ds-websearch-mcp

A simple MCP server for DeepSeek Search and Fetch.

Quick Start

Requires Node.js 24 or later and a DeepSeek API key.

Add the following to your MCP client configuration, replacing the API key. npx downloads and runs the package automatically:

{
  "mcpServers": {
    "ds-websearch-mcp": {
      "command": "npx",
      "args": ["-y", "ds-websearch-mcp"],
      "env": {
        "DEEPSEEK_API_KEY": "your-api-key"
      }
    }
  }
}

Restart your MCP client to load the search and fetch tools.

Codex

Run with your API key:

codex mcp add ds-websearch-mcp --env DEEPSEEK_API_KEY=your-api-key -- npx -y ds-websearch-mcp

Or add the following to ~/.codex/config.toml:

[mcp_servers.ds-websearch-mcp]
command = "npx"
args = ["-y", "ds-websearch-mcp"]

[mcp_servers.ds-websearch-mcp.env]
DEEPSEEK_API_KEY = "your-api-key"

Restart Codex to load the tools.

HTTP

Run the server on the loopback interface:

DEEPSEEK_API_KEY=your-api-key npx -y ds-websearch-mcp --transport http --port 3000

Connect an MCP client to http://127.0.0.1:3000/mcp.

Related MCP server: deepseek-web

Tools

search

Preserves upstream fields and ranking, including summaries, relevance scores, dates, and authority. Nonempty page content receives a pagination object. max_length applies to page content, not summaries or the total JSON response.

When a search returns page content, all pages that need caching are admitted as one batch. If the batch exceeds the configured entry or byte capacity, the tool returns an error and keeps existing cursors valid. Reduce count, increase max_length so more pages are returned completely, or increase the cache capacity.

DeepSeek currently documents 1–128 characters for query and ori_question, and 1–50 for count.

fetch

Supply exactly one of url and cursor. Returns url, title, content, and pagination:

{
  "returned_length": 5000,
  "total_length": 12400,
  "next_cursor": "opaque-cursor",
  "expires_at": "2026-10-20T12:15:00.000Z"
}

Pass next_cursor to fetch to continue. A null cursor means the end of the page. Unicode code points count as characters; surrogate pairs are never split. Cursor reads use the same saved snapshot, make no additional DeepSeek requests, and can be replayed. max_length can change between reads.

Only pages with remaining content are retained. Expiry is fixed when stored and is not extended by reading. Least recently read snapshots are evicted when the entry or byte limit is reached. Cursors expire with their snapshot and do not survive process restarts; an expired or evicted cursor returns a tool error asking the caller to fetch the URL again. Final-page reads keep the snapshot available until expiry or eviction for reliable retries.

A page larger than the cache capacity cannot be retained and returns an explicit error. Increase CACHE_MAX_BYTES or request a max_length large enough to return the full page. The byte limit accounts for retained text as UTF-16; it is not a limit on total process memory. HTTP requests share one process-local cache; cursors are signed and contain an unguessable snapshot identifier.

Configuration

Development

From a source checkout:

npm ci
npm run build
npm run check
npm test
npm pack --dry-run

License

Licensed under the GNU Affero General Public License v3.0 (AGPL-3.0-only).