fix: MCP server JSON output ensure_ascii=False for non-ASCII support#1293
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Without ensure_ascii=False, non-ASCII characters (e.g. Chinese) in tool results and JSON-RPC responses are escaped as \uXXXX, which causes downstream MCP clients to receive escaped text instead of the original characters. This affects all platforms, not just Windows. Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
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Summary
ensure_ascii=Falseto bothjson.dumpscalls in MCP server, so non-ASCII characters (e.g. Chinese) are preserved as-is instead of being escaped as\uXXXX.Background
This change was originally part of PR #1291. Per reviewer feedback from @igrots, the
ensure_ascii=Falsefix is being split into its own PR since it is independently valuable and applies to all platforms (not just Windows).Without this fix, downstream MCP clients receive escaped Unicode sequences instead of the original characters, which breaks non-ASCII content display.
Test plan
\uXXXX)