multi-search-engine

A unified CLI for querying several web search engines in parallel and returning a normalized result list. Built on httpx and beautifulsoup4 (both already in OpenSquilla default dependencies, so no extra install beyond pip install opensquilla).

Use cases

• Building a deep-research round with diverse engine coverage
• Fact-check a claim against >1 engine
• Compare scholarly metadata coverage with general web results
• Find citable publication metadata without requiring an API key

Limitations

• A single engine sufficient → call its API directly instead
• Need headless-browser DOM rendering → this skill is HTTP-only

Quick start

python {baseDir}/scripts/search.py \
    --query "openclaw skill registry" \
    --engines crossref,duckduckgo,brave \
    --limit 10 \
    --json

Output:

{
  "query": "...",
  "results": [
    {
      "engine": "crossref",
      "title": "...",
      "url": "https://...",
      "snippet": "...",
      "rank": 1,
      "doi": "10.1234/example",
      "year": 2024,
      "authors": ["Ada Example", "Edge Research Consortium"],
      "corporate_authors": ["Edge Research Consortium"]
    }
  ],
  "errors": [
    {"engine": "brave", "reason": "BRAVE_SEARCH_API_KEY/BRAVE_API_KEY not set; skipping"}
  ]
}

doi, year, authors, and corporate_authors are optional. They are emitted only when an engine supplies verifiable values, so the existing five-field web-result shape remains compatible for general engines. The parallel corporate-author list lets BibTeX consumers protect institution names from person-name parsing.

Engines

The script never errors out when an API-key engine's key is missing — it records a per-engine errors entry and continues with the rest. Pass --strict to fail fast when any requested engine is unavailable.

Routing tips

The host should pick engines by language and availability:

• Academic queries → crossref first, then brave or tavily for broader context
• General web queries → duckduckgo plus brave or tavily for triangulation
• Time-sensitive (last 24h) → brave (recency filter) or tavily
• Long-tail academic → start with crossref; supplement with direct arXiv when needed

engines.md has the full per-engine guidance.

Boundaries

• HTTP-only. JS-rendered pages will not be readable; use a headless-browser skill if needed.
• DuckDuckGo scraping is best-effort — HTML structure changes can break it. The script logs parse failures individually and keeps the run going.
• Timeout, HTTP 429, and transient HTTP 5xx responses receive at most two retries with bounded backoff. Repeated failures remain per-engine soft errors. Callers must still avoid high-rate loops.
• Captcha-protected results are not bypassed. If an engine returns a challenge page, the parser will return zero results for that engine and log a warning.

Crossref is a public metadata service, not a full-text search index. The client sends query.bibliographic, respects the requested result limit, and uses canonical https://doi.org/<doi> URLs. Set CROSSREF_MAILTO to identify your application through Crossref's polite-pool convention. See the Crossref REST API etiquette and rate-limit documentation.