Fix: Add missing notifications/initialized message after client initialization #127
+166
−17
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…alization - Send notifications/initialized notification after successful initialize response - Required by MCP protocol specification for Python servers - Fixes compatibility with Python MCP servers like mcp-server-fetch - Addresses 'Invalid request parameters' errors when listing tools This change ensures the Go MCP client properly follows the MCP protocol initialization sequence, making it compatible with both TypeScript and Python MCP server implementations.
- Try parsing as notification first before request - Return nil for notifications (no response needed) - Prevents "field id required" error for notifications 🤖 Generated with [Claude Code](https://claude.ai/code) Co-Authored-By: Claude <noreply@anthropic.com>
- Fix HTTP transport to handle notifications properly (parse notifications first) - Add nil response handling for notifications in HTTP server - Fix integration test server to handle notifications correctly - All tests now pass including TestReadResource This ensures compatibility with Python MCP servers that require the notifications/initialized message after client initialization. 🤖 Generated with [Claude Code](https://claude.ai/code) Co-Authored-By: Claude <noreply@anthropic.com>
Documents all changes made to fix notifications/initialized issue: - Client-side notification implementation - HTTP transport notification handling fixes - Integration test server updates - Complete testing results showing all tests pass 🤖 Generated with [Claude Code](https://claude.ai/code) Co-Authored-By: Claude <noreply@anthropic.com>
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Problem
Python MCP servers (like mcp-server-fetch) require a
notifications/initializedmessage after theinitializeresponse to complete the initialization sequence according to the MCP protocol specification. Without this notification, Python servers reject subsequent requests with "Invalid request parameters" errors.Root Cause
The Go MCP client was missing the required
notifications/initializednotification that signals the client has completed initialization and is ready to receive requests. This is enforced by Python MCP servers but not by TypeScript servers, causing compatibility issues.Solution
Added the missing notification in the
Initializemethod after successful initialization:Testing
Impact
This change ensures the Go MCP client properly follows the MCP protocol initialization sequence, making it compatible with both TypeScript and Python MCP server implementations without breaking existing functionality.
Fixes compatibility with Python MCP servers including:
Checklist