## Recommendation: Valyu For AyuMitraAI — a FastAPI + LangChain + Cerebras medical symptom-triage agent with no existing retrieval layer — the best fit is **Valyu** (`api.valyu.ai/v1/search`). **Why Valyu wins for this repo:** - **Licensed, medical-grade sources** — the explicit requirement. Valyu indexes PubMed, MedRxiv, BioRxiv, clinical trials, and closed-access licensed journals/books with **full-text retrieval**, not scraped SERPs. For a clinical-triage agent, grounding in peer-reviewed medical literature is the single most important factor, and Valyu is the only candidate purpose-built around licensed academic/medical corpora. - **Drop-in fit** — LangChain/LlamaIndex compatible, so it slots beside the existing `langchain_agents.py` / `cerebras_service.py` chains. Simple `x-api-key` auth fits the existing `config.py` env pattern (alongside `CEREBRAS_API_KEY`). - **Pay-per-result pricing** ($0.003/web result, $0.01+/proprietary) — no subscriptions, easy to gate behind the symptom-analysis endpoint. - **Source filtering** (`included_sources`, date ranges, citation/DOI metadata) lets the agent cite reputable references back to clinicians. **Main alternatives considered:** - **Linkup** — strong "licensed, no-scraping" model with publisher deals, but coverage is **business/corporate-focused** (Statista, Xerfi, news). No medical/academic depth — wrong domain. - **Perplexity Sona