[BUG] tooluniverse plugin MCPB fails to extract in Claude Code

[JiehoonKwak]

Environment

• Claude Code version: 2.1.5
• OS: macOS Darwin 25.2.0
• Plugin: tooluniverse@life-sciences v1.0.0

Description

The tooluniverse plugin fails to load - Claude Code cannot extract the MCPB file.

Error Message

Failed to extract MCPB
https://github.com/mims-harvard/ToolUniverse/releases/download/mcpb/tooluniverse.mcpb: 
Failed to read or unzip file: Failed to unzip file: undefined is not an object (evaluating 'T.length')

Steps to Reproduce

1. /plugin marketplace add anthropics/life-sciences
2. /plugin install tooluniverse@life-sciences
3. Restart Claude Code
4. Plugin shows error in /plugin menu

Verification

• MCPB file downloads successfully (3.2MB)
• Manual unzip -l tooluniverse.mcpb works - file is valid
• Other MCPB plugins from different marketplaces work fine
• Issue appears specific to this MCPB file's structure/compression

Questions

1. Is there something unique about how this MCPB was built?
2. Can the MCPB be regenerated with different compression settings?
3. Are other users experiencing the same issue?

Related

• Claude Code issue: [BUG] Plugin MCPB extraction fails for tooluniverse@life-sciences: 'undefined is not an object (evaluating T.length)' claude-code#17697
• MCPB source: https://github.com/mims-harvard/ToolUniverse/releases/tag/mcpb

[afonsoguerra]

I have that for the 10x genomics plugin. Works well in Claude Desktop, but fails in Claude Code with the same error.