Field manual
BUILD FAST.
SHIP WITH SIGNAL.
Practical guides for choosing models, controlling inference costs, and putting faster agents into production.
Best Claude Model for Coding: A Task-by-Task Decision Guide
Sonnet 5 is the right default for most coding. Switch to Opus 5 when the task is genuinely hard, down to Haiku 4.5 for volume. Dated prices, plus a test you can run.
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