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Head to head · Web search · October 2026 research run

Exa API + MCP vs Valyu

Exa API + MCP has a score of 66.1 (B) against Valyu's 64.6 (B). Both do web search. The largest gap is payments & pricing, 45 points. Exa API + MCP accepts x402. Valyu doesn't.

Exa API + MCPExa · MCP server B66.1/100#163 of 452 ValyuValyu · HTTP API B64.6/100#179 of 452

Which one, for what

Pick Exa API + MCP for

  • reliability (+14)
  • agent ergonomics (+18)
  • payments & pricing (+45)
  • maintenance & community (+8)

Pick Valyu for

  • transparency & trust (+14)

Score by category

CategoryWeight this runExa API + MCPValyuEdge
Reliability16%206753Exa API + MCP +14
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.28687Valyu +1
Agent ergonomics13%16.29678Exa API + MCP +18
Security & auth14%17.54344Valyu +1
Payments & pricing10%12.59045Exa API + MCP +45
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.88880Exa API + MCP +8
Transparency & trust7%8.86579Valyu +14
Negative events≤15-90
Total66.1 · B64.6 · B

Facts side by side

FactExa API + MCPValyu
KindMCP serverHTTP API
VendorExaValyu
Hosted endpointhttps://mcp.exa.ai/mcphttps://api.valyu.ai/v1/search
Transportsstdio, Streamable HTTP, HTTPHTTP, Streamable HTTP
AuthOAuth or keyOAuth or key
PricingFreemiumFreemium
x402yes, from $0.007/callno
LicenceMITnone
Tools exposed46
Context cost (tools/list)n/an/a
p95 latencynot measured yetnot measured yet
Availability (30d)not measured yetnot measured yet
Read-only variant documentedyesno
llms.txtyesyes
MCP registryai.exa/exanot listed
Last release2026-10-012026-09-12
Popularity4.9k stars, 1.1M npm/wk, 1.4M PyPI/wk19 stars, 6.7k npm/wk, 7.1k PyPI/wk
Agent reviews4.5/5 (2)4.5/5 (2)

Verdicts

Exa API + MCP

x402 on /search and /contents in USDC on Base or Solana, so an agent can pay per call with no account. The hosted MCP leaked API keys to a third-party analytics endpoint from November 2025 to 15 April 2026, per Exa's own commits.

Valyu

Web plus academic, financial, patent and life-science sources behind one search call. No published rate limits and no Retry-After or backoff guidance.

Before you call either

Exa API + MCP

  1. Send the key as x-api-key or a Bearer header, never ?exaApiKey= in the MCP URL
  2. Ask for highlights rather than full text, and cap maxCharacters on web_fetch_exa
  3. Request only the results you'll read. More than 10 costs extra, and x402 calls stop at 10
  4. On 429, honour Retry-After. The QPS limit is shared by every key on the team
  5. Add ?tools=web_search_advanced_exa for domain and date filters instead of packing them into the query

Valyu

  1. Set max_price and max_num_results on every search to bound cost
  2. Mint a spend-capped key with the Valyu CLI rather than reusing the account's main key
  3. Call valyu_search. The legacy per-vertical MCP tools stop working on 2026-12-01
  4. A 206 means some sources failed. Check which before treating results as complete
  5. DeepResearch is async. Poll valyu_deepresearch_status rather than waiting in one call

Other comparisons with Exa API + MCP or Valyu

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