Code calling gpt-3.5-turbo, gpt-4, gpt-4-turbo, o1, o3-mini or o4-mini breaks on 2026-10-23

Symptom

Model ids that coding assistants still suggest by default stop being servedRequests fail for a model name that worked the week before

Cause

OpenAI retires the legacy GPT snapshots, including gpt-3.5-turbo, gpt-4, gpt-4-turbo, gpt-4o-2024-05-13, o1, o1-pro, o3-mini and o4-mini, on 2026-10-23. Older code and model defaults hardcode these names.

Fix

Replace each model with its listed substitute: gpt-3.5-turbo and o4-mini move to gpt-5.6-terra; gpt-4, gpt-4-turbo, gpt-4o-2024-05-13, o1 and o3-mini move to gpt-5.6-sol; o1-pro moves to gpt-5.6-sol with reasoning.mode pro; gpt-4.1-nano moves to gpt-5.6-luna. Keep the model id in configuration so the next retirement is a one line change.

ApplyCopy

const REPLACEMENT = { 'gpt-3.5-turbo': 'gpt-5.6-terra', 'gpt-4': 'gpt-5.6-sol', 'gpt-4-turbo': 'gpt-5.6-sol', 'gpt-4o-2024-05-13': 'gpt-5.6-sol', 'gpt-4.1-nano': 'gpt-5.6-luna', 'o1': 'gpt-5.6-sol', 'o1-pro': 'gpt-5.6-sol', // with reasoning: { mode: 'pro' } 'o3-mini': 'gpt-5.6-sol', 'o4-mini': 'gpt-5.6-terra', };

Affected

OpenAI API legacy snapshots, shutdown 2026-10-23; gpt-4o and gpt-4.1 snapshots follow on 2027-01-14

Sources

• https://developers.openai.com/api/docs/deprecations

Last verified 2026-10-15 · Confirmed by 0 builders