* feat(community): add Serper web search provider
Add a new community search provider backed by the Serper Google Search
API (https://serper.dev). Serper returns real-time Google results via a
simple JSON API and requires only an API key — no extra Python package.
Changes:
- backend/packages/harness/deerflow/community/serper/__init__.py
- backend/packages/harness/deerflow/community/serper/tools.py
Implements web_search_tool using httpx (already a project dependency).
API key is read from config.yaml `api_key` field or SERPER_API_KEY env var.
Follows the same interface / output shape as the existing ddg_search provider.
Exposes max_results parameter (default 5) with config override logic.
- backend/tests/test_serper_tools.py
Unit tests covering API key resolution, config overrides, HTTP errors,
empty results, and parameter passing.
- config.example.yaml: add commented-out Serper example alongside other providers
- .env.example: add SERPER_API_KEY placeholder
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
* Fix the lint error
* Fix the lint error
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Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>
Co-authored-by: Willem Jiang <willem.jiang@gmail.com>