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…ansport Switch MCP HTTP transport from the deprecated streamablehttp_client() (mcp < 1.24.0) to the new streamable_http_client() API that accepts a pre-built httpx.AsyncClient. Changes vs the original PR #3391: - Separate try/except imports so mcp < 1.24.0 doesn't break (graceful fallback to deprecated API instead of losing HTTP MCP entirely) - Wrap httpx.AsyncClient in async-with for proper lifecycle management (the new SDK API explicitly skips closing caller-provided clients) - Match SDK's own create_mcp_http_client defaults: follow_redirects=True, Timeout(connect_timeout, read=300.0) - Keep deprecated code path as fallback for older SDK versions
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…ansport (NousResearch#3646) Switch MCP HTTP transport from the deprecated streamablehttp_client() (mcp < 1.24.0) to the new streamable_http_client() API that accepts a pre-built httpx.AsyncClient. Changes vs the original PR NousResearch#3391: - Separate try/except imports so mcp < 1.24.0 doesn't break (graceful fallback to deprecated API instead of losing HTTP MCP entirely) - Wrap httpx.AsyncClient in async-with for proper lifecycle management (the new SDK API explicitly skips closing caller-provided clients) - Match SDK's own create_mcp_http_client defaults: follow_redirects=True, Timeout(connect_timeout, read=300.0) - Keep deprecated code path as fallback for older SDK versions Co-authored-by: HenkDz <HenkDz@users.noreply.github.com>
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Summary
Switches MCP HTTP transport from the deprecated
streamablehttp_client()to the newstreamable_http_client()API introduced in mcp v1.24.0 (PR modelcontextprotocol/python-sdk#1177).Based on PR #3391 by @HenkDz (authorship preserved), with three fixes applied after deep-diving the SDK source:
Fix 1: Backward compat with older mcp versions
The original PR imported both functions in one line — breaks on mcp < 1.24.0 (our pin is
>=1.2.0). Now uses separate try/except imports with a_MCP_NEW_HTTPflag, gracefully falling back to the deprecated API on older SDK versions.Fix 2: httpx.AsyncClient lifecycle management
The new SDK API explicitly skips closing caller-provided clients (
if not client_provided: await stack.enter_async_context(client)in the SDK source). The original PR created the client but never closed it — connection pool leak. Now wrapped inasync with httpx.AsyncClient(...).Fix 3: Match SDK defaults exactly
Built the httpx client to match
create_mcp_http_client()defaults:follow_redirects=Truehttpx.Timeout(connect_timeout, read=300.0)(300s read timeout for SSE streams)Test plan
pytest tests/tools/test_mcp_tool.py tests/tools/test_mcp_oauth.py tests/tools/test_mcp_probe.py— 172 passed