When Opus 4.8 Is Justified
Multi-file code requiring cross-state coherence
Legal analysis beyond first-pass triage
Citation-critical document extraction
Financial table reconciliation
Tasks where silent failure is worse than expressed uncertainty
OCG LabTask-Domain Decision System
Reports
Decision Summary
Cross-domain model routing guidance converted into executive report panels.
When Sonnet 4.6 Is Default
Single-file debugging under ~300 lines
High-volume document summarization
JSON extraction from labeled inputs
Standard SQL repair
Customer support triage at scale
First-pass legal clause review
When GPT-5.5 Has Edge
Terminal-heavy agentic coding
CLI-integrated pipelines
Input-heavy batch tasks where cost is primary constraint
Mandatory Human Gates
Security code review final approval
Binding legal decisions
Financial outputs for reporting or audit
Any citation in published work