[Bug] Atlassian MCP: 403 Forbidden on transitionJiraIssue and addCommentToJiraIssue

Bug Description
▎ Bug: mcp__claude_ai_Atlassian__transitionJiraIssue and addCommentToJiraIssue return 403 from Claude Code while the identical operations succeed from claude.ai using the same Atlassian connector and account. ▎ ▎ Error: 403 Forbidden — "The app is not installed on this instance" ▎ ▎ Repro: ▎ 1. Configure Atlassian MCP connector in claude.ai (Atlassian account connected) ▎ 2. From claude.ai web — transitionJiraIssue succeeds ▎ 3. From Claude Code — same tool returns 403 ▎ ▎ What works from Claude Code: getJiraIssue, searchJiraIssuesUsingJql, createJiraIssue ▎ ▎ What fails from Claude Code: transitionJiraIssue, addCommentToJiraIssue ▎ ▎ Verified: Test ticket DEVOPS-11698 — all 5 write operations succeeded from claude.ai. Connector URL: https://mcp.atlassian.com/v1/mcp. Model: claude-sonnet-4-6[1m].

Environment Info

• Platform: win32
• Terminal: windows-terminal
• Version: 2.1.248
• Feedback ID: cbb08ab1-f47d-4612-9342-c5fbe1f18a2e

Errors

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