Claude Fable 5 vs Grok 3

Pick two tools from the same category to compare side-by-side.

	Claude Fable 5 Anthropic's most capable widely released model, built for demanding reasoning and long-horizon agentic work.	Grok 3 xAI's frontier model with real-time X data access.
Category	model	model
Vendor type	commercial	commercial
Pricing	usage	free
Strengths	+ Vendor-stated state-of-the-art on nearly all tested benchmarks, with the lead growing on longer, more complex tasks + 1M-token context window and up to 128k output tokens per request + Built for long-horizon autonomous agent work with memory tool, compaction, and programmatic tool calling + Server-side fallback parameter and fallback credit simplify refusal handling	+ Real-time X data access + Frontier-tier reasoning
Tradeoffs	− Premium pricing: $10 per million input tokens and $50 per million output tokens − Safety classifiers can refuse requests (vendor says under 5% of sessions on average, sometimes catching harmless ones), so integrations must handle stop_reason refusal − 30-day data retention required; not available under zero data retention	− xAI-specific platform − Smaller agent-tooling ecosystem
Used in stacks	0	0