how to use Opus, Sonnet and Haiku 5.5 together in Claude Code (setup prompt included) > Opus advises > Sonnet builds > Haiku handles simpler tasks in parallel you can give each model a different role in Claude Code 1. Sonnet 5.5 handles the main task it coordinates the work, writes code and runs tests 2. Haiku 5.5 gathers the information subagents search files, look up documentation and handle smaller research tasks in parallel they report their findings back to Sonnet 3. Opus 5.5 provides guidance Claude Code’s advisor feature lets Sonnet consult Opus during the task Opus receives the conversation and returns guidance for planning, recurring errors and reviewing completed work start Sonnet 5.5 with Opus 5.5 as the advisor: --- claude --model claude-sonnet-5-5 --effort high --advisor claude-opus-5-5 then copy this prompt into Claude Code: Create a read-only research subagent in .claude/agents/ using model: claude-haiku-5-5. Its tasks are file discovery and documentation lookup. Return concise findings, file paths and sources to the main Sonnet session. Update the project’s CLAUDE .md: - Delegate independent research tasks to this subagent in parallel when useful. - Keep implementation and testing in the main session. - Request advisor consultation before complex changes, after recurring errors, and before completion. Preserve existing instructions. Show the proposed changes before applying them. ---- each advisor consultation adds usage, so use it where a review can help