Fixes MCP tools loading twice per session — a silent bug that surfaced as tool call errors with no obvious cause.
Change
1
Total Changes (vs Average)
0.1×
Version Type
Patch
Release Focus
Bug Fix
Days Since Prior Release
15
Release # This Month
#22 of 27
Bug Fix Ratio
100%
Post-Release Edits
—
Change Category
Ecosystem Impact
MCP has appeared in 4 of the last 10 releases — the most sustained attention of any non-General platform. This patch shores up tool call reliability during an ongoing extensibility investment period.
Key Themes
1MCP Double-Load Regression
May Help If You've Noticed
MCP tool calls fail or return errors even though the tool appears correctly configured
Your MCP tools seem to register or execute twice within the same session
Changes in Claude Code v0.2.63
Fixed1 change
•Fixed an issue where MCP tools were loaded twice, which caused tool call errors