Asking Dependabot to Rebase via MCP leads to malformed text in comment

[habereet]

Describe the bug

add_issue_comment mangles @mentions in comment bodies by inserting Unicode middle dot characters (·) between letters. This causes bot commands (e.g. Dependabot's @dependabot rebase) to silently fail because the mention is unrecognized.

Affected version

Version unknown; observed on June 16, 2026

Steps to reproduce the behavior

1. In Claude Code, ask Claude to post @dependabot rebase as a comment on a GitHub PR via the add_issue_comment MCP tool.
2. Observe the resulting comment body on GitHub.

Expected behavior

Comment body: @dependabot rebase

Actual behavior

Comment body: ·@·d·ependabot r·ebase

Additional context

The issue reproduces consistently on repeated calls with the same input. The mangled text prevents Dependabot from recognizing the command.