Claude 3.5 Sonnet v2 vs Gemini 3.1 Pro Preview Custom Tools
How do these models stack up? Below is an expert side-by-side comparison of specifications, context window capacity, live pricing per million tokens, and standardized benchmark scores for Claude 3.5 Sonnet v2 and Gemini 3.1 Pro Preview Custom Tools.
Claude 3.5 Sonnet v2
Claude 3.5 Sonnet v2 is Anthropic's enhanced version of the breakthrough Claude 3.5 Sonnet, delivering significantly improved coding capabilities, longer context handling, and more reliable tool use at the same competitive pricing. It maintains the same 200K-token context window while achieving substantial gains in HumanEval, SWE-bench, and agentic task completion rates. Claude 3.5 Sonnet v2 remains widely used as a fallback model for teams that have standardized on the 3.5 architecture and prefer its consistent, well-characterized behavior for production deployments.
Gemini 3.1 Pro Preview Custom Tools
Gemini 3.1 Pro Preview Custom Tools is a variant of Gemini 3.1 Pro that improves tool selection behavior by preventing overuse of a general bash tool when more efficient third-party...
Technical Specifications
| Specification | Claude 3.5 Sonnet v2 | Gemini 3.1 Pro Preview Custom Tools |
|---|---|---|
| Provider | Anthropic | |
| Context Window | 200,000 tokens | 1,048,756 tokens |
| Agent Suitability | 92/100 | N/A |
| Time to First Token (TTFT) | 360 ms | N/A |
| Deployment Model | managed api | managed api |
| Production Stability | stable | beta |
| API Available | Yes | Yes |
| Released Date | 2025-02-15 | 2026-02-25 |
API Pricing Comparison
Input Price per Million Tokens
Claude 3.5 Sonnet v2
$3.00
Gemini 3.1 Pro Preview Custom Tools
$2.00
Output Price per Million Tokens
Claude 3.5 Sonnet v2
$15.00
Gemini 3.1 Pro Preview Custom Tools
$12.00
Want to test both models live?
Run side-by-side prompt prompts in our dynamic Sandbox. Check execution speeds, latency metrics, and compute actual costs in real-time.
Benchmark Performance Metrics
Scores show the raw performance percentages verified across key evaluation suites. Higher bars indicate superior accuracy and capability in that domain.
Claude 3.5 Sonnet v2 Quirks & Gotchas
- ▸Well-characterized production behavior — ideal for teams needing stability
- ▸Upgrade to Claude 4.6 Sonnet for 1M context and improved agentic performance
Gemini 3.1 Pro Preview Custom Tools Quirks & Gotchas
No developer gotchas reported.