MCP client support for streamable HTTP

[alaa-eddine-k]

Summary by CodeRabbit

• New Features
  • Added support for the OpenAI Responses API.
  • Introduced GPT-5 family models with reasoning capabilities.
  • Enabled MCP Client support for Streamable HTTP transport with automatic fallback to SSE.
  • Improved connection error messaging for unsupported or misconfigured endpoints.
• Documentation
  • Updated changelog with v1.5.50 entry.
• Chores
  • Bumped core package version to 1.5.50.

[coderabbitai]

Caution

Review failed

The pull request is closed.

Walkthrough

Introduces v1.5.50 in core with changelog and package.json version bump. Refactors MCPClient to add a private connectMCP helper that first attempts Streamable HTTP transport, analyzes errors, and falls back to SSE transport when unsupported. Updates process flow to use the new connection method and adds logging.

Changes

Cohort / File(s)	Summary
Version bump and changelog packages/core/CHANGELOG, packages/core/package.json	Added v1.5.50 entry to changelog; bumped version from 1.5.46 to 1.5.50.
MCPClient connection flow packages/core/src/Components/MCPClient.class.ts	Added StreamableHTTPClientTransport support via new private method connectMCP(mcpUrl). Attempts streamable connect first; on unsupported cases falls back to SSE. Adds targeted error messaging for Accept header issues and logs connection outcomes. Updated process to use connectMCP.

Sequence Diagram(s)

sequenceDiagram
  autonumber
  participant Caller as Caller
  participant MCP as MCPClient
  participant Conn as connectMCP()
  participant SHTTP as StreamableHTTPClientTransport
  participant SSE as SSEClientTransport

  Caller->>MCP: process(mcpUrl)
  MCP->>Conn: connectMCP(mcpUrl)

  rect rgba(200,240,255,0.3)
    note over Conn,SHTTP: First attempt: Streamable HTTP
    Conn->>SHTTP: create/connect(mcpUrl)
    alt Streamable connected
      SHTTP-->>Conn: client
      Conn-->>MCP: { client, transport: "streamable" }
    else Error
      alt Accept header issue (406/Not Acceptable)
        Conn-->>MCP: throw explicit Accept header error
      else Unsupported for Streamable (404/405/ENOTFOUND/ECONNREFUSED/CORS)
        note over Conn,SSE: Fallback to SSE
        Conn->>SSE: create/connect(mcpUrl)
        SSE-->>Conn: client
        Conn-->>MCP: { client, transport: "sse" }
      else Other error
        Conn-->>MCP: rethrow original error
      end
    end
  end

  MCP-->>Caller: Proceed with connected client

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Estimated code review effort

🎯 3 (Moderate) | ⏱️ ~25 minutes

Poem

I thump my paws at v1.5.50’s gate,
Streamable first—what a snappy fate!
If headers fuss, I swiftly see,
Then hop to SSE, as light as can be.
Changelog carrots neatly stacked in a row—
Version blooms, onward we go! 🥕✨

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📥 Commits

Reviewing files that changed from the base of the PR and between a1bd8b8 and 327b59f.

📒 Files selected for processing (3)

• packages/core/CHANGELOG (1 hunks)
• packages/core/package.json (1 hunks)
• packages/core/src/Components/MCPClient.class.ts (3 hunks)

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