THU, JULY 30, 2026
Independent · In‑Depth · Practitioner‑Tested
Code Tools

Poolside Laguna S 2.1 vs Claude Fable 5 (2026): Open Weights at $0.10/M vs Closed API at $10/M

Best Open-Weight Coding Model vs Best Closed-Weight Coding Model — 100× Price Difference

🕐 5 min read 👁 15 views 📅 Jul 30, 2026

QUICK VERDICT — JULY 30, 2026

SWE-bench Pro: Fable 5 — 80.4% #1 vs Laguna 59.4%
Price: Laguna — $0.10/$0.20/M vs Fable 5 $10/$50/M (100× cheaper input)
Terminal-Bench 2.1: Laguna — 70.2% vs Fable 5 83.8% in Claude Code
Open weights: Laguna only — self-hostable on DGX Spark
Regulatory risk: Laguna — none. Fable 5 — had export control suspension (resolved).
Context: Both 1M tokens

Use Laguna S 2.1 for: High-volume coding workloads where the 59.4% SWE-bench Pro score is sufficient (roughly comparable to where GPT-4 was on SWE-bench in 2025), where self-hosting is valuable, and where 100× lower cost changes the economics of your use case fundamentally.

Use Fable 5 for: Production code changes where SWE-bench Pro 80.4% accuracy is specifically required and independently verified. If your engineering team has validated that the 21-point SWE-bench gap translates to meaningfully fewer bugs in your codebase — and it likely does — the $10/M premium is justified for critical production work.

Last updated July 30, 2026. Related: Laguna S 2.1 full review →

⚖ Our Verdict

Fable 5 wins on SWE-bench Pro (80.4% #1 vs Laguna 59.4%) and Terminal-Bench (83.8% vs 70.2%). Laguna wins on price (100× cheaper — $0.10 vs $10/M), open weights (self-hostable on DGX Spark), and no vendor lock-in. The 21-point SWE-bench gap is real and likely worth $9.90/M more for production code where accuracy is critical. For volume coding work where 59.4% is sufficient, Laguna's economics are compelling.