fix: prevent dotenv from outputting to STDIO in MCP mode #151
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- Add { quiet: true } to dotenv.config() call
- Prevents dotenv log messages from interfering with MCP JSON-RPC communication
- Fixes "Unexpected token" JSON parsing errors in Claude Desktop
- No functional changes to environment variable loading behavior
Resolves STDIO pollution that breaks MCP protocol in STDIO transport mode.
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## [2.0.1](v2.0.0...v2.0.1) (2025-09-20) ### Bug Fixes * prevent dotenv from outputting to STDIO in MCP mode ([#151](#151)) ([9ec8c30](9ec8c30))
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🎉 This PR is included in version 2.0.1 🎉 The release is available on: Your semantic-release bot 📦🚀 |
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Problem
The
dotenv.config()call was outputting log messages to STDIO, which interfered with MCP's JSON-RPC communication in Claude Desktop. This caused "Unexpected token" JSON parsing errors when using STDIO transport mode.Error message:
Root cause:
dotenv was outputting messages like
[[email protected]] injecting env (0) from .envto STDIO, which broke the JSON-RPC protocol used by MCP servers.Solution
Added
{ quiet: true }option todotenv.config()call to suppress these log messages.Changes:
src/utils/config.util.tsTesting Results
Impact
This fix resolves STDIO interference for all Claude Desktop users without requiring any configuration changes on their part. Critical fix for MCP protocol compatibility.
Based on the fix originally proposed in mcp-server-atlassian-bitbucket#106 by @hansonkim.