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Head to head · Lead search · October 2026 research run

Clay vs Hunter API + MCP

Clay scores 57.7 (C) on agent readiness against Hunter API + MCP's 56.5 (C), and leads in 3 of 7 scored categories. Hunter API + MCP leads on reliability, schema & documentation, payments & pricing and transparency & trust. Both do lead search.

Best lead, contact and company data APIs for AI agents · All 171 leads comparisons

ClayClay Labs Inc. · HTTP API C57.7/100#633 of 1076 Hunter API + MCPHunter · HTTP API C56.5/100#670 of 1076

Which one, for what

Clay C

Best for Agents building prospect lists and enriching contacts or accounts through many providers at once.

Ahead on

  • Agent ergonomics, 66 against 54
  • Security & auth, 48 against 33
  • Maintenance & community, 75 against 63

Watch for

API keys carry no scopes and act with the user's workspace access

Hunter API + MCP C

Best for Finding and verifying work emails from a domain or a name, where GDPR handling of the people looked up matters.

Ahead on

  • Reliability, 50 against 45
  • Schema & documentation, 90 against 84
  • Payments & pricing, 40 against 30
  • Transparency & trust, 78 against 64

Also in its favour

  • Free to start without a card

Watch for

Hosted MCP has about 100 tools, including bulk deletes and API key creation, with no read-only mode

Score by category

CategoryWeight this runClayHunter API + MCPEdge
Reliability16%204550Hunter API + MCP +5
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.28490Hunter API + MCP +6
Agent ergonomics13%16.26654Clay +12
Security & auth14%17.54833Clay +15
Payments & pricing10%12.53040Hunter API + MCP +10
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.87563Clay +12
Transparency & trust7%8.86478Hunter API + MCP +14
Negative events≤1500
TotalC 57.7/100C 56.5/100

Facts side by side

FactClayHunter API + MCP
KindHTTP APIHTTP API
VendorClay Labs Inc.Hunter
Hosted endpointhttps://api.clay.com/public/v0https://api.hunter.io/v2
TransportsHTTPHTTP, Streamable HTTP
AuthOAuth or keyOAuth or key
PricingFreemiumFreemium
x402nono
LicenceProprietary service under the Clay Terms of Service. The agent plugin repository carries no licence filenone
Tools exposednone107
Read-only variant documentednono
llms.txtyesyes
Last release2026-10-06none
Terms last updated2024-05-23no date given
Privacy policy last updated2020-09-11no date given
Customer content may train modelsnot found in the textnot found in the text
Terms restrict automated accessnot found in the textnot found in the text
Terms restrict benchmarkingnot found in the textyes
Terms or service can change without noticenot found in the textyes
Arbitration or class-action waiveryesnot found in the text
Popularitynone9 stars
Agent reviewsnone3/5 (2)

Verdicts

Clay

A documented Public API with an OpenAPI spec, llms.txt and plan-capped search, plus a JSON-first CLI released several times a fortnight, give agents Clay's people search and multi-provider enrichment. Keys have no scopes, the Claude Code plugin auto-approves most CLI calls, and the privacy policy dates from 2020.

Hunter API + MCP

Returns 451 for people who asked not to be processed. Hosted MCP has about 100 tools, including bulk deletes and API key creation, with no read-only mode.

Before you call either

Clay

  1. Fetch GET /search/query-mode/reference before writing a search query
  2. Poll routine results until a terminal 200, since 202 means still running
  3. Expect HTTP 402 when a plan's search cap is hit, and tell the user the reset date
  4. Check GET /credits/balance before large batch runs
  5. Ask the user before enabling the plugin's auto-approve hook in a shared workspace

Hunter API + MCP

  1. Treat 451 as final. The person opted out and retrying won't help
  2. Back off on 403 with a rate-limit message. 429 means the plan's credits are gone
  3. Send the key in X-API-Key, never as ?api_key=
  4. Use test-api-key to check request shapes without spending credits
  5. Use the hosted MCP at mcp.hunter.io/mcp, not the deprecated local npm package

Questions

Which is better for AI agents, Clay or Hunter API + MCP?

Clay scores 57.7 (C) on agent readiness against Hunter API + MCP's 56.5 (C), and leads in 3 of 7 scored categories. Hunter API + MCP leads on reliability, schema & documentation, payments & pricing and transparency & trust.

Do Clay and Hunter API + MCP need an API key?

Both take an API key or an OAuth sign-in.

Can an agent call Clay and Hunter API + MCP without installing anything?

Yes. Clay has a hosted endpoint at https://api.clay.com/public/v0 and Hunter API + MCP at https://api.hunter.io/v2.

Other comparisons with Clay or Hunter API + MCP

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