DonSeTch

The web, for AI agents. Fetch, search, crawl and screenshot from one local binary. Zero API keys, zero accounts.

v5: a new fetch engine. No browser in the fetch path: a wall is answered by the right client identity, the site's own challenge program run in-process, or the site's own public interface.

DonSeTch gives any AI agent full web research from a single local process: four tools, one Rust binary, no API keys, no accounts, nothing to configure. Fetching launches no browser (no Playwright, no Selenium, no headless Chrome): pages are read as a real client reads them, at curl's cost, and all four tool schemas fit in ~2k tokens.

Works with every MCP client (Claude Code, Cursor, OpenCode, Pi, Hermes) and as a standalone CLI.

Why it's different

Install

npm install -g donsetch

Optional Bright Data setup: SERP API and Web Unlocker guide. Use separate zones and add the exact dashboard names:

donsetch keys add brightdata "<token>::<SERP zone>"
donsetch keys add unlocker "<token>::<Web Unlocker zone>"
donsetch doctor --deep

Downloads the prebuilt binary for your platform from GitHub Releases with SHA256 verification. No build tools needed.

Verify the install: donsetch doctor (fast local sweep), doctor --deep (adds live browser and egress probes), doctor --fix (repairs mechanical problems), doctor --json (machine-readable, also prints ready-to-paste MCP registration blocks for your client).

If something goes wrong:

• pnpm or bun: the postinstall needs approval. pnpm approve-builds (or the bun equivalent), then reinstall. If scripts were blocked, npx donsetch runs the self-healing shim.
• --ignore-scripts: postinstall is intentionally skipped. Run node node_modules/donsetch/install.js, or use npx donsetch to download the binary when network access is available.
• System-wide installs: if the npm prefix is root-owned (for example /usr/local/lib/node_modules) and you run donsetch as a normal user, the package copy cannot be written there. donsetch then uses an existing binary from PATH or ~/.cargo/bin automatically; DONSETCH_BINARY=/path/to/donsetch points at one explicitly. To keep the package copy instead: npm config set prefix ~/.npm-global && npm install -g donsetch.
• Proxy: set HTTPS_PROXY (or https_proxy, HTTP_PROXY, http_proxy) to an HTTP CONNECT proxy.
• Release mirror: set DONSETCH_RELEASES_BASE to a mirror serving <tag>/<asset> paths, for example https://mirror.example/donsetch/releases.
• Windows: the installer needs tar, included since Windows 10 1803.
• musl/Alpine: published Linux binaries are glibc. Build from source on musl.
• First OCR or search run: it downloads the models (~24MB reranker, ~37MB OCR) and caches them forever.

Quickstart

1. As an MCP server (for agents)

{
  "mcpServers": {
    "donsetch": { "command": "donsetch", "args": ["mcp", "--supervised"] }
  }
}

--supervised is the crash-only daemon: a panic becomes a blip, the daemon restarts, the session survives. Without a global install, use "command": "npx", "args": ["donsetch", "mcp"].

Prefer HTTP over stdio? donsetch mcp --http --port 8765, clients connect to http://localhost:8765/mcp. Sessions, cancellation, /health, token auth (DONSETCH_HTTP_TOKEN) and per-request timeouts are documented in donsetch mcp --help.

Every client gets the [meta] fold by default: compact state and source evidence arrive together in content, including for unknown bridges and OpenCode's generic cli handshake. Raw MCP returns content blocks; some bridges join them into a string. Parse the leading [meta] JSON line, then read the source text. To get the split result instead (structuredContent kept) for clients DonSeTch does not recognize, set [mcp] text_only = false, or DONSETCH_MCP__TEXT_ONLY=false in the environment; details in the full README.

2. As a CLI (for humans and scripts)

donsetch fetch https://example.com/pricing --must-contain "free tier"
donsetch search "rust async patterns" --intent code
donsetch crawl https://docs.python.org --mode map --topic asyncio
donsetch screenshot https://example.com --out page.png
donsetch doctor
donsetch update

The 4 tools

MCP results default to self-contained text: leading [meta] JSON followed by source evidence, including for unknown client bridges. PNGs remain image blocks.

Every failure is structured: a stable code (wall.challenge, guard.ssrf, deadline.hit, network.dns…), an errorKind (permanent, transient, walled) and a next_action, so agents branch on codes instead of parsing prose.

Highlights

• Search without keys. Six keyless engines across four independent index families plus eight official verticals (GitHub, Wikipedia, HN, Semantic Scholar, arXiv, StackExchange, MDN, Google News), merged by consensus and re-ranked locally by an ONNX cross-encoder. 95.5% answer-in-snippet over 110 questions across 11 niches with no keys at all.
• PDFs done properly. A custom PDFium FFI, no Python subprocess. Tables and borders come from the rendered bitmap, text from the glyph stream, and the trust audit flags exactly the regions that need OCR.
• Crawl with manners. Per-host adaptive pacing that honors Retry-After and robots Crawl-delay, cross-process politeness so two crawls do not double a site's rate, near-duplicate detection, resume tokens that survive restarts, and honest stop reasons.
• Fetch that answers honestly. content_ok, thin, changed with section diffs, and must_contain says unverified instead of a false "not found" when part of a page was unread. No fake success.
• Walls named, not guessed. A bot wall names its vendor and what it asks for; a login wall is a declared wall.auth (fetch carries no session in v5; session support is planned).
• Works everywhere. Linux, macOS, Windows. npm, Homebrew, the Pi agent as a native extension, and the DeepSeek Harness as a first-class plugin.

Sponsors

DonSeTch is free and open source, and stays that way. Sponsorship pays for the time it takes to keep shipping.

Prepaid monthly, cancel anytime. One-time sponsorships are welcome at any amount.

Pricing goes up as the project grows. It is early now, so a Gold at $49/mo is near-zero investment for any company whose product touches agent web research. If your product is part of this space (proxy platforms, search infrastructure, BYO providers, anything a DonSeTch user would plug in), Gold goes one step further: fit natively inside DonSeTch and you get the placement plus an official integration shipped in the binary itself.

Email bhandaribishesh879@gmail.com to become a sponsor.

Docs

• Full README, install matrix, configuration reference: github.com/dondai44423/donsetch
• Every config knob with its origin: donsetch config show (or --markdown for the whole table)
• Changelog: CHANGELOG.md
• Issues and requests: github.com/dondai44423/donsetch/issues
• Contributing: CONTRIBUTING.md
• Pi agent: pi install npm:donsetch registers the tools as native pi tools and self-updates.
• DeepSeek Harness: dsh plugin --profile web add github:dondai44423/donsetch-dsh

License

AGPL-3.0. Copyright (c) 2026 Bishesh Bhandari.

If DonSeTch saves you time, star the repo or sponsor it.