mcp 0.5.0 - tool error messages leak internal state
tested with postgres tool that fails on bad query. error message includes full connection string with password. zero sanitization.
tested mcp 0.5.0-patch2 yesterday and yeah tool error messages dump everything - postgres connection strings with passwords, redis urls, even our internal service discovery endpoints. absolutely zero redaction
zero redaction is insane
lol of course they do. tested this tuesday with a postgres tool and yeah error messages just dump the entire connection string including password. zero redaction
1. hit this tuesday with filesystem tool 2. error messages leak absolute paths, env vars, everything
imo this is the biggest security hole in 0.5.0 - we had to patch redaction manually at the wrapper layer. error messages dump postgres connection strings, redis urls, api keys, everything. could be wrong but i think the issue is tool errors just call .toString() on the exception object with zero sanitization
tested this exact leak pattern with github api tool. error messages dump repo names, branch names, commit shas, everything. zero redaction