dsh-free-search

Free web search provider for DeepSeek Harness — no API key, no cost.

A plugin that adds a DuckDuckGo-backed search provider to DeepSeek Harness (dsh), registered into the ctx.web seam. The built-in web_search tool picks it up automatically. Zero configuration, zero cost, zero keys.

English | 中文

Why

dsh ships a DeepSeek-official search provider by default, which requires a valid DEEPSEEK_API_KEY. If you:

• don't have (or don't want) a DeepSeek official API key,
• already use a gateway like opencode-go (which does not expose a web_search tool),

...then the built-in search always fails and the agent tells you "I can't access the internet."

This plugin fixes that with a free, keyless backend: DuckDuckGo's HTML search endpoint.

Features

• Zero cost — 4 free backends, no API key, no registration
• 4 engines to choose from: DuckDuckGo (html/lite), Bing, Mojeek
• Zero config — install and all engines register automatically
• Switch anytime — pick your engine via web.searchProvider
• Region support — optional region/market parameters per engine
• Clean integration — implements the official WebSearchProvider seam interface
• Composable — coexists with other providers (exa / perplexity / deepseek-official)

Engines

id	Engine	Notes
ddg	DuckDuckGo (html)	Default. Region param via region
ddg-lite	DuckDuckGo (lite)	Lighter markup, region not supported
bing	Bing	Market via bingMarket (default zh-CN)
mojeek	Mojeek	Privacy-focused, English-centric

All engines are enabled by default. Disable any with engines.<id>: false in the plugin config.

Install

git clone https://github.com/<your-username>/dsh-free-search.git
dsh plugin --profile web add /path/to/dsh-free-search

Then restart:

dsh web

Make it the default provider

Add this to your profile's cordis.patch.yml (e.g. ~/.dsh/profiles/web/cordis.patch.yml):

- id: web
  config:
    searchProvider: ddg   # or: ddg-lite | bing | mojeek

Alternatively set the environment variable DSH_WEB_SEARCH_PROVIDER=ddg.

Note for users behind the GFW / a proxy: DuckDuckGo is blocked in mainland China. Node.js fetch does not use the system proxy by default — set these environment variables for the dsh process (Node 24+):

export NODE_USE_ENV_PROXY=1
export HTTPS_PROXY=http://127.0.0.1:7897   # your proxy
export HTTP_PROXY=http://127.0.0.1:7897

Usage

Just ask the agent to search the web, e.g. "search for the latest DeepSeek Harness news". The web_search tool routes to the configured engine automatically.

Engine switcher tool (local UI)

Don't want to edit YAML by hand? The tools/ directory ships a tiny local switcher:

• tools/启动搜索引擎切换器.cmd (Windows) — double-click to start a local Node server (http://127.0.0.1:4789) and open the picker page in your browser.
• tools/switch-engine.html — the picker UI: shows the current engine, lets you pick a new one, and writes the config with one click.
• tools/server.mjs — the local server that reads/writes ~/.dsh/profiles/web/cordis.patch.yml.
• tools/switch-engine.ps1 — headless PowerShell alternative: powershell -File tools/switch-engine.ps1 -Engine bing.

After switching, restart dsh web for the change to take effect.

Note: dsh rc.6 does not expose third-party plugin config forms in its web Settings page (the settings allowlist is hard-coded), so this tool works around that with a local loopback server instead.

Compare with other providers

Provider	Cost	Key needed	Quality
ddg / ddg-lite / bing / mojeek (this plugin)	Free	No	OK
exa (official)	Paid	EXA_API_KEY	Good
perplexity (official)	Paid	PERPLEXITY_API_KEY	Good
deepseek-official (built-in)	Paid per token	DEEPSEEK_API_KEY	Best (native web search)

Switch anytime by changing web.searchProvider — no reinstall needed.

How it works

lib/index.js implements the WebSearchProvider interface (id / available() / search()), calls https://html.duckduckgo.com/html/?q=..., parses the result blocks, and returns normalized sources (url, title, snippet, publishedAt). The cordis.patch.yml inserts a loader entry so dsh mounts it into the ctx.web seam.

License

MIT