Claude Advisor Tool: Pair Haiku With Opus in Python

Run a Cheap Model, Call a Genius Only When It Counts

Here is the trade every agent builder knows. Run everything on a frontier model and the bill is brutal. Run everything on a small model and it makes confident, wrong decisions at the worst moments. The advisor tool on the Claude API splits the difference: a fast, cheap executor model does the bulk of the work and pulls in a stronger advisor model for a second opinion at the exact moments that decide whether a task succeeds.