Claude Models
Model IDs and generations change. Choose by workload and confirm the available ID in the current official model documentation or account console.
#Family-level selection
The Chinese source uses Sonnet 4, Opus 4.1 and Haiku examples. Those are historical references rather than a current model catalog.
A balanced Sonnet-family candidate can be evaluated for ordinary writing, analysis and coding. A higher-capability Opus-family candidate may be useful for difficult reasoning or critical review. A lighter Haiku-family candidate may suit classification, extraction, preprocessing and simpler high-volume work.
#Measure rather than assume
Use a suitable default, escalate only where evaluation shows a quality benefit, and avoid sending every simple task to the most expensive option.
#Context is also a design choice
A larger context window does not mean every document should be attached. Split tasks or retrieve relevant material when possible; reserve long inputs for tasks that actually require them. Longer context can increase cost without improving focus.
#Model identifiers
Do not invent an API ID from a remembered marketing name or date. Use the documented identifier and plan for version changes.
