SearXNG MCP Server

Web Search

web_search

Read-onlyIdempotent

Search the web through a privacy-respecting SearXNG instance, with optional controls for language, categories, engines, and pagination.

Instructions

Perform a web search using a privacy-respecting SearXNG metasearch instance.

Input Schema

Name	Required	Description	Default
`query`	Yes	Search query to submit to SearXNG
`pageno`	No	Page number of results to fetch
`engines`	No	Optional list of specific search engines to use
`language`	No	Language code for search results (e.g. en-US)	en-US
`categories`	No	Optional list of categories to search in (e.g. general, news, science, files, images, videos, music, it, social_media)

Output Schema

Name	Required	Description	Default
No arguments

Schema Changelog

Changes observed during successful MCP inspections.

Changed13 schema fields changedv0.11.1May 22, 2026

addedInput schema / additionalProperties
```
Added value: +false
```

changedInput schema / properties / categories / description

Previous value: -"Categories to search in (e.g., 'general', 'images', 'news'). Default: null (all categories)."New value: +"Optional list of categories to search in (e.g. general, news, science, files, images, videos, music, it, social_media)"

changedInput schema / properties / engines / description

Previous value: -"Specific search engines to use. Default: null (all available engines)."New value: +"Optional list of specific search engines to use"

changedInput schema / properties / language / default
```
Previous value: -"en"New value: +"en-US"
```

changedInput schema / properties / language / description

Previous value: -"Language code for search results (e.g., 'en', 'de', 'fr'). Default: 'en'"New value: +"Language code for search results (e.g. en-US)"

removedInput schema / properties / max_results

Removed value: -{
-  "default": 10,
-  "description": "Maximum number of search results to return. Range: 1-50. Default: 10.",
-  "maximum": 50,
-  "minimum": 1,
-  "type": "integer"
-}

changedInput schema / properties / pageno / description

Previous value: -"Page number for results. Must be minimum 1. Default: 1."New value: +"Page number of results to fetch"

removedInput schema / properties / pageno / minimum
```
Removed value: -1
```
removedInput schema / properties / query / default
```
Removed value: -null
```

changedInput schema / properties / query / description

Previous value: -"Search query"New value: +"Search query to submit to SearXNG"

removedInput schema / properties / safesearch

Removed value: -{
-  "default": 1,
-  "description": "Safe search level: 0 (off), 1 (moderate), 2 (strict). Default: 1 (moderate).",
-  "type": "integer"
-}

removedInput schema / properties / time_range

Removed value: -{
-  "anyOf": [
-    {
-      "type": "string"
-    },
-    {
-      "type": "null"
-    }
-  ],
-  "default": null,
-  "description": "Time range for search results. Options: 'day', 'week', 'month', 'year'. Default: null (no time restriction)."
-}

addedInput schema / required
```
Added value: +[
+  "query"
+]
```

First observedv1.0.0Oct 16, 2025

TDQS

B3.2/5.0

Behavior3/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnlyHint=true and idempotentHint=true, so the safety profile is covered. The description adds only that the backing service is a privacy-respecting SearXNG instance – no mention of rate limits, auth, result volume, or how 'privacy-respecting' affects behavior, so the added value is modest.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

A single efficient sentence with the purpose front-loaded and no filler. It is perhaps overly terse for a tool with five parameters and multiple sibling alternatives, but nothing is wasted.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness3/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

With five parameters and an output schema present, the description covers the core action but omits anything about result shape, pagination limits, or how to choose engines/categories. Adequate but with clear gaps given the sibling set.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100%, so all five parameters (query, pageno, engines, language, categories) are documented in the schema itself. The description adds no syntax or format detail beyond that, so the baseline 3 applies.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb ('Perform a web search') and resource, plus the backend ('SearXNG metasearch instance'). It does not distinguish this from siblings like searxng_search_app or searxng_ingest_search, leaving the agent to infer which search variant to pick.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

No when-to-use guidance, no prerequisites, and no mention of when the sibling search tools (searxng_search_app, searxng_ingest_search) would be preferable. The agent must guess based on name alone.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

Deploy Server