MetaSearchMCP

Open-source metasearch backend for MCP, AI agents, and LLM workflows.

MetaSearchMCP aggregates results from multiple search providers, normalizes them into a stable JSON schema, and exposes both an HTTP API and an MCP server for agent tooling.

Positioning

• MCP-first metasearch backend
• Structured search API for AI pipelines
• Multi-provider search orchestration with deduplication and fallback
• Python FastAPI alternative to browser-first metasearch projects

Why It Exists

Most search aggregators are designed around browser UX: HTML pages, pagination, and interactive result cards. Agents and LLM workflows need a different contract: predictable JSON, stable field names, partial-failure tolerance, and provider-level execution metadata.

MetaSearchMCP is built for that machine-consumable workflow. The design is centered on search orchestration, normalized contracts, and MCP integration.

Core Features

• Concurrent multi-provider aggregation
• Unified result schema for web, academic, developer, and knowledge sources
• Provider-level timeout isolation and partial-failure handling
• Result deduplication across engines
• Provider selection by explicit names or semantic tags such as web, academic, code, and google
• Final result caps for agent-friendly payload sizing
• HTTP API with OpenAPI docs
• MCP server over stdio for Claude Desktop, Cline, Continue, and similar clients
• Configurable provider allowlist via environment variables

Google Support

Google support now includes a direct scraper provider implemented inside this project.

The direct Google implementation uses browser-like requests, consent cookie handling, locale-aware query parameters, and resilient HTML result parsing. It is implemented locally in this repository.

Currently supported Google providers:

Provider	Env var	Notes
Direct Google	ALLOW_UNSTABLE_PROVIDERS=true	Primary path; HTML scraping, best effort, may be blocked from datacenter IPs
serpbase.dev	SERPBASE_API_KEY	Pay-per-use; typically cheaper for low-volume usage
serper.dev	SERPER_API_KEY	Includes a free tier, then pay-per-use

Provider priority for /search/google is now google first, then google_serpbase, then google_serper.

Supported Providers

Google

Provider	Name	Method
Direct Google	google	HTML scraping with browser-like request handling
SerpBase	google_serpbase	Hosted Google SERP API
Serper	google_serper	Hosted Google SERP API

Web Search

Provider	Name	Method
DuckDuckGo	duckduckgo	HTML scraping
Bing	bing	RSS feed
Yahoo	yahoo	HTML scraping, best effort
Brave	brave	Official Search API
Mwmbl	mwmbl	Public JSON API
Ecosia	ecosia	HTML scraping
Mojeek	mojeek	HTML scraping
Startpage	startpage	HTML scraping, best effort
Qwant	qwant	Internal JSON API, best effort
Yandex	yandex	HTML scraping, best effort
Baidu	baidu	JSON endpoint, best effort

Knowledge And Reference

Provider	Name	Method
Wikipedia	wikipedia	MediaWiki API
Wikidata	wikidata	Wikidata API
Internet Archive	internet_archive	Advanced Search API
Open Library	openlibrary	Open Library search API

Developer Sources

Provider	Name	Method
GitHub	github	GitHub REST API
GitLab	gitlab	GitLab REST API
Stack Overflow	stackoverflow	Stack Exchange API
Hacker News	hackernews	Algolia HN API
Reddit	reddit	Reddit API
npm	npm	npm registry API
PyPI	pypi	HTML scraping
RubyGems	rubygems	RubyGems search API
crates.io	crates	crates.io API
lib.rs	lib_rs	HTML scraping
Docker Hub	dockerhub	Docker Hub search API
pkg.go.dev	pkg_go_dev	HTML scraping
MetaCPAN	metacpan	MetaCPAN REST API

Academic Sources

Provider	Name	Method
arXiv	arxiv	Atom API
PubMed	pubmed	NCBI E-utilities
Semantic Scholar	semanticscholar	Graph API
CrossRef	crossref	REST API

Finance Sources

Provider	Name	Key Required	Free Tier
Yahoo Finance	yahoo_finance	No	Unofficial endpoint, no key needed
Alpha Vantage	alpha_vantage	ALPHA_VANTAGE_API_KEY	25 req/day — get key
Finnhub	finnhub	FINNHUB_API_KEY	60 req/min — get key

Installation

One-command local install:

python scripts/install.py

Install, run tests, and start the HTTP API:

python scripts/install.py --dev --test --run

Deploy with Docker Compose:

python scripts/install.py --mode docker

The installer creates .env from .env.example when .env does not already exist. Existing .env files are kept unless --force-env is passed.

Manual install:

git clone https://github.com/gefsikatsinelou/MetaSearchMCP
cd MetaSearchMCP
pip install -e ".[dev]"

Or with uv:

uv pip install -e ".[dev]"

Configuration

Copy .env.example to .env and configure any providers you want to enable.

cp .env.example .env

Key settings:

HOST=0.0.0.0
PORT=8000
DEFAULT_TIMEOUT=10
AGGREGATOR_TIMEOUT=15

SERPBASE_API_KEY=
SERPER_API_KEY=
BRAVE_API_KEY=
GITHUB_TOKEN=
STACKEXCHANGE_API_KEY=
REDDIT_CLIENT_ID=
REDDIT_CLIENT_SECRET=
NCBI_API_KEY=
SEMANTIC_SCHOLAR_API_KEY=
ALPHA_VANTAGE_API_KEY=
FINNHUB_API_KEY=

ENABLED_PROVIDERS=
ALLOW_UNSTABLE_PROVIDERS=false
MAX_RESULTS_PER_PROVIDER=10

Running

HTTP API

python -m metasearchmcp.server
# or
metasearchmcp

The API starts on http://localhost:8000.

MCP Server

python -m metasearchmcp.broker
# or
metasearchmcp-mcp

The MCP server communicates over stdio.

Docker

docker build -t metasearchmcp .
docker run --rm -p 8000:8000 --env-file .env metasearchmcp

Or with Compose:

docker compose up --build

HTTP API

POST /search

Aggregate across all enabled providers or a selected provider subset.

curl -X POST http://localhost:8000/search \
  -H "Content-Type: application/json" \
  -d '{
    "query": "rust async runtime",
    "providers": ["duckduckgo", "wikipedia"],
    "params": {"num_results": 5, "max_total_results": 8, "language": "en"}
  }'

You can also narrow providers by tags:

curl -X POST http://localhost:8000/search \
  -H "Content-Type: application/json" \
  -d '{
    "query": "transformer attention",
    "tags": ["academic", "knowledge"],
    "params": {"num_results": 5, "max_total_results": 6}
  }'

When multiple tags are provided, the default behavior is tag_match="any". Set tag_match to "all" when you want providers that satisfy every requested tag:

curl -X POST http://localhost:8000/search \
  -H "Content-Type: application/json" \
  -d '{
    "query": "npm cli argument parser",
    "tags": ["code", "packages"],
    "tag_match": "all",
    "params": {"num_results": 5, "max_total_results": 6}
  }'

num_results controls how many results each provider can contribute. max_total_results caps the final merged response after deduplication.

POST /search/google

Search Google through the configured Google provider chain. If ALLOW_UNSTABLE_PROVIDERS=true, MetaSearchMCP will prefer the direct google provider automatically.

curl -X POST http://localhost:8000/search/google \
  -H "Content-Type: application/json" \
  -d '{"query": "site:github.com rust tokio"}'

To force the direct Google route explicitly:

curl -X POST http://localhost:8000/search/google \
  -H "Content-Type: application/json" \
  -d '{"query": "site:github.com rust tokio", "provider": "google"}'

GET /providers

Return the currently available provider catalog.

The response includes provider descriptions and a tag-to-provider index for quick discovery.

You can filter the catalog by tag:

curl "http://localhost:8000/providers?tag=academic&tag=web"

Use tag_match=all to require every tag instead of the default any-match behavior:

curl "http://localhost:8000/providers?tag=code&tag=packages&tag_match=all"

GET /health

Simple health check endpoint. Returns service status, version, provider count, and the current provider name list.

Response Schema

Every aggregated response includes:

• engine
• query
• results
• related_searches
• suggestions
• answer_box
• timing_ms
• providers
• errors

Every result item includes:

• title
• url
• snippet
• source
• rank
• provider
• published_date
• extra

Example response:

{
  "engine": "metasearchmcp",
  "query": "rust async runtime",
  "results": [
    {
      "title": "Tokio - An asynchronous Rust runtime",
      "url": "https://tokio.rs",
      "snippet": "Tokio is an event-driven, non-blocking I/O platform...",
      "source": "tokio.rs",
      "rank": 1,
      "provider": "duckduckgo",
      "published_date": null,
      "extra": {}
    }
  ],
  "related_searches": [],
  "suggestions": [],
  "answer_box": null,
  "timing_ms": 843.2,
  "providers": [
    {
      "name": "duckduckgo",
      "success": true,
      "result_count": 10,
      "latency_ms": 840.1,
      "error": null
    }
  ],
  "errors": []
}

MCP Tools

MetaSearchMCP exposes these MCP tools:

• search_web
• search_google
• search_academic
• search_github
• compare_engines
• search_finance
• search_code

search_web also accepts optional tags so agents can limit search to categories such as web, academic, code, or google. When multiple tags are present, tag_match="all" requires a provider to satisfy the full set. All search tools accept max_total_results to keep the final payload compact.

Example Claude Desktop config:

{
  "mcpServers": {
    "MetaSearchMCP": {
      "command": "metasearchmcp-mcp",
      "env": {
        "ALLOW_UNSTABLE_PROVIDERS": "true",
        "SERPBASE_API_KEY": "your_key",
        "SERPER_API_KEY": "your_key"
      }
    }
  }
}

Development

pip install -e ".[dev]"
pytest
uvicorn metasearchmcp.server:app --reload

Architecture

The public package is organized around these modules:

• contracts.py: request and response models
• catalog.py: provider discovery and selection
• orchestrator.py: concurrent search execution and response assembly
• merge.py: URL normalization and deduplication
• server.py: FastAPI entrypoint
• broker.py: MCP entrypoint

Legacy module names are kept as compatibility shims for earlier imports.

Roadmap

• Caching and provider-aware query reuse
• Better scoring and ranking signals across providers
• Streaming aggregation responses
• Provider health telemetry
• More first-party API integrations where they improve reliability

License

MIT