Answer · Coding
What AI models does Windsurf use?
Windsurf runs on Cascade (Cognition), Claude (Anthropic), Claude Fable 5.1 (Anthropic), Claude Sonnet 4.5 (Anthropic), Devin (Cognition), Devin Local (Cognition), Fast (Cognition), Fusion (Cognition), Gemini (Google), GPT (OpenAI), GPT 5.2 Mini (OpenAI), GPT-5.2 (OpenAI), GPT-5.6 (OpenAI), GPT-6 Astra (OpenAI), Haiku (Anthropic), Kimi K2.5 (Moonshot AI), OpenAI frontier models (OpenAI), SWE 1.7 (Cognition), SWE-1.5 (Cognition), SWE-2 (Cognition) and Ultra (Cognition), and routes requests between them.
- Models used
- 21
- Primary model
- Claude Fable 5.1
- Public API
- Yes
- Last checked
- 2026-11-08
Model claims are labelled by how we know them: Cascade — unknown, Claude — inferred, Claude Fable 5.1 — disclosed, Claude Sonnet 4.5 — disclosed, Devin — inferred, Devin Local — unknown, Fast — unknown, Fusion — unknown, Gemini — inferred, GPT — inferred, GPT 5.2 Mini — disclosed, GPT-5.2 — disclosed, GPT-5.6 — disclosed, GPT-6 Astra — disclosed, Haiku — disclosed, Kimi K2.5 — disclosed, OpenAI frontier models — inferred, SWE 1.7 — disclosed, SWE-1.5 — disclosed, SWE-2 — disclosed and Ultra — unknown. "Disclosed" means the vendor says so in public; "inferred" means it was derived from documentation, headers or release notes.
Context window: Varies by model.
Other stack signals: vscode-extension.
Cite this answer
Tomorrow. “What AI models does Windsurf use?” Tomorrow AI & Emerging Tech Index, AlienSquad, updated 2026-11-08. https://tomorrow.aliensquad.ai/q/what-models-does-windsurf-use
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