Quick Start

Add to your MCP client configuration (e.g. claude_desktop_config.json):

{
  "mcpServers": {
    "searxng": {
      "command": "npx",
      "args": ["-y", "mcp-searxng"],
      "env": {
        "SEARXNG_URL": "YOUR_SEARXNG_INSTANCE_URL"
      }
    }
  }
}

Replace YOUR_SEARXNG_INSTANCE_URL with the URL of your SearXNG instance (e.g. https://searxng.example.com). You can also provide interchangeable replicas as a semicolon-separated list, e.g. https://one.example.com;https://two.example.com.

Features

• Web Search: General, news, and article queries with pagination, time-range/language/safe-search filters, relevance filtering (min_score), and formatted-text or raw-JSON output (response_format).
• Instance Failover & Fan-out: Configure interchangeable SearXNG replicas in SEARXNG_URL; searches fail over in order by default, or query all healthy replicas in parallel and merge results with SEARXNG_FANOUT.
• Direct Answers & Metadata: Text results surface SearXNG answers, corrections, suggestions, and infoboxes before the result list.
• Search Suggestions: Query autocomplete via SearXNG's /autocompleter endpoint.
• Instance Capability Discovery: Inspect configured categories, engines, defaults, locales, and plugins from /config.
• URL Content Reading: Content-type-aware Markdown conversion with pagination, section filtering, paragraph ranges, and heading extraction.
• Intelligent Caching: Both search results and URL content are cached in memory with configurable TTL and least-frequently-used (LFU) eviction, reducing redundant requests.
• SSRF Protection: web_url_read blocks private/internal URLs and redirects by default in all transport modes.
• HTTP Transport: Optional Streamable HTTP mode with opt-in hardening — bearer-token auth, CORS allowlist, and rate limiting.
• HTML Fallback: Optionally parse results from the HTML page for public instances that reject format=json.
• Lite Tools Mode: Minimal tool schemas for local models with small context windows.
• Proxy Support: Global or per-tool HTTP/HTTPS proxies for search and URL-reader traffic.

Why mcp-searxng?

How It Works

mcp-searxng is a standalone MCP server — a separate Node.js process that your AI assistant connects to for web search. It queries one SearXNG instance, or a semicolon-separated list of interchangeable SearXNG replicas, via the HTTP JSON API.

Not a SearXNG plugin: This project cannot be installed as a native SearXNG plugin. Point it at any existing SearXNG instance, or interchangeable replica list, by setting SEARXNG_URL.

AI Assistant (e.g. Claude)
        │  MCP protocol
        ▼
  mcp-searxng  (this project — Node.js process)
        │  HTTP JSON API  (SEARXNG_URL)
        ▼
  SearXNG instance(s)

Tools

• searxng_web_search

  • Execute web searches with pagination
  • Inputs:
    • query (string): The search query. This string is passed to external search services.
    • pageno (number, optional): Search page number, starts at 1 (default 1)
    • time_range (string, optional): Filter results by time range - one of: "day", "week", "month", "year" (default: none)
    • language (string, optional): Language code for results (e.g., "en", "fr", "de") or "all" (default: "all")
    • safesearch (string enum, optional): Safe search filter level, one of "0" (None), "1" (Moderate), or "2" (Strict). Legacy numeric values 0, 1, and 2 are still accepted for backward compatibility. (default: instance setting)
    • min_score (number, optional): Minimum relevance score from 0.0 to 1.0. Results below this score are filtered out.
    • num_results (number, optional): Maximum number of results to return, from 1 to 20. SEARXNG_MAX_RESULTS applies as an operator ceiling.
    • categories (string, optional): Comma-separated SearXNG categories (e.g. "news", "it,science"). Live /config capabilities are aggregated across reachable instances; prefer searxng_instance_info categories.common for consistent multi-instance results. Known values are trimmed and normalized case-insensitively; unknown values are forwarded trimmed so SearXNG can ignore or honor them. If /config is unavailable, values are forwarded as-is with a warning. If omitted, each instance uses its server-side default.
    • engines (string, optional): Comma-separated SearXNG engine names (e.g. "google,bing,ddg", "semantic scholar"). Live /config capabilities are aggregated across reachable instances; prefer searxng_instance_info engines.common.enabled for consistent multi-instance results. Known values are trimmed and normalized case-insensitively, including engines disabled by default; unknown values are forwarded trimmed so SearXNG can ignore or honor them. If /config is unavailable, values are forwarded as-is with a warning. If omitted, each instance uses its server-side default.
    • response_format (string, optional): Response format, either "text" for formatted agent-readable output or "json" for raw SearXNG JSON with filtered/sliced results. (default: "text")

• searxng_search_suggestions

  • Get autocomplete suggestions for refining search queries
  • Inputs:
    • query (string): Partial or complete query to autocomplete.
    • language (string, optional): Language code for suggestions (e.g., "en", "fr", "de") or "all" (default: "all")

• searxng_instance_info

  • Discover categories, engines, defaults, locales, and plugins exposed by all reachable configured SearXNG instances. The response reports common values present on every reachable instance and available values present on at least one reachable instance.
  • Inputs:
    • includeEngines (boolean, optional): Include enabled engine names in the response. (default: false)
    • includeDisabled (boolean, optional): Include disabled engine names when includeEngines is true. (default: false)
    • category (string, optional): Filter categories and engines to a single category name.
    • refresh (boolean, optional): Bypass the process cache and fetch fresh /config data. (default: false)

• web_url_read

  • Read URL content as markdown with content-type-aware handling and advanced extraction options
  • Supported readable content:
    • HTML (text/html, application/xhtml+xml) is converted to markdown
    • JSON (application/json, *+json) is pretty-printed in a fenced block
    • Plain text, YAML, TOML, XML, and other safe explicit text/* responses are returned as readable fenced text
    • Missing or generic content types are read under the existing size cap; non-binary bodies continue through the HTML-to-markdown path for compatibility
  • Binary, media, archive, PDF, and octet-stream downloads are intentionally rejected with a short hint instead of returning raw bytes
  • Inputs:
    • url (string): The URL to fetch and process
    • startChar (number, optional): Starting character position for content extraction (default: 0)
    • maxLength (number, optional): Maximum number of characters to return
    • section (string, optional): Extract content under a specific heading (searches for heading text)
    • paragraphRange (string, optional): Return specific paragraph ranges (e.g., '1-5', '3', '10-')
    • readHeadings (boolean, optional): Return only a list of headings instead of full content

Installation

npm install -g mcp-searxng

{
  "mcpServers": {
    "searxng": {
      "command": "mcp-searxng",
      "env": {
        "SEARXNG_URL": "YOUR_SEARXNG_INSTANCE_URL"
      }
    }
  }
}

docker pull isokoliuk/mcp-searxng:latest

{
  "mcpServers": {
    "searxng": {
      "command": "docker",
      "args": [
        "run", "-i", "--rm",
        "-e", "SEARXNG_URL",
        "isokoliuk/mcp-searxng:latest"
      ],
      "env": {
        "SEARXNG_URL": "YOUR_SEARXNG_INSTANCE_URL"
      }
    }
  }
}

docker build -t mcp-searxng:latest -f Dockerfile .

services:
  mcp-searxng:
    image: isokoliuk/mcp-searxng:latest
    stdin_open: true
    environment:
      - SEARXNG_URL=${SEARXNG_URL:?Set SEARXNG_URL in the environment}
      # Add optional variables as needed — see CONFIGURATION.md

{
  "mcpServers": {
    "searxng": {
      "command": "docker",
      "args": [
        "compose",
        "-f", "/absolute/path/to/docker-compose.yml",
        "run", "--rm", "-T", "mcp-searxng"
      ],
      "env": {
        "SEARXNG_URL": "YOUR_SEARXNG_INSTANCE_URL"
      }
    }
  }
}

services:
  mcp-searxng:
    ports:
      - "127.0.0.1:8080:8080"
    environment:
      - MCP_HTTP_PORT=8080
      - MCP_HTTP_HOST=0.0.0.0

MCP_HTTP_PORT=3000 SEARXNG_URL=http://localhost:8080 mcp-searxng

docker run --rm -p 3000:3000 \
  --add-host=host.docker.internal:host-gateway \
  -e MCP_HTTP_PORT=3000 -e MCP_HTTP_HOST=0.0.0.0 \
  -e SEARXNG_URL=http://host.docker.internal:8080 \
  isokoliuk/mcp-searxng:latest

{
  "mcpServers": {
    "searxng-http": {
      "type": "streamable-http",
      "url": "http://localhost:3000/mcp"
    }
  }
}

curl http://localhost:3000/health

Configuration

SEARXNG_URL is the only required variable — set it to your SearXNG instance URL (or a semicolon-separated list of interchangeable replicas). Everything else is optional.

See CONFIGURATION.md for the full environment variable reference, including authentication, failover/fan-out, caching, timeouts, proxies, TLS, HTTP transport, and hardening.

Troubleshooting

If HTTPS requests fail behind a TLS-inspecting corporate proxy with certificate errors, see TLS / Corporate CA.

403 Forbidden from SearXNG

Your SearXNG instance likely has JSON format disabled. Edit settings.yml (usually /etc/searxng/settings.yml):

search:
  formats:
    - html
    - json

Restart SearXNG (docker restart searxng) then verify:

curl 'http://localhost:8080/search?q=test&format=json'

You should receive a JSON response. If not, confirm the file is correctly mounted and YAML indentation is valid.

See also: SearXNG settings docs · discussion

Can't enable JSON? (HTML fallback)

If you must use a public instance you don't control and it rejects format=json (the 403 above), set the opt-in flag instead of editing the server:

"SEARXNG_HTML_FALLBACK": "true"

A search that gets a 403/404 or a non-JSON response is then retried automatically without format=json and parsed from the regular HTML results page.

• On success: you get normal results (title, URL, snippet). They are marked sourceFormat: "html" in JSON mode, and text mode adds the line "Note: Results parsed from SearXNG HTML fallback; metadata is limited." Relevance scores and engine names are not available from HTML.
• On failure: parsing is best-effort and varies by the instance's theme/version, so some results may be missed or sparse. If the HTML page itself also fails — still blocked, rate-limited (429), auth (401), or 5xx — the fallback attempt's error is surfaced, so the search never silently returns empty results. The fallback only triggers on 403/404/non-JSON, never on auth or network errors.

Enabling JSON on an instance you control (above) remains the recommended setup — the fallback is a compatibility aid, not a replacement.

Contributing

See CONTRIBUTING.md

License

MIT — see LICENSE for details.