Originally published on NextFuture Claude Code /advisor Troubleshooting: 8 Errors and Fixes (May 2026) TL;DR: Eight errors I've hit running /advisor on real repos in April-May 2026, each with the exact message, the root cause, and the one-liner fix. Bookmark this for the next time your CLI screams at midnight. Quick diagnostic checklist Before grepping the table below, run these three: claude --version # 2.6+ required claude doctor # checks auth, MCP, hooks echo $ANTHROPIC_API_KEY | head -c 12 # sanity-check the key Enter fullscreen mode Exit fullscreen mode Most /advisor failures fall out of claude doctor immediately. If not, match symptoms below. For background on what /advisor actually does, see the Claude Code /advisor command deep-dive . 1. "model not found" Error: model "claude-3-5-opus" not found at AdvisorCommand.resolveModel ( advisor.ts:118 ) Enter fullscreen mode Exit fullscreen mode Cause: Stale config pinning a retired model alias. Anthropic deprecated claude-3-5-* in February 2026.…