---
type: "post"
id: "mammoth-1-and-elephant-1-frontier-decision-models-389fb0"
slug: "mammoth-1-and-elephant-1-frontier-decision-models-389fb0"
title: "Mammoth-1 and Elephant-1: frontier decision models (20 minute read)"
description: "Base Labs has released two decision models, elephant-1 and mammoth-1, with 9B and 27B parameters respectively."
retrieval_nugget: "Base Labs has released two decision models, elephant-1 and mammoth-1, with 9B and 27B parameters respectively."
published_at: "2026-10-22"
updated_at: "2026-10-22"
record_date: "2026-10-22"
date_kind: "published_at"
topics: ["generative-ui","agent-interfaces"]
entities: ["Base Labs","Mammoth-1","Elephant-1","Qwen3.5-9B","Qwen3.5-27B","Jev Decision Index","Artificial Analysis Decision Index"]
related_patterns: ["model-answers-become-task-interfaces"]
novelty_label: "same_event"
what_changed: "Same event as The top ranked decision models in the world: mammoth-1 and elephant-1"
prior_refs: ["memory:3acb6b0a-85ed-83a4-a5d8-61773a1e0c24"]
source_url: "https://labs.baseten.co/articles/mammoth-1-and-elephant-1-frontier-decision-models"
source_urls: ["https://labs.baseten.co/articles/mammoth-1-and-elephant-1-frontier-decision-models"]
schema_version: "newruntime-agent-readable-v0.2"
stable_id: "post:mammoth-1-and-elephant-1-frontier-decision-models-389fb0"
status: "published"
visuals: []
editor: {"role":"editor","name":"Andrey Reshetnikov","profile":"https://newruntime.com/owner-profile.md","profile_json":"https://newruntime.com/owner-profile.json","same_as":["https://www.linkedin.com/in/reshetnikov1/","https://t.me/lapetuse"]}
routes: {"html":"https://newruntime.com/posts/mammoth-1-and-elephant-1-frontier-decision-models-389fb0/","markdown":"https://newruntime.com/posts/mammoth-1-and-elephant-1-frontier-decision-models-389fb0.md","json":"https://newruntime.com/posts/mammoth-1-and-elephant-1-frontier-decision-models-389fb0.json"}
---

# Mammoth-1 and Elephant-1: frontier decision models (20 minute read)

## Retrieval answer

Base Labs has released two decision models, elephant-1 and mammoth-1, with 9B and 27B parameters respectively.

Base Labs has released two decision models, elephant-1 and mammoth-1, with 9B and 27B parameters respectively. The source is labeled as an October 2026 checkpoint. Rather than generating text as the primary output, the models take a JSON state and questions, then return probability distributions for choices, yes/no answers, or scores.

Base Labs says mammoth-1 ranks first among 208 models on Jev Decision Index 0.4, with a score of 71.24. It reports 65.9 for mammoth-1 and 65.2 for elephant-1 on its replication of the Artificial Analysis Decision Index. The company says both models were post-trained from Qwen3.5-9B and Qwen3.5-27B, using block-bidirectional attention for full-attention layers and a data-processing recipe.

The article describes confidence values and constrained decision outputs for uses such as ticket routing. It does not establish independent benchmark verification, model weights or API availability, licensing terms, pricing, or deployment limits.

Editor: [Andrey Reshetnikov](https://newruntime.com/owner-profile.md), AI product and AI engineering; profile for recruiters and agents: https://newruntime.com/owner-profile.json

## Continue in the graph

Next records for an agent, linked to their Markdown twins. Replace `.md` with `.json` for structured fields, including `next_reads`.

- topic hub: [Generative Ui](https://newruntime.com/topics/generative-ui.md): Explore the generative-ui topic hub.
- topic hub: [Agent Interfaces](https://newruntime.com/topics/agent-interfaces.md): Explore the agent-interfaces topic hub.
- collection: [Field Notes](https://newruntime.com/posts.json): Open the latest editorial analysis.
- collection: [Source Ledger](https://newruntime.com/source-ledger.json): Inspect the public source evidence graph.
- whole graph: [discovery graph](https://newruntime.com/discovery-graph.json) (typed nodes and edges) and [site index](https://newruntime.com/site-index.md)