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Prevent stdout writes from corrupting MCP stdio transport#102

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BlazStojanovic wants to merge 2 commits intomainfrom
bs-fix-breaking-changes-v3
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Prevent stdout writes from corrupting MCP stdio transport#102
BlazStojanovic wants to merge 2 commits intomainfrom
bs-fix-breaking-changes-v3

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@BlazStojanovic
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@BlazStojanovic BlazStojanovic commented Feb 25, 2026

Fixes #101

The base ProgressLogger unconditionally writes OSC escape sequences to sys.stdout in __enter__/__exit__, which corrupts JSON-RPC messages on the stdio transport.

Introduce McpProgressLogger that overrides the context manager to preserve timing and log collection while skipping all stdout writes.

Other workarounds for kumoai>=2.15

  The base ProgressLogger unconditionally writes OSC escape sequences to
  sys.stdout in __enter__/__exit__, which corrupts JSON-RPC messages on
  the stdio transport. Introduce McpProgressLogger that overrides the
  context manager to preserve timing and log collection while skipping
  all stdout writes.
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Progress logger issues when using kumoai=2.15

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