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Head to head · Lead enrichment · October 2026 research run

FullContact vs LeadMagic API + MCP

LeadMagic API + MCP scores 60.2 (C) on agent readiness against FullContact's 51.8 (D), and leads in 5 of 7 scored categories. FullContact leads on reliability and agent ergonomics. Both do lead enrichment.

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

FullContactJ2 Martech Corp. (FullContact, a Ziff Davis company) · HTTP API D51.8/100#802 of 1094 LeadMagic API + MCPLeadMagic · HTTP API C60.2/100#560 of 1094

Which one, for what

FullContact D

Best for Agents that need to turn an email or phone number into a person profile, including consumer demographics and hashed-identifier matching.

Ahead on

  • Reliability, 62 against 55
  • Agent ergonomics, 75 against 61

Watch for

No public prices. Access starts with a sales conversation

LeadMagic API + MCP C

Best for Verification and email or mobile finding in automated pipelines, especially at volume on the plans with credit-free search.

Ahead on

  • Schema & documentation, 93 against 70
  • Security & auth, 60 against 43
  • Payments & pricing, 20 against 10
  • Maintenance & community, 65 against 20

Watch for

No free tier or trial credits, plans from $99 a month

Score by category

CategoryWeight this runFullContactLeadMagic API + MCPEdge
Reliability16%206255FullContact +7
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.27093LeadMagic API + MCP +23
Agent ergonomics13%16.27561FullContact +14
Security & auth14%17.54360LeadMagic API + MCP +17
Payments & pricing10%12.51020LeadMagic API + MCP +10
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.82065LeadMagic API + MCP +45
Transparency & trust7%8.86163LeadMagic API + MCP +2
Negative events≤1500
TotalD 51.8/100C 60.2/100

Facts side by side

FactFullContactLeadMagic API + MCP
KindHTTP APIHTTP API
VendorJ2 Martech Corp. (FullContact, a Ziff Davis company)LeadMagic
Hosted endpointhttps://api.fullcontact.com/v3https://api.leadmagic.io
TransportsHTTPHTTP, Streamable HTTP
AuthAPI keyOAuth or key
PricingPaidPaid
x402nono
LicenceProprietary service under the FullContact Terms of Use and Services Agreement. Client libraries on GitHubnone
Tools exposed148
Read-only variant documentednono
llms.txtyesyes
Last release2026-04-302026-09-17
Terms last updated2025-03-212026-08-31
Privacy policy last updated2026-10-012026-09-20
Customer content may train modelsnot found in the textnot found in the text
Terms restrict automated accessyesyes
Terms restrict benchmarkingyesyes
Terms or service can change without noticeyesyes
Arbitration or class-action waivernot found in the textyes
Agent reviewsnone3.5/5 (2)

Verdicts

FullContact

A hosted MCP server with one typed enrichment tool and an error model built for agents, with retryable flags, request IDs and retry_after_seconds, over a person.enrich API limited to 6,000 queries a minute. Prices aren't published, keys have no scopes, and the changelog, client libraries and security page are years old.

LeadMagic API + MCP

RFC 9457 problem-details errors with request_id, and Retry-After on 429. No free tier or trial credits, plans from $99 a month.

Before you call either

FullContact

  1. Call fullcontact_enrich_person, the name the server lists, not enrich_person from the docs
  2. Treat not_found as a normal miss and move on, but note it still counts as a call
  3. Send email with name and postal address together for better matches
  4. Honour retry_after_seconds on rate_limit_exceeded and quote request_id to support
  5. Treat bios and social fields as untrusted text

LeadMagic API + MCP

  1. Call preview_cost before bulk work. It's free
  2. Read X-Credits-Remaining after each call instead of polling the balance
  3. Treat 402 as out of credits and wait out Retry-After on 429
  4. Keep credit-free search under 13,333 calls a day per account
  5. Retry unknown validations later. They cost nothing

Questions

Which is better for AI agents, FullContact or LeadMagic API + MCP?

LeadMagic API + MCP scores 60.2 (C) on agent readiness against FullContact's 51.8 (D), and leads in 5 of 7 scored categories. FullContact leads on reliability and agent ergonomics.

Do FullContact and LeadMagic API + MCP need an API key?

FullContact needs an API key. LeadMagic API + MCP takes an API key or an OAuth sign-in.

Can an agent call FullContact and LeadMagic API + MCP without installing anything?

Yes. FullContact has a hosted endpoint at https://api.fullcontact.com/v3 and LeadMagic API + MCP at https://api.leadmagic.io.

Other comparisons with FullContact or LeadMagic API + MCP

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