dsh-webfetch

为 DeepSeek Harness 智能体装上「阅读器」：给定 URL，抓取网页并提取干净的 Markdown / 纯文本正文，附带链接清单与 RSS/Atom 订阅源解析。零运行时依赖，只读，不发送任何凭证。 English | 中文简介

A web page reader plugin for DeepSeek Harness (dsh). dsh agents can search, but until now they could not read the page behind a URL. dsh-webfetch closes that gap with four read-only tools and zero runtime dependencies (Node built-ins + global fetch only).

Tools

web_fetch

Fetch a web page and extract its readable content.

Returns { url, finalUrl, status, title, content, length, truncated, links? }.

user: what does the dsh README say about the architecture?
agent: web_fetch("https://github.com/deepseek-ai/deepseek-harness")
  → HTTP 200 — title: deepseek-harness
    ## DeepSeek Harness
    ..."everything is a plugin"...

web_links

Collect every link on a page with its visible label, resolved to absolute URLs, deduplicated, capped at limit (1–200, default 50). Useful for mapping what a page points to or crawling site structure.

web_feed

Read an RSS 2.0 or Atom feed and return its entries as a clean, LLM-friendly listing. Feed URLs are XML documents that web_fetch cannot extract from — web_feed parses them into structured entries instead.

Returns { url, finalUrl, status, feedTitle, entryCount, truncated, entries }, where each entry is { title, url, published?, author?, summary?, content? } with CDATA unwrapped, HTML entities decoded, markup stripped and relative links resolved against the feed URL.

user: what did the example blog post this week?
agent: web_feed("https://blog.example.com/feed.xml", maxItems: 5)
  → feed: Example Blog
    5 entries from https://blog.example.com/feed.xml
    1. First & foremost post — https://blog.example.com/posts/first
       published: Mon, 01 Jan 2024 10:00:00 GMT
       author: Alice
       Hello world — café & tea.

web_headers

Inspect the HTTP status, response headers and redirect chain of a URL without downloading the page body — the diagnostic companion to web_fetch: check status codes, content types, redirects, caching or security headers before (or instead of) pulling the content. Uses HEAD by default and falls back to GET automatically when the server answers 405/501; unlike web_fetch, any status is reported (404/500/… included) rather than thrown.

Returns { url, finalUrl, status, statusText, method, headers, redirects } where headers is the full response-header map (lower-cased keys) and redirects lists each hop as { url, status, location }.

user: is that download link still alive, and does it redirect?
agent: web_headers("https://example.com/downloads/latest")
  → HTTP 200 OK — HEAD https://example.com/downloads/latest
    redirect chain:
      1. 301 https://example.com/downloads/latest → https://cdn.example.com/releases/latest.zip
    final URL: https://cdn.example.com/releases/latest.zip
    12 header(s):
      content-type: application/zip
      content-length: 4821337
      ...

Install

dsh plugin --profile web add github:TYEclipse/dsh-webfetch
# or a pinned release:
dsh plugin --profile web add github:TYEclipse/dsh-webfetch#v0.3.0

Restart your agent session and the tools are available to the model.

Configuration

All settings are optional (defaults shown):

plugins:
  dsh-webfetch:
    timeoutMs: 10000        # per-request timeout (1000–60000)
    maxBytes: 1500000       # response size cap in bytes (10000–5000000)
    maxChars: 50000         # extracted content cap in chars (1000–200000)
    maxRedirects: 3         # redirect hops to follow (0–10)
    userAgent: "dsh-webfetch/0.3 (DeepSeek Harness plugin)"

Proxy support

Node's built-in fetch ignores HTTP_PROXY/HTTPS_PROXY, so on networks that require a proxy every request would fail. dsh-webfetch ships a zero-dependency http-proxy transport (CONNECT tunnelling for https, absolute-URI form for http, NO_PROXY matching with wildcard and IPv4 CIDR support) and uses it automatically:

• httpProxy / httpsProxy (default: HTTP_PROXY / HTTPS_PROXY env) — http://host:port URL; set to an empty string to disable.
• noProxy (default: NO_PROXY env) — comma-separated bypass list (exact hosts, .suffix, *.wildcard, IPv4 CIDRs, optional :port).

plugins:
  dsh-webfetch:
    httpsProxy: "http://127.0.0.1:7897"   # override env
    noProxy: "localhost,.internal,10.0.0.0/8"

Proxy credentials embedded in the proxy URL are sent as Proxy-Authorization: Basic (to the proxy only, never to the target).

Safety model

• http/https only — file:, ftp:, javascript: and friends are rejected.
• No credentials ever — URLs with embedded credentials are rejected; no cookies or authorization headers are attached; nothing is persisted.
• Bounded everything — hard timeout per request, redirect hop limit, response size cap, extracted-text cap. Oversized bodies are cut off and flagged (truncated: true), never buffered past the cap.
• Content-type gated — web_fetch/web_links parse only text/html and text/plain; web_feed additionally accepts application/rss+xml, application/atom+xml, application/xml and text/xml. Scripts, styles, comments and embedded content are stripped by the extractor/parser.
• Charset-aware — honours the Content-Type charset, falls back to XML declaration / <meta charset> sniffing, then UTF-8.

Development

pnpm install
pnpm build      # tsc
pnpm test       # vitest — 97 tests, fully offline (local fixture servers)
pnpm lint       # oxlint src test

License

MIT

中文简介

dsh-webfetch 是 DeepSeek Harness 的网页阅读插件：智能体拿到 URL 后可以直接抓取页面并提取干净的 Markdown 或纯文本（保留标题、链接、列表与代码块，剥离脚本/样式），web_links 可列出页面全部链接（解析为绝对地址、去重、限量），web_feed 可解析 RSS 2.0 / Atom 订阅源为条目清单（标题/链接/发布时间/作者/摘要/正文，处理 CDATA、HTML 实体与相对链接），web_headers 可用 HEAD 请求探测任意 URL 的 HTTP 状态码、响应头与重定向链而不下载正文（服务器不支持 HEAD 时自动回退 GET，非 2xx 状态照常报告）。零运行时依赖、只读、不发送凭证；http/https 协议限定、超时/重定向/体积/文本长度全部有上限，字符集自动识别（Content-Type → XML 声明/meta → UTF-8）；内置零依赖 http 代理支持（CONNECT 隧道 + NO_PROXY 白名单，自动读环境变量），在必须走代理的网络也能正常工作。与内置搜索互补：搜索给线索，webfetch 读正文，web_headers 读前诊断。