fix(mcp): preserve non-ASCII text in JSON serialization#7256
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akios-ai wants to merge 1 commit intomicrosoft:mainfrom
Open
fix(mcp): preserve non-ASCII text in JSON serialization#7256akios-ai wants to merge 1 commit intomicrosoft:mainfrom
akios-ai wants to merge 1 commit intomicrosoft:mainfrom
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json.dumps calls in MCP tool return_value_as_string and StreamElicitor.elicit were missing ensure_ascii=False, causing non-ASCII characters (Japanese, Chinese, Korean, etc.) to be escaped as \uXXXX sequences. This degrades LLM performance when working with non-English text since models handle native characters better than unicode escapes. Fixes microsoft#6995
anandfresh
approved these changes
Feb 23, 2026
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json.dumps calls in MCP tool serialization were missing ensure_ascii=False, causing non-ASCII text (Japanese, CJK, etc.) to be escaped into \uXXXX sequences. This makes tool output unreadable when non-ASCII content is involved. Two call sites fixed in _base.py and _elicitation.py. Fixes #6995