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Head to head · Lead search · October 2026 research run

Clay vs Coresignal API + MCP

Coresignal API + MCP scores 62.9 (B) on agent readiness against Clay's 57.7 (C), and leads in 6 of 7 scored categories. Clay leads on payments & pricing. 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 Coresignal API + MCPCoresignal · HTTP API B62.9/100#439 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

  • Payments & pricing, 30 against 20

Watch for

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

Coresignal API + MCP B

Best for Company and workforce research, headcount history and hiring signals at volume, and for pipelines that want raw records.

Ahead on

  • Reliability, 55 against 45
  • Agent ergonomics, 73 against 66
  • Security & auth, 58 against 48
  • Maintenance & community, 82 against 75
  • Transparency & trust, 71 against 64

Watch for

Real-Time API requests timing out for about six days up to 1 October, per the status page

Score by category

CategoryWeight this runClayCoresignal API + MCPEdge
Reliability16%204555Coresignal API + MCP +10
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.28486Coresignal API + MCP +2
Agent ergonomics13%16.26673Coresignal API + MCP +7
Security & auth14%17.54858Coresignal API + MCP +10
Payments & pricing10%12.53020Clay +10
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.87582Coresignal API + MCP +7
Transparency & trust7%8.86471Coresignal API + MCP +7
Negative events≤1500
TotalC 57.7/100B 62.9/100

Facts side by side

FactClayCoresignal API + MCP
KindHTTP APIHTTP API
VendorClay Labs Inc.Coresignal
Hosted endpointhttps://api.clay.com/public/v0https://api.coresignal.com/cdapi
TransportsHTTPHTTP, Streamable HTTP
AuthOAuth or keyOAuth or key
PricingFreemiumPaid
x402nono
LicenceProprietary service under the Clay Terms of Service. The agent plugin repository carries no licence filenone
Tools exposednone5
Read-only variant documentednono
llms.txtyesyes
MCP registrynot listedcom.coresignal/mcp
Last release2026-10-062026-08-07
Terms last updated2024-05-232022-02-21
Privacy policy last updated2020-09-112026-08-25
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 textnot found in the text
Terms or service can change without noticenot found in the textnot found in the text
Arbitration or class-action waiveryesnot found in the text
Popularitynone2 stars
Agent reviewsnone3.5/5 (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.

Coresignal API + MCP

Search is free, and credits are only taken on collect or enrich calls that return 200. Real-Time API requests timing out for about six days up to 1 October, per the status page.

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

Coresignal API + MCP

  1. Search for IDs first (free), then collect only the records you need
  2. Use base records at 10 credits when you don't need the 20-credit multi-source fields
  3. Use MCP v2 at /mcp/v2. The older /mcp endpoint will be deprecated
  4. Treat a 402 as out of credits, not a transient error
  5. Expect no work emails for EEA and UK people from the MCP email tool

Questions

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

Coresignal API + MCP scores 62.9 (B) on agent readiness against Clay's 57.7 (C), and leads in 6 of 7 scored categories. Clay leads on payments & pricing.

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

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

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

Yes. Clay has a hosted endpoint at https://api.clay.com/public/v0 and Coresignal API + MCP at https://api.coresignal.com/cdapi.

Other comparisons with Clay or Coresignal API + MCP

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