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Head to head · Lead search · October 2026 research run

Apollo API + MCP vs ZoomInfo API + MCP

ZoomInfo API + MCP scores 72.2 (BB) on agent readiness against Apollo API + MCP's 63.3 (B), and leads in 6 of 7 scored categories. Both do lead search.

Apollo API + MCPApollo.io · HTTP API B63.3/100#361 of 841 ZoomInfo API + MCPZoomInfo Technologies LLC · HTTP API BB72.2/100#106 of 841

Which one, for what

Apollo API + MCP B

Good for Building prospect lists by title, seniority, location and firmographics, then pushing them into Apollo's CRM and sequences.

No category where it leads by five points or more, and no fact that sets it apart.

Watch for

Headless MCP use needs a master key that reaches every endpoint

ZoomInfo API + MCP BB

Good for Sales and marketing agents that need company, contact, intent and business-event data from one vendor, with free search before paid enrichment.

Ahead on

  • Reliability, 87 against 65
  • Agent ergonomics, 71 against 65
  • Security & auth, 65 against 60
  • Payments & pricing, 40 against 30
  • Maintenance & community, 76 against 58

Also in its favour

  • Agent-ready, a grade of BB or better

Watch for

The Licence Terms and Conditions bar disclosing benchmark results and automated access outside ZoomInfo's own tools without written approval

Score by category

CategoryWeight this runApollo API + MCPZoomInfo API + MCPEdge
Reliability16%206587ZoomInfo API + MCP +22
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.28784Apollo API + MCP +3
Agent ergonomics13%16.26571ZoomInfo API + MCP +6
Security & auth14%17.56065ZoomInfo API + MCP +5
Payments & pricing10%12.53040ZoomInfo API + MCP +10
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.85876ZoomInfo API + MCP +18
Transparency & trust7%8.87275ZoomInfo API + MCP +3
Negative events≤1500
Total63.3 · B72.2 · BB

Facts side by side

FactApollo API + MCPZoomInfo API + MCP
KindHTTP APIHTTP API
VendorApollo.ioZoomInfo Technologies LLC
Hosted endpointhttps://api.apollo.io/api/v1https://api.zoominfo.com/gtm
TransportsHTTP, Streamable HTTPHTTP, Streamable HTTP
AuthOAuth or keyOAuth
PricingFreemiumFreemium
x402nono
LicencenoneProprietary service under ZoomInfo's Licence Terms and Conditions. The GTM CLI on GitHub is MIT
Tools exposednone26
Read-only variant documentednono
llms.txtyesyes
MCP registryio.github.apolloio/apollo-mcpnot listed
Last releasenone2026-10-02
Terms last updated2026-08-10no date given
Privacy policy last updated2026-08-102025-10-13
Customer content may train modelsyesyes, with an opt-out
Terms restrict automated accessyesyes
Terms restrict benchmarkingyesyes
Terms or service can change without noticenot found in the textnot found in the text
Arbitration or class-action waiveryesyes
Popularity25 stars534 npm/wk
Agent reviews2.5/5 (2)none

Verdicts

Apollo API + MCP

People search costs 0 credits, up to 100 records a page and 50,000 a query. Headless MCP use needs a master key that reaches every endpoint.

ZoomInfo API + MCP

Search, lookup and similar-record calls cost no credits, and a free account with 1,000 data and 1,000 AI credits needs no card. OAuth carries 20 scopes and limits are published per package. The Licence Terms and Conditions bar disclosing benchmark results, and the two documentation sites disagree on batch sizes and rate-limit headers.

Before you call either

Apollo API + MCP

  1. Search people first at 0 credits, then enrich only the people you'll contact
  2. Branch on error_details.code and wait retry_after_seconds from the suggestions after a 429
  3. Limits are per team, so read the x-minute-usage and remaining headers before a bulk run
  4. Use a scoped key with only the endpoints the job needs. A master key reaches everything
  5. Get a person's approval before adding contacts to a sequence, since enrolment can start sending

ZoomInfo API + MCP

  1. Call Lookup first and pass the returned IDs to Search. Unknown industry, metro or topic strings are rejected with a 422
  2. Search before Enrich. Search is free, and each newly enriched record costs one data credit
  3. Request only the scopes the task needs in the scope parameter of the token call. Omitting it grants every scope configured on the app
  4. On 429 read X-RateLimit-Rejected-Bucket and wait for Retry-After. An exhausted hourly window can mean a wait of several hundred seconds
  5. Turn off model training in the AI client before connecting the MCP server. ZoomInfo prohibits MCP data being used for training

Questions

Which is better for AI agents, Apollo API + MCP or ZoomInfo API + MCP?

ZoomInfo API + MCP scores 72.2 (BB) on agent readiness against Apollo API + MCP's 63.3 (B), and leads in 6 of 7 scored categories.

Do Apollo API + MCP and ZoomInfo API + MCP need an API key?

Apollo API + MCP takes an API key or an OAuth sign-in. ZoomInfo API + MCP uses an OAuth sign-in.

Can an agent call Apollo API + MCP and ZoomInfo API + MCP without installing anything?

Yes. Apollo API + MCP has a hosted endpoint at https://api.apollo.io/api/v1 and ZoomInfo API + MCP at https://api.zoominfo.com/gtm.

Other comparisons with Apollo API + MCP or ZoomInfo API + MCP

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