Claude Opus 5
Anthropic's most capable model.
The frontier model in the Claude 5 line, and the default choice when a task requires holding a lot of context and reasoning carefully across it. Where cheaper models produce plausible code that doesn't quite work, this is the tier that tends to actually finish.
Best for
Hard debugging, architecture decisions, and long autonomous agent runs.
Watch out for
Highest cost per token in the family. Don't spend it on boilerplate.
Using this and stuck anyway?
Knowing the tool isn't the same as finishing the project. If yours has stopped moving, we'll take a look at it.
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