Hands-on with DeepSeek Harness Creation Mode: Generating Plugins with Natural Language

On the evening of November 2, DSH officially posted on social media saying "Your Harness, you define it," while also releasing DSH's Creation Mode, accompanied by a 1-minute-39-second video introducing Creation Mode.

This Creation Mode refers to letting users describe an idea in natural language, and the Agent writes the code, packages it, and installs it as a plugin that can be used directly in DSH.

DeepSeek officially released 7 demos, including a 3D Transformer visualization, a video editing desk with a multi-track timeline, a paper reader that preserves the original layout, a poster design workbench, a 3D landmark gallery, a theme plugin that can turn the entire interface into pixel style, and a usage dashboard that tracks tokens and costs.

DeepSeek also publicly released the Chinese and English prompts for these 7 demos; copy them in and select Creation Mode to reproduce them.

Strictly speaking, this mode is not something new. AI tech review blogger Rohan Paul said that DSH's Creation Mode has existed since August, and what was newly released on November 2 was the demo video and prompts.

In fact, as early as October 2, when Claude Code launched its Mods feature, Cui Tianyi posted to celebrate, while briefly introducing several major features of DSH's Creation Mode. For example, it can be used to change the interface, change the Agent loop mechanism, or add new orchestration methods.

So the significance of this release is more like taking a long-dormant capability and singling it out under the identity of "Creation Mode."

After testing, the community gave DSH's Creation Mode "overwhelmingly positive" reviews.

For example, Chinese-language blogger @NFT_Chen tested it that day with the official prompts and said all 3 plugins ran successfully: the 3D landmark gallery took about 21 minutes and cost $0.38, the poster workbench about 10 minutes and $0.1, and the session statistics about 11 minutes and $0.16. Before installation, a popup asks for permission; just click "Allow once."

However, some users said that Creation Mode still has room for improvement.

Currently, the operating logic of Creation Mode is that after the Agent finishes writing the code, it directly installs the plugin, so if the code written by the Agent has bugs, or if it is induced by malicious prompts to write something harmful to the computer, then it will cause damage to the user's computer.

This concern itself is necessary. What Creation Mode generates are executable plugins, and permissions and code security are inherently issues. DeepSeek itself also admits that some demos require multiple rounds of polishing, and that the entire project is still in the developer preview stage, with core plugins and APIs possibly subject to breaking changes.

Tech media outlet Startup Fortune believes that DeepSeek is amplifying the advantages of open source.

DeepSeek provides the skeleton of DSH, and users and the community decide what DSH looks like. DSH's characteristic is that everything is a plugin; its interface is a plugin, and its tools are also plugins. Rather than developing plugins for DSH, it would be better to simply let users define plugins themselves.

In this way, users will build plugins that are truly in demand for DeepSeek, and then DeepSeek can list these products through a plugin marketplace.

Through Creation Mode, DeepSeek has turned its open-source, inclusive market strategy into a developer ecosystem.

What Creation Mode reflects is also DeepSeek's current state: putting the power of definition into developers' hands.

Since October, DeepSeek has successively released multiple products. From the search service launched simultaneously with V4.1 Flash 1017, to open-sourcing its own in-production inference framework DeepInfer and the codec component deepseek-recipe. At the end of October, DSH also open-sourced the Super Agent prototype.

From the underlying model to the upper-layer Agent, DeepSeek is pushing almost every layer outward. But whether the "power of definition" is actually easy to use cannot be judged solely from official demos and other people's tests, so I also tried it myself and used Creation Mode to make two plugins.

Hands-on test

The prompt logic of Creation Mode is similar to the wish-style programming mentioned by DeepSeek in V4.1 Flash 1017. You do not need to describe exactly how the plugin should work; you only need to describe the final result you want.

But then again, the more detailed the description, the better the plugin's effect.

In DSH's official examples, Creation Mode can generate 3D previews and can also develop games. So I combined the two. After selecting Creation Mode, I followed the official examples and gave the following prompt.

"Create a DeepSeek Harness plugin with a left sidebar entry, make it an interactive 3D demo game, and use the whale girl image to make a 3D version of Mario."

Although the whale girl image is a bit painful to look at, the game quality is very good, and the controls feel very faithful to the FC version of Mario.

Counting from the input of the prompt, the entire development process took 1 hour and 14 minutes.

With this experience, the next time I use Creation Mode, I will specifically find some image assets for DeepSeek so that it can generate content that better matches mainstream aesthetics.

The second prompt is as follows.

This desktop pet can not only interact, but also give some interesting reactions based on my chats with DeepSeek. As shown in the video, after entering the prompt, the whale girl desktop pet will indicate that DeepSeek is thinking.

After DeepSeek gives an answer, the whale girl will also say, "This round is done. Want to pat me as a little break?"

But that's not all, because in addition to the basic interactions, DeepSeek also gives this whale girl three attributes: "Bond," "Mood," and "Vigor." These attributes can be raised through conversation and interaction; the higher they are, the happier the whale girl is, and the lower they are, the more she will show signs of fatigue—for example, she will indicate that she is tired and needs to rest.

The prompts for the two plugins together are only 100 characters. Wishful programming is still too authoritative.

However, during the generation process, you need to click "Allow" multiple times, and it is not like what the community said, where you can click once and then leave it alone. Even though I used DSH's experimental automatic review plugin, I still had to click "Allow" many times.

In addition, during the development of these two plugins, DSH's cache hit rate was 99%. Combined, the total cost of the two plugins was about 6 yuan.

Speaking of model-developed games, one has to mention Anthropic.

After the developer of "Needle in a Haystack Simulator" released a demo of the game, multiple developers used Claude to clone it and put it on shelves first, which turned the original "Needle in a Haystack Simulator" into the "imitation" instead. This developer even received extortion emails, and many studios therefore canceled public demos.

At the end of October, Claude sent a notice to users, the gist of which was: you can make original games, games of a certain genre, or games based on your own designs and assets, but do not replicate a specific existing game, even if you change the name or claim it is original.

Subsequently, Anthropic engineer Addy Osmani said the situation was true: when Opus 5.5 runs Claude Code, Anthropic adds these two sentences to the system prompt to prevent users from infringing intellectual property rights or violating usage rules when using Claude.

Back to Creation Mode itself: even though there are still minor issues such as cumbersome permission confirmations and unstable aesthetics in generated assets, its effect of lowering the barrier to plugin development is real.

Creation Mode happens to fill the gap between "little ideas in your head" and "tools." Whatever you think of, or whatever problem you find, just say it to DSH's Creation Mode and let it help you solve it.

One more point: so far, DSH has no official plugin marketplace. It only provides the underlying mechanism of "custom plugin index sources."

Users can enable the experimental custom plugin marketplace feature in settings, manually add third-party maintained index addresses, and browse, search, and one-click install plugins.

DeepSeek officially also has no unified official plugin distribution platform.

With Creation Mode, unofficial experts will inevitably produce frequently used hit plugins, which may in turn push DSH to open a plugin marketplace.

In any case, at least for ordinary users, being able to casually customize some exclusive little features for their own DSH is itself novel enough.

This article comes from the WeChat public account "Letter AI," author: Miao Zheng, authorized for publication by 36Kr.