# Amazon Strands Decider 2B ![Organization](https://img.shields.io/badge/Org-Amazon-FF9900) ![License](https://img.shields.io/badge/License-Apache%202.0-2da44e) ![Modality](https://img.shields.io/badge/Modality-Text-8957e5) ![Size](https://img.shields.io/badge/Params-2B-555) ![Released](https://img.shields.io/badge/Released-Oct%202026-blue) > **Quick answer:** Strands Decider 2B is a small (2B-parameter), Apache 2.0-licensed decision/classification model from Amazon, released October 1, 2026 as part of the Strands Agents framework. Rather than a general-purpose chat model, it is purpose-built for fast, cheap agent-routing decisions — selecting which tool, skill, or sub-agent should handle a given step in an agentic workflow. ## At a Glance **What it is:** A narrow, specialized decision-classifier model designed to sit inside an agent orchestration loop, not a general conversational LLM. **Why it matters:** Agentic systems built on frameworks like Strands Agents need frequent, low-latency routing decisions (which tool/skill to invoke next); a dedicated small model for this step is far cheaper and faster than calling a frontier LLM for routing on every step. **Known limitations:** It is not designed or benchmarked as a general-purpose LLM — standard knowledge/reasoning benchmarks (GPQA, HLE, SWE-bench, etc.) don't apply to its intended use case, and Amazon has not published results on Benchgen's existing benchmark suite. ## What Strands Decider 2B Is Strands Decider 2B is a 2-billion-parameter model released by Amazon on October 1, 2026 as part of the open-source Strands Agents framework. Its role is narrow and specific: given the current state of an agentic workflow, decide which tool, skill, or downstream sub-agent should execute next. This "decider" pattern lets a larger, more expensive frontier model focus on the substantive reasoning steps of a task while routing/dispatch decisions are handled by a much smaller, faster, and cheaper classifier. The model is released under the Apache 2.0 license and published on Hugging Face as `StrandsAgents/strands-decider-2B-hobson-v19`, reflecting Amazon's broader push to open-source components of the Strands Agents ecosystem alongside its proprietary offerings. Amazon reports Strands Decider 2B scoring approximately 72% accuracy (Brier score ≈0.35) on JevBench, an internal/early-stage routing-decision evaluation; this score has not been independently verified and JevBench is not yet a standardized cross-lab benchmark, so it is not included as a formal Benchgen leaderboard entry. ## Specifications | Field | Value | |---|---| | Organization | Amazon | | Parameters | 2B | | Hugging Face ID | `StrandsAgents/strands-decider-2B-hobson-v19` | | License | Apache 2.0 | | Modality | Text (decision/classification, not general chat) | | Release date | 2026-10-01 | | Framework | Strands Agents | ## Benchmark Notes Strands Decider 2B is not evaluated against general-purpose LLM benchmarks (GPQA, HLE, SWE-bench, etc.) in Amazon's announcement, since its intended use is narrow decision-routing rather than open-ended generation. Amazon's own reported figure — approximately 72% accuracy / 0.35 Brier score on JevBench, an internal routing-decision eval — is mentioned here for context only; JevBench does not yet have a Benchgen benchmark page, as it is not a publicly standardized, cross-lab-comparable benchmark. ## Frequently Asked Questions

What is Strands Decider 2B?

Strands Decider 2B is a 2-billion-parameter decision/classification model from Amazon, released October 1, 2026, designed to handle tool/skill-routing decisions inside agentic workflows built on the Strands Agents framework.

Is Strands Decider 2B open source?

Yes — it's released under the Apache 2.0 license and published on Hugging Face as `StrandsAgents/strands-decider-2B-hobson-v19`.

Does Strands Decider 2B score on standard LLM benchmarks like GPQA or HLE?

No — it's a narrow decision-classifier for agent routing, not a general-purpose LLM, so standard knowledge/reasoning benchmarks don't apply to its intended use case.

Strands Decider 2B — Evaluations

Evaluations