--- title: DeepSeek Harness Just Changed AI Forever | daily.dev description: DeepSeek released an open source, MIT-licensed agent harness that quickly hit 150,000 GitHub stars, built on top of the existing Cordis plugin framework. Every... canonical: https://daily.dev/posts/deepseek-harness-just-changed-ai-forever-lclp0knx6 twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: DeepSeek Harness Just Changed AI Forever | daily.dev og:description: DeepSeek released an open source, MIT-licensed agent harness that quickly hit 150,000 GitHub stars, built on top of the existing Cordis plugin framework. Every... og:url: https://daily.dev/posts/deepseek-harness-just-changed-ai-forever-lclp0knx6 og:image: https://api.daily.dev/og/posts/lCLp0kNX6.png og:image:alt: DeepSeek Harness Just Changed AI Forever og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # DeepSeek Harness Just Changed AI Forever **[YouTube](https://daily.dev/sources/youtube)** · 5 min read · 1 upvotes · 1 comments ## Summary DeepSeek released an open source, MIT-licensed agent harness that quickly hit 150,000 GitHub stars, built on top of the existing Cordis plugin framework. Every capability in the harness (models, tools, skills, agents) is implemented as a swappable plugin, letting users bring their own model backends like Claude Sonnet 4.5, OpenAI, or Bedrock instead of DeepSeek's own models. Standout features include built-in append-only traceability logging every prompt, reasoning step, and tool call, plus a creator mode that lets users author new plugins purely through prompting, demoed by adding a playable dinosaur game to the desktop app. Alongside the harness, DeepSeek also shipped V4 Pro, a model priced well below Opus while reportedly matching GLM 5.2 on intelligence. Within days, the community built unofficial extras including a desktop app (11,000 stars), a TUI, web UI skins, and an awesome-list, none built by DeepSeek itself. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### What is the DeepSeek harness built on and how does its plugin system work? The DeepSeek harness is built on top of the Cordis kernel, a plugin framework that has existed on GitHub since 2022, described as a meta-framework for spatio-temporal compatibility. Every capability inside the harness - models, tools, skills, agents, sessions, and the API gateway - is implemented as a Cordis plugin, so any piece can be swapped, extended, or disabled entirely through configuration without touching the harness source code. _Developers weighing agent harness options can follow architecture breakdowns like this on daily.dev._ ### Can I use models other than DeepSeek's own models inside the DeepSeek harness? Yes, because the model itself is just a plugin in the DeepSeek harness, so it is not tied to DeepSeek's models. The documentation walks through adding Anthropic, OpenAI, Bedrock, or any OpenAI-compatible endpoint, and the official config example even includes Claude Sonnet 4.5 configured directly. _Teams comparing agent harnesses across model providers can track these details on daily.dev._ ### What does the traceability feature in the DeepSeek harness actually log? Traceability in the DeepSeek harness is an append-only log recording everything the model sees, including system prompts, reasoning steps, and tool calls, viewable as a full trajectory of the conversation. In the desktop app, clicking into a step shows token counts, such as one exchange using 187 tokens with 94 spent on reasoning, plus the model's full thinking output. _Engineers debugging agent behavior can keep an eye on tooling like this via daily.dev._ ## Similar posts on daily.dev - [DeepSeek API Docs](https://daily.dev/posts/deepseek-api-docs-mqussratb) · Hacker News · 0 upvotes · 0 comments --- Tags: [#open-source](https://daily.dev/tags/open-source), [#llm](https://daily.dev/tags/llm), [#ai-agents](https://daily.dev/tags/ai-agents), [#deepseek](https://daily.dev/tags/deepseek) [View this post on daily.dev](https://daily.dev/posts/deepseek-harness-just-changed-ai-forever-lclp0knx6) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"DeepSeek Harness Just Changed AI Forever","url":"https://daily.dev/posts/deepseek-harness-just-changed-ai-forever-lclp0knx6","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/deepseek-harness-just-changed-ai-forever-lclp0knx6"},"datePublished":"2026-08-25T07:06:28.701Z","dateModified":"2026-09-14T08:58:23.302Z","description":"DeepSeek released an open source, MIT-licensed agent harness that quickly hit 150,000 GitHub stars, built on top of the existing Cordis plugin framework. 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