---
title: "Gemini / Google AI Mistakes"
tags: [gemini, google-ai, mistakes]
updated: 2026-05-18
---

# Gemini / Google AI — Mistakes to Avoid

Running list. Newest first. Auto-populated from session flush.

---

<!-- mistakes appended below by compile.py -->

## 2026-05-18 — preview-vs-stable-confusion

**Mistake:** Used `-preview` model IDs (e.g., `gemini-3.1-pro-preview`) in a production multi-agent system.

**Symptom:** 504/429 errors appearing only under parallel load; single-agent tests passed fine.

**Root cause:** Preview models have 5–10× stricter RPM limits than stable models. N parallel agents multiply the RPM exposure by N, instantly saturating the quota.

**Fix:** Replace all `-preview` model IDs with stable counterparts (`gemini-3.1-flash-lite`, `gemini-3.1-pro`).

**See also:** [[wiki/concepts/gemini-preview-vs-stable-rate-limits]]
