is a documentation-only change that adds a single explicit `connect` call to the Ruby client example. No schema, navigation, or runtime behavior is affected.
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Motivation and Context
Follow-up to modelcontextprotocol/ruby-sdk#336
mcp gem 0.15.0 introduced an explicit
MCP::Client#connectmethod for the stdio transport, aligning with the Python and TypeScript SDKs which require explicit handshake calls regardless of transport type:ClientSession.initialize()https://github.com/modelcontextprotocol/python-sdkClient.connect(transport)https://github.com/modelcontextprotocol/typescript-sdkThis sample is updated to call
@mcp_client.connectexplicitly after creating the client, demonstrating the recommended initialization pattern. The Gemfile constraint is bumped to>= 0.15.0to require the new API.How Has This Been Tested?
Ran the sample against
weather-server-rubyand confirmed the connection, tool listing, and chat loop continue to work as expected.Breaking Changes
None. The change updates the sample to use the new explicit
connectAPI, which was added as a non-breaking addition in mcp gem 0.15.0.Types of changes
Checklist