Reasoning Quality
Both strong. Sonnet 4.5 excels on long-horizon agentic tasks and tool-heavy workflows. GPT-5 often leads on creative generation and broad-knowledge queries. Test on your actual workloads — generic benchmarks don’t predict your CRM-specific results.
Tool Use
Sonnet 4.5 particularly reliable for tool-call-heavy agents. Fewer wrong-tool picks, better argument formatting, cleaner retry behavior. For agent-heavy CRM use, this matters meaningfully.
Latency and Cost
Comparable in the same tier. Sonnet 4.5 slightly cheaper input tokens; GPT-5 sometimes faster on short outputs. At volume, both vendors negotiate — list prices rarely reflect enterprise reality.
Multi-Model Strategy
Best practice in 2026: don’t pick one. Route per task. Claude for agents, GPT-5 for content generation, smaller models for classification. Agentforce Vibes 2.0 normalizes this by supporting both as switchable defaults.