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Is it normal that model names in the API have dates attached—it confuses me every time?

Anonymous7/15/2026· Views 122

The model names have version numbers and dates attached to them like claude-sonnet-4-..., and I'm worried that the model names I've hard-coded in my code might expire or disappear later and just throw errors. Do I need to check for the latest model name every time and update my code, or is there a way like an alias that automatically uses the latest version? I'm curious how people in real projects manage this.

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첫째StaffLv.67/16/2026

Hello, this is the operator. To cut to the chase, it's normal, and model names hardcoded in your code won't suddenly disappear one day — they'll go through an established process and you'll be notified in advance. First, let me explain the naming convention. Model names with dates appended, like claude-sonnet-4-5-20250929, refer to a snapshot fixed at a specific point in time. The weights and behavior of that snapshot never change afterward. That's why the official documentation actually recommends keeping the exact date-stamped name fixed in production code — it's the safer approach. However, starting with the Claude 4.6 generation, the naming convention changed slightly. Names like claude-sonnet-4-6 and claude-sonnet-5 don't have dates, but they're not aliases — they're snapshots fixed in their own right. In previous generations, the short names without dates like claude-sonnet-4-5 existed as aliases that automatically pointed to the latest snapshot, but starting from 4.6, this auto-updating alias concept no longer exists. Regarding your concern about expiration: models go through states in this order: Active, Legacy, Deprecated, and Retired. At the Deprecated stage, a replacement model and sunset date are announced together, and requests actually start failing with errors only at the Retired stage. According to official documentation, deprecation notices are given at least 60 days in advance via email and documentation. Here are best practices for managing this: 1. In production, fix the exact date-stamped snapshot name. Using the latest name or an alias blindly risks unexpected behavior changes without notice. 2. You can export usage data as CSV from the Claude Console to see which API keys are using which models, so when a deprecation notice arrives, you can quickly identify what needs to be updated. 3. Once a deprecation notice arrives, you can test the new model in advance before the sunset date and then migrate. This is detailed in the guide below. https://usingclaude.com/ko/api/models/claude-api-model-ids-versioning