MarkTechPost ★ 106 5 min

AWS Strands Agents Team Releases Strands Harness: An Open-Source Agent Harness With 28% Lower Token Cost at Comparable Accuracy

Agentic AIAI AgentsFor DevsHarnessLanguage ModelLarge Language ModelOpen SourceSoftware EngineeringUncategorized

🔗 https://www.marktechpost.com/2026/09/21/aws-strands-agents-team-releases-strands-harness/

📌 AWS開源Strands Harness:同精度下token成本省28%

TL;DR:AWS開源通用Agent Harness「Strands harness」,實測顯示相近準確率下成本比同行低28%。

很多人在Claude Code或Codex裡驗證出一個Agent構想能跑,結果換成自己動手寫的迴圈重建後,效果卻大打折扣。AWS的Strands Agents團隊,這次盯上的正是這個落差。

🤔 從原型到生產環境的斷層

Strands harness是一個組裝完成、可直接使用的通用型Agent Harness,可在本地執行,也能部署到雲端服務供應商,提供Python與TypeScript版本,採Apache 2.0授權,一行程式碼即可啟動。根據MarkTechPost報導,團隊隨附的skills檔案能協助你的編碼Agent自動產生AWS、GCP、Azure、Cloudflare與Modal的部署設定。

所謂Harness,指的是圍繞模型運作的整套系統:迴圈邏輯、工具呼叫、上下文管理、記憶與錯誤恢復機制。Strands先前已透過Strands Harness SDK開放這些底層元件,這次的Strands harness則是把它們打包成一組可直接使用的預設組合。它被定位為通用型Agent,而非程式碼編輯專用的coding agent;呼叫create_harness()即可取得一個預先配置好的Agent實例。

📊 6項基準測試,同精度成本低28%

Strands Agents團隊使用Terminal-Bench創作者開發的評估框架Harbor,在Amazon EC2上進行分散式基準測試,分數為ALFWorld、ContextBench、GAIA、WebShop、τ²-bench與Terminal-Bench 2.1六項基準的平均值,成本則以每項任務的平均花費計算,對比對象包括Claude Code、Codex、oh-my-pi、OpenCode與DeepSeek Harness。

值得留意的是,DeepSeek Harness整體token效率其實是最高的,比Strands harness再便宜約14%,但每一項基準的分數都較低;圖表註腳說明,正是把DeepSeek Harness納入比較,才把整體節省幅度拉到28%這個數字。圖表中分數最高的點,是在Strands harness上執行Claude Opus 5,接近85%。最清楚的頭對頭比較,則是用Claude Fable 5跑Terminal-Bench 2.1,每個harness各跑89次試驗:相較Claude Code,Strands harness成本低77%,分數還高出7.9分;oh-my-pi以高54%的成本才打平69.7分的準確率;DeepSeek Harness雖然更便宜,分數卻落後10.2分。團隊也提到,另外還有兩個開源harness在成本與準確率上對Claude Code的表現也不錯。

💡 上下文管理才是關鍵變數

Strands harness預設就啟用了prompt caching與上下文管理,團隊表示上下文管理的預設規則,是同時驅動token效率與準確率提升的主要原因。這個結論也呼應了近期的HarnessTax研究:該研究比較了Claude Code、Codex CLI與Pi在7個模型上的表現,發現harness的選擇本身對成功率的影響很小,但同一個模型在不同harness下的成本卻可能相差達5倍。Strands研究團隊表示,針對這批基準測試的後續論文即將發布。

🎯 實務啟示

安裝方式很直接:pip install strands-harness或npm install @strands-agents/harness,並可用名稱直接指定模型,或指向本地的Ollama模型。搭配的Strands CLI(npm install @strands-agents/strands-cli)可以讓你用純文字描述原型化一個Agent,團隊的示範是要求Agent加入Playwright MCP伺服器並量測部落格文章的影片載入延遲,執行/export後就能輸出包含Playwright MCP設定的Python或TypeScript專案壓縮檔。由於Harness本身是一個函式庫依賴,筆電上原型化出來的Agent,理論上就是最終部署到生產環境的那一個,對於想避免「Demo能跑、重寫就掉分」問題的團隊,這個開發流程值得評估。

🔗 來源

#AWS #AgentHarness #OpenSource #LLMAgents #ContextManagement #ClaudeCode #TokenEfficiency #AIInfrastructure #AgentBenchmark #StrandsAgents

原始資料 MarkTechPost · 收集於 2026-09-22
來源原標題
AWS Strands Agents Team Releases Strands Harness: An Open-Source Agent Harness With 28% Lower Token Cost at Comparable Accuracy
作者
Asif Razzaq
原始標籤
Agentic AI · AI Agents · AI Shorts · Applications · Artificial Intelligence · Editors Pick · For Devs · Harness · Language Model · Large Language Model · New Releases · Open Source · Software Engineering · Staff · Tech News · Technology · Uncategorized
原始連結
https://www.marktechpost.com/2026/09/21/aws-strands-agents-team-releases-strands-harness/

摘要原文

Many developers find that an agent idea works inside Claude Code or Codex , then struggles once they rebuild it with their own loop. The Strands Agents team at AWS is targeting that gap with Strands harness , a fully assembled, general-purpose agent harness. It runs locally or deploys to a cloud provider, ships for Python and TypeScript under Apache 2.0, and starts with one line of code. The team reports 28% lower cost than other harnesses running the same Claude or GPT models across 6 benchmarks, with near-equal accuracy. Is it deployable? Yes. It runs locally, and a bundled skills file helps your coding agent generate deployment config for AWS, GCP, Azure, Cloudflare, and Modal. A harness is the system around the model: the loop, tools, context handling, memory, and recovery. Strands already exposed those building blocks through the Strands Harness SDK . Strands harness packages them into working defaults. It is built as a general-purpose agent, not a coding agent. Out of the box, create_harness() returns an agent that: The Strands Agents team ran distributed benchmarking on Amazon EC2 with Harbor , the evaluation framework from the Terminal-Bench creators. The score is the average across 6 benchmarks: ALFWorld , ContextBench, GAIA , WebShop , τ²-bench , and Terminal-Bench 2.1 . Cost is the average dollars per task. Rivals on the chart are Claude Code, Codex, oh-my-pi, OpenCode , and DeepSeek Harness. One important thing to note. DeepSeek Harness was the most token-efficient harness overall, running about 14% cheaper than Strands harness. It also scored lower on every benchmark. The chart footnote states that including it brought the overall savings figure down to 28%. The highest-scoring point on the chart is Claude Opus 5 on Strands harness, near 85%. The clearest head-to-head uses Claude Fable 5 on Terminal-Bench 2.1, with 89 trials per harness. Against Claude Code, Strands harness cost 77% less and scored 7.9 points higher. Oh-my-pi matched its 69.7 accuracy at 54% higher cost. DeepSeek Harness was cheaper still, but trailed by 10.2 points. The team also noted that 2 other open-source harnesses performed well on cost and accuracy against Claude Code. Strands harness ships defaults for prompt caching and context management. The team says context management largely drove both token efficiency and accuracy. 3 rules do the work: This matches recent independent research. The HarnessTax study compared Claude Code, Codex CLI, and Pi across 7 models. It found harness choice barely moved success rates, while the same model reached similar success at up to 5x the cost. The Strands researchers say a follow-up paper on their benchmarks is coming. Install with pip install strands-harness or npm install @strands-agents/harness . Pick a model by name, or point the harness at a local Ollama model: The Strands CLI ( npm install @strands-agents/strands-cli ) lets you prototype an agent in plain English. In the team’s demo, the agent was asked to add the Playwright MCP server and measure video load latency on a blog post. Running /export then produced the harness code, with the Playwright MCP included, as a Python or TypeScript zip. The CLI itself is built on Strands harness. Strands engineer Gautam Sirdeshmukh also used it to build a desktop app that starts Strands harness runs remotely. Customization goes deep. You can override any default, swap models, add tools, or replace components down to the Strands Harness SDK. Because the harness is a library dependency, the agent prototyped on a laptop is the same one embedded in production. Check out the Technical details , GitHub repo , PyPI package , and Strands Agents docs . The post AWS Strands Agents Team Releases Strands Harness: An Open-Source Agent Harness With 28% Lower Token Cost at Comparable Accuracy appeared first on MarkTechPost .

由 claude-code/sonnet 自動生成