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+---
+id: 6ce2055a-b51b-45e4-8ff0-d34b385f7552
+type: decision
+title: "Issue-Worker Model: Sonnet over Opus for Cost-Efficient Autonomous PRs"
+tags: [claude-scheduled, issue-worker, model-selection, cost, decision, sonnet]
+importance: 0.5
+confidence: 0.8
+created: "2026-03-02T20:05:15.162290+00:00"
+updated: "2026-03-02T20:05:15.162290+00:00"
+---
+
+# Model Selection: Sonnet for issue-worker
+
+## Decision
+Use Sonnet (not Opus) for the autonomous issue-worker agent.
+
+## Rationale
+- Sonnet: ~$0.40-0.80/issue vs Opus: ~$2-4/issue
+- The $2 budget ceiling is sized for Sonnet
+- Multiple safety nets exist (tests, PR review by Cal, agent can skip)
+- Single-issue focused bug fixes are Sonnet's strength
+
+## How to Change
+One-line edit in `settings.json` to switch models. Revisit after reviewing PR quality over first week.
+
+## Trade-off
+Lower cost enables running on more issues; Opus reserved for tasks requiring deeper reasoning.