# GPT-5.6 Sol on the Cotera agent benchmark

> The new flagship went 4/5 — beaten on schema discipline by its own cheaper siblings.

Source: https://cotera.co/benchmarks/models/azure-gpt-5.6-sol

---

OpenAI's GPT-5.6 Sol — the flagship tier of the July 2026 GPT-5.6 preview family, priced at GPT-5.5 parity ($5/$30 per 1M tokens). We ran it Cotera-hosted on Azure AI Foundry the day it landed.

**Score:** 4/5 benchmarks passed · **Cost across the matrix:** $0.697

## Strengths
- Fast for a flagship: the Marketing run finished in 17s and Sales in 17s — snappier than GPT-5.5 on the same tasks.
- Two tool calls and $0.036 on the Crunchbase brief. When the task is crisp, Sol does not wander.
- The Coding pass read the Stripe docs across 5 tool calls and produced the full HMAC + timing-safe-compare implementation with a docs citation.

## Watch-outs
- The one failure is the instructive kind: on CX it returned 4 complaints where the schema demands exactly 3. Over-delivering against a strict schema is still a failure in production.
- Most expensive of the three GPT-5.6 tiers at $0.70 for the matrix — and its two heaviest cells (Marketing $0.25, CX $0.24) were reasoning cost, not tool cost.
- It's a preview model: pricing and behavior may shift at GA, and Azure caps preview capacity. Re-verify before you standardize on it.