
MODELS
by Arcee AI
Open reasoning model from Arcee AI for long-horizon agents, multi-turn tool calling, and reasoning tasks.
Trinity-Large-Thinking is Arcee AI’s reasoning-optimized Trinity-Large variant. Arcee documentation and the Hugging Face model card describe it as a 398B sparse MoE model with approximately 13B active parameters per token, built on Trinity-Large-Base. Arcee positions it for long-horizon agents, multi-turn tool calling, and agentic/tool-calling use cases, with agentic RL post-training. The Trinity product page lists Trinity Large Thinking as served on the Arcee API with 512K context and capabilities for tool use, structured outputs, and multi-turn conversations. Arcee’s announcement says it is available on the Arcee API with Hugging Face weights under Apache 2.0.
Use when evaluating an open reasoning model for long-horizon agent workflows. Use for multi-turn tool-calling experiments where agentic behavior and reasoning are primary requirements. Use when Apache 2.0-licensed model weights are important to your evaluation or deployment process. Compare it with other reasoning-optimized models for agentic workloads and structured-output workflows.
Last updated Jun 2, 2026