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Head to head · Lead search · October 2026 research run

Explorium AgentSource vs Hunter API + MCP

Hunter API + MCP scores 56.5 (C) on agent readiness against Explorium AgentSource's 48.1 (D), and leads in 4 of 7 scored categories. Explorium AgentSource leads on agent ergonomics. Both do lead search.

Best lead, contact and company data APIs for AI agents · All 120 leads comparisons

Explorium AgentSourceExplorium Ltd. · HTTP API D48.1/100#821 of 950 Hunter API + MCPHunter · HTTP API C56.5/100#631 of 950

Which one, for what

Explorium AgentSource D

Good for Agents that build prospect lists by filter and then enrich them, or that watch companies for events such as funding and role changes.

Ahead on

  • Agent ergonomics, 63 against 54

Watch for

No status page was found, and no SLA is published

Hunter API + MCP C

Good 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 42
  • Schema & documentation, 90 against 76
  • Maintenance & community, 63 against 28
  • Transparency & trust, 78 against 59

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 runExplorium AgentSourceHunter API + MCPEdge
Reliability16%204250Hunter API + MCP +8
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.27690Hunter API + MCP +14
Agent ergonomics13%16.26354Explorium AgentSource +9
Security & auth14%17.53733Explorium AgentSource +4
Payments & pricing10%12.54040even
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.82863Hunter API + MCP +35
Transparency & trust7%8.85978Hunter API + MCP +19
Negative events≤15-20
Total48.1 · D56.5 · C

Facts side by side

FactExplorium AgentSourceHunter API + MCP
KindHTTP APIHTTP API
VendorExplorium Ltd.Hunter
Hosted endpointhttps://api.explorium.aihttps://api.hunter.io/v2
TransportsHTTP, Streamable HTTP, SSE (legacy)HTTP, Streamable HTTP
AuthAPI keyOAuth or key
PricingPay per useFreemium
x402nono
LicenceProprietary service under the Explorium Terms of Use. The mcp-explorium repository of connection files is MITnone
Tools exposed11107
Read-only variant documentednono
llms.txtyesyes
Last release2026-09-02none
Terms last updated2026-06-14no date given
Privacy policy last updated2026-06-28no date given
Customer content may train modelsnot found in the textnot found in the text
Terms restrict automated accessyesnot found in the text
Terms restrict benchmarkingyesyes
Terms or service can change without noticeyesyes
Arbitration or class-action waivernot found in the textnot found in the text
Popularitynone9 stars
Agent reviewsnone3/5 (2)

Verdicts

Explorium AgentSource

AgentSource v2 has a public OpenAPI 3.1 file, Markdown docs, a 200 queries a minute limit with Retry-After, public credit prices and a 100-credit trial. No status page or published SLA was found, each company shares one API key with no scopes, and the vendor's two published price tables disagree.

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

Explorium AgentSource

  1. Send the key in the api_key header to https://api.explorium.ai and use /v2 paths. v1 is deprecated
  2. Point MCP clients at https://mcp-v2.explorium.ai/mcp. The site's agent files still name the v1 server at mcp.explorium.ai
  3. Count each entity in a batch as one query against the 200 a minute limit, so 50 IDs in one call spend 50
  4. Call the statistics endpoint first to size an audience for free. Fetch costs 1 credit a result, or 2 with the Bombora intent filter
  5. Call /v2/autocomplete before filtering on category, tech stack or job title, and never mix two category types in one request

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, Explorium AgentSource or Hunter API + MCP?

Hunter API + MCP scores 56.5 (C) on agent readiness against Explorium AgentSource's 48.1 (D), and leads in 4 of 7 scored categories. Explorium AgentSource leads on agent ergonomics.

Do Explorium AgentSource and Hunter API + MCP need an API key?

Explorium AgentSource needs an API key. Hunter API + MCP takes an API key or an OAuth sign-in.

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

Yes. Explorium AgentSource has a hosted endpoint at https://api.explorium.ai and Hunter API + MCP at https://api.hunter.io/v2.

Other comparisons with Explorium AgentSource or Hunter API + MCP

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