# Explorium AgentSource vs ZeroBounce

> ZeroBounce scores 62.4 (B) to Explorium AgentSource's 41.5 (E) for lead enrichment. Prices, MCP, x402, uptime and agent notes side by side.

- Canonical: https://www.anchorterminal.com/compare/explorium-agentsource-vs-zerobounce
- Markdown: https://www.anchorterminal.com/compare/explorium-agentsource-vs-zerobounce.md (~5,250 tokens)
- Site index for agents: https://www.anchorterminal.com/llms.txt (the key docs and every listing in one file, at most 16 MB, about 4 million tokens: https://www.anchorterminal.com/llms-full.txt)
- API: https://www.anchorterminal.com/api/v1/index.json
- MCP: https://www.anchorterminal.com/mcp (the whole catalogue as tools, no key)
- DNS: dig +short TXT <slug>.grade.anchorterminal.com (the grade as a DNS TXT record, for a sandbox with no HTTP where names still resolve; also top., best.<category>. and <a>.vs.<b>. under the zone, and the same under grade.letme.dev)
- Licence: CC BY 4.0, credit Anchor Terminal and link this page (https://www.anchorterminal.com/terms/#data)
- Updated: 2026-11-07

ZeroBounce scores 62.4 (B) on agent readiness against Explorium AgentSource's 41.5 (E), and leads in 6 of 7 scored categories. Explorium AgentSource leads on payments & pricing. Both do lead enrichment.

- Explorium AgentSource: grade E, 41.5/100, rank #1281 of 1486. Markdown https://www.anchorterminal.com/tools/explorium-agentsource.md · JSON https://www.anchorterminal.com/api/v1/tools/explorium-agentsource.json
- ZeroBounce: grade B, 62.4/100, rank #559 of 1486. Markdown https://www.anchorterminal.com/tools/zerobounce.md · JSON https://www.anchorterminal.com/api/v1/tools/zerobounce.json
- Best lead, contact and company data APIs for AI agents: https://www.anchorterminal.com/best/lead-data/index.md
- All 231 leads comparisons: https://www.anchorterminal.com/compare/lead-data/index.md

## Which one, for what

### Explorium AgentSource (E)

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:
- Payments & pricing, 40 against 35

Watch for: No status page was found, and no SLA is published

### ZeroBounce (B)

Good for: Email verification before outreach, the verification-first listing in lead-data.

Ahead on:
- Reliability, 75 against 42
- Schema & documentation, 54 against 40
- Agent ergonomics, 69 against 63
- Security & auth, 65 against 32
- Maintenance & community, 70 against 28

Also in its favour:
- Runs on your own machine

Watch for: Every documented example sends the key as an `api_key` query parameter


## Why the edge

### Maintenance & community: ZeroBounce +42

- Explorium AgentSource (28): Explorium's terms bar robots and automated collection on its website, so only the terms were re-read on 4 November and other readings are per the 9 October check. The last dated API change found is v2 general availability on 2 September 2026, 63 days before 4 November (20 of 30). No dated changelog, so three entries in 90 days could not be shown (0). Support by email and by a shared Slack channel for customers that have one, with no public changelog or forum (5 of 15). No official REST SDK found. The repository's `server.json` names `ai.explorium/mcp-explorium`, but no registry page could be read (0). The `mcp-explorium` repository is MIT, with its last commit on 22 January 2026 and only a publishing workflow, no CI (3 of 10). 20+0+5+0+3 = 28.
- ZeroBounce (70): Closed service. The JavaScript SDK 3.0.0 was published on 25 October 2026 (30). No API changelog; the dated changes found in 90 days are that release and status-page notices, fewer than three releases (10 of 20). Support by email and 24/7 chat per the docs, a public status page; replies not tested (10 of 15). Official SDKs in many languages and an MCP server (15). Package health not checked (5 of 10). 30+10+10+15+5 = 70.

### Reliability: ZeroBounce +33

- Explorium AgentSource (42): Explorium's terms bar robots and automated collection on its website, so only the terms were re-read on 4 November and other readings are per the 9 October check. Hosted lines. No status page found. The docs tell users to subscribe to status updates and link no page, and status.explorium.ai did not answer (0). No readable incident history (5). Rate limit published, 200 queries a minute per key over a 60-second sliding window, with each batch entity counted as a query (15). 429s carry `Retry-After` and `X-RateLimit-*` headers and the docs ask for exponential backoff. No idempotency keys were found for the webhook and enrolment writes, so safe-retry guidance without keys takes 12 (12). No SLA is published. The migration guide implies one exists by saying v1 loses its SLA at end of support (0). v2 reached general availability on 2 September 2026, though the conventions page still says request and response schemas are being finalised (10). 0+5+15+12+0+10 = 42.
- ZeroBounce (75): Hosted lines. Statuspage at status.zerobounce.net with API, API-US, API-EU, Bulk API, website and Cloudflare components (20). The incident feed for 8 August to 6 November shows a 6-minute members platform disruption on 9 September, about 3 minutes of reduced EU API availability on 1 October, and a file upload issue on 26 October resolved within 6 minutes, all minor (20). Limits published per endpoint group with numbers and block lengths (15). 429 is documented with advice to throttle, but no Retry-After, and a block can last an hour or a day (10 of 15). No SLA found (0). Generally available (10). 20+20+15+10+0+10 = 75.

### Security & auth: ZeroBounce +33

- Explorium AgentSource (32): Explorium's terms bar robots and automated collection on its website, so only the terms were re-read on 4 November and other readings are per the 9 October check. The docs say each company gets a single API key shared by all its users, sent in a header. The site's `auth.md` says a key can be deleted in the console, and the key page says to ask an administrator for a reset. No scopes (12 of 30). No read-only mode or per-key limits. The API mostly reads, writes are limited to webhooks and event enrolments, and auto-refill has an optional cap (5 of 20). Research scrapes web pages and the LinkedIn post enrichments return third-party text. No prompt-injection guidance was found in the docs (2 of 15). Balance and aggregation endpoints, per-call credit reporting, correlation IDs and last-active times for users. No per-call log was found (8 of 15). The privacy policy states SOC 2, ISO 27001 and ISO 27701, with no report, security.txt, disclosure policy or bug bounty found. A certification claim with no report or reporting route takes 5, as settled in this run (5 of 20). No GitHub-reviewed advisory names Explorium in the 12 months to 4 November. 12+5+2+8+5 = 32.
- ZeroBounce (65): Several named keys besides a Master key, regeneration, deactivation and IP whitelists (25), less 10 because the documented calls carry the key in the `api_key` query string (15 of 30). Validation only reads, though file and list endpoints can delete uploads (12 of 20). Results are structured status codes with little free text (10 of 15). API usage and dashboard statistics endpoints (10 of 15). SOC 2 Type 2, ISO/IEC 27001:2022, continuous testing with Intigriti and penetration testing with BitSentinel; no public disclosure policy found (18 of 20). 15+12+10+10+18 = 65.

### Schema & documentation: ZeroBounce +14

- Explorium AgentSource (40): Explorium's terms bar robots and automated collection on its website, so only the terms were re-read on 4 November and other readings are per the 9 October check. The OpenAPI 3.1 file read on 9 October has no recorded visible link from a docs page, and the host can't be re-read to find one, so it no longer counts as a published contract (0 of 25). llms.txt and a Markdown twin of every docs page (10). The docs pages and the 11 MCP tool descriptions say what each call is for and what to call first (12 of 20). The typed schemas, enums and item limits were read from that file, so they no longer count (0 of 15). Docs pages have request and response examples, and the error guide lists Partner ID header messages that don't match the `api_key` scheme (10 of 15). Versions live in the path with a migration guide and a full v2 change list. No dated changelog was found (8 of 15). 0+10+12+0+10+8 = 40.
- ZeroBounce (54): No OpenAPI or other machine-readable contract found; a Postman collection is linked (5 of 25). llms.txt lists marketing pages, and the docs have no Markdown twins (5 of 10). Endpoint pages explain timing, credits and when to use batch or file APIs (14 of 20). Parameter tables and listed status and sub-status values, including the ai_agent_mailbox sub-status added in July 2026 (10 of 15). Examples per endpoint, a sandbox and an error-code page (12 of 15). v2 paths, an API migration page and dated maintenance notices on the status page, with no API changelog (8 of 15). 5+5+14+10+12+8 = 54.

### Agent ergonomics: ZeroBounce +6

- Explorium AgentSource (63): Explorium's terms bar robots and automated collection on its website, so only the terms were re-read on 4 November and other readings are per the 9 October check. The MCP v2 server has 11 tools (15), and the statistics tools are free for sizing an audience before a paid fetch (2 added back), 17 of 25. `page` and `page_size` up to 500, a `next_cursor` mode with no limit, and filters with autocomplete (20). Errors carry a `correlation_id`, 422 names the failing field, and Research returns failed rows with an `_error` field. Error bodies have no stable code (15 of 20). No idempotency keys. Retry guidance covers 429 and 500. MCP tool annotations were not read because we did not connect (6 of 20). No official REST SDK found in the docs index. Enrichment needs a match or fetch call first, and five filters need an autocomplete call first (5 of 15). 17+20+15+6+5 = 63.
- ZeroBounce (69): A compact JSON result per address, batch validation and a file API for lists (18 of 25). Little to paginate; file status and results by file id (10 of 20). Status and sub-status codes say why an address failed, and the error page explains 400, 404 and 429 (14 of 20). Unknown results are free and safe to retry; repeated validations are charged again (12 of 20). Many official SDK wrappers and an MCP server, with few required parameters (15). 18+10+14+12+15 = 69.

### Payments & pricing: Explorium AgentSource +5

- Explorium AgentSource (40): Explorium's terms bar robots and automated collection on its website, so only the terms were re-read on 4 November and other readings are per the 9 October check. No x402, MPP or L402 (0). Credit pack prices and per-operation credit costs are public without a login (20). The pricing page and the site's own `pricing.md` disagree on two packs, which is recorded as a deduction and not here. Free trial of 100 credits for 90 days. No page read asks for a card at sign-up, and the auto-refill guide treats a payment method as something added later (20). The vendor's `auth.md` says registration needs a person and there is no client-registration endpoint (0). Total 40.
- ZeroBounce (35): No x402, MPP or L402 (0). Per-credit prices public, from $39 for 2,000 validations (20). Freemium of 100 validations a month for business or premium domains; a card requirement isn't stated, and free webmail addresses don't qualify (15 of 20). A person signs up in a browser (0). 0+20+15+0 = 35.

## Score by category

| Category | Weight | Explorium AgentSource | ZeroBounce | Edge |
| --- | --- | --- | --- | --- |
| Reliability | 16% (20 this run) | 42 | 75 | ZeroBounce +33 |
| Performance | 10%, pending | pending | pending | not scored in this run |
| Schema & documentation | 13% (16.2 this run) | 40 | 54 | ZeroBounce +14 |
| Agent ergonomics | 13% (16.2 this run) | 63 | 69 | ZeroBounce +6 |
| Security & auth | 14% (17.5 this run) | 32 | 65 | ZeroBounce +33 |
| Payments & pricing | 10% (12.5 this run) | 40 | 35 | Explorium AgentSource +5 |
| Task success | 10%, pending | pending | pending | not scored in this run |
| Maintenance & community | 7% (8.8 this run) | 28 | 70 | ZeroBounce +42 |
| Transparency & trust | 7% (8.8 this run) | 61 | 63 | ZeroBounce +2 |
| Negative events | ≤15 | -2 | 0 | |
| **Total** | | **41.5 · E** | **62.4 · B** | |

## Facts side by side

| Fact | Explorium AgentSource | ZeroBounce |
| --- | --- | --- |
| Kind | HTTP API | HTTP API |
| Vendor | Explorium Ltd. | Hertza L.L.C. (ZeroBounce) |
| Hosted endpoint | `https://api.explorium.ai` | `https://api.zerobounce.net/v2` |
| Transports | HTTP, Streamable HTTP, SSE (legacy) | HTTP, stdio |
| Auth | API key | API key |
| Pricing | Pay per use | Pay per use |
| Price for lead enrichment | $0.15 per record | not published |
| x402 | no | no |
| Licence | Proprietary service under the Explorium Terms of Use. The `mcp-explorium` repository of connection files is MIT | Proprietary service under ZeroBounce's terms of use; SDKs and the MCP server are open source |
| Tools exposed | 11 | 0 |
| Read-only variant documented | no | no |
| llms.txt | yes | yes |
| Last release | 2026-09-02 | 2026-10-25 |
| Terms last updated | 2026-06-14 | 2026-05-05 |
| Privacy policy last updated | 2026-06-28 | 2026-06-30 |
| Customer content may train models | not found in the text | not found in the text |
| Terms restrict automated access | yes | not found in the text |
| Terms restrict benchmarking | yes | not found in the text |
| Terms or service can change without notice | yes | yes |
| Arbitration or class-action waiver | not found in the text | yes |

## How the scores have moved

### Explorium AgentSource

- -6.7 on 4 November 2026 (D to E): new evidence, correction
- -0.1 on 28 October 2026: correction
- +0.2 on 27 October 2026: checklist

### ZeroBounce

No score change since it was listed.

## Verdicts

**Explorium AgentSource.** AgentSource v2 has 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, no specification file is linked from the docs, and the vendor's two published price tables disagree.

**ZeroBounce.** ZeroBounce's v2 API verifies emails with detailed status and sub-status codes, publishes per-endpoint limits, a Statuspage with short incidents only in the last 90 days, SOC 2 Type 2 and ISO 27001, and $0.0195 per email at the smallest pack. The documented key travels in the query string, and there is no OpenAPI contract.

## 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

### ZeroBounce

1. Use the regional host (api-us or api-eu) that matches the data, and test with the sandbox addresses, which spend no credits
2. Set `timeout` (3 to 60 seconds); slow mail servers return unknown, which is free to retry later
3. Stay under 80,000 validations per 10 seconds and avoid repeated bad requests, which block the key for an hour
4. Use the bulk file API for large lists instead of looping on /v2/validate
5. Keep the key out of logs; the API takes it only as `api_key` in the URL

## Questions

### Which is better for AI agents, Explorium AgentSource or ZeroBounce?

ZeroBounce scores 62.4 (B) on agent readiness against Explorium AgentSource's 41.5 (E), and leads in 6 of 7 scored categories. Explorium AgentSource leads on payments & pricing.

### Do Explorium AgentSource and ZeroBounce need an API key?

Both need an API key.

### Can an agent call Explorium AgentSource and ZeroBounce without installing anything?

Yes. Explorium AgentSource has a hosted endpoint at https://api.explorium.ai and ZeroBounce at https://api.zerobounce.net/v2.


## For agents

- This comparison as JSON: https://www.anchorterminal.com/compare/explorium-agentsource-vs-zerobounce.json, and with the fewest tokens: https://www.anchorterminal.com/compare/explorium-agentsource-vs-zerobounce.min.md
- Over MCP at https://www.anchorterminal.com/mcp (no key): `compare_tools {"a": "explorium-agentsource", "b": "zerobounce"}`. From a terminal: `anchor compare explorium-agentsource zerobounce`
- Each listing in full: https://www.anchorterminal.com/api/v1/tools/explorium-agentsource.json and https://www.anchorterminal.com/api/v1/tools/zerobounce.json

## Other comparisons with Explorium AgentSource or ZeroBounce

- [Apollo API + MCP vs Explorium AgentSource](https://www.anchorterminal.com/compare/apollo-vs-explorium-agentsource.md)
- [Clay vs Explorium AgentSource](https://www.anchorterminal.com/compare/clay-vs-explorium-agentsource.md)
- [Coresignal API + MCP vs Explorium AgentSource](https://www.anchorterminal.com/compare/coresignal-vs-explorium-agentsource.md)
- [Crustdata API + MCP vs Explorium AgentSource](https://www.anchorterminal.com/compare/crustdata-vs-explorium-agentsource.md)
- [Dievio vs Explorium AgentSource](https://www.anchorterminal.com/compare/dievio-vs-explorium-agentsource.md)
- [Enrich Layer API + MCP vs Explorium AgentSource](https://www.anchorterminal.com/compare/enrich-layer-vs-explorium-agentsource.md)
- [Explorium AgentSource vs FullEnrich API + MCP](https://www.anchorterminal.com/compare/explorium-agentsource-vs-fullenrich.md)
- [Explorium AgentSource vs Fuse MCP](https://www.anchorterminal.com/compare/explorium-agentsource-vs-fuse-mcp.md)
- [Explorium AgentSource vs Gojiberry](https://www.anchorterminal.com/compare/explorium-agentsource-vs-gojiberry.md)
- [Explorium AgentSource vs Hunter API + MCP](https://www.anchorterminal.com/compare/explorium-agentsource-vs-hunter.md)
- [Explorium AgentSource vs LeadMagic API + MCP](https://www.anchorterminal.com/compare/explorium-agentsource-vs-leadmagic.md)
- [Explorium AgentSource vs Lusha API + MCP](https://www.anchorterminal.com/compare/explorium-agentsource-vs-lusha.md)
- [Explorium AgentSource vs People Data Labs](https://www.anchorterminal.com/compare/explorium-agentsource-vs-people-data-labs.md)
- [Explorium AgentSource vs Prospeo API + MCP](https://www.anchorterminal.com/compare/explorium-agentsource-vs-prospeo.md)
- [Explorium AgentSource vs RocketReach API](https://www.anchorterminal.com/compare/explorium-agentsource-vs-rocketreach.md)
- [Explorium AgentSource vs ZoomInfo API + MCP](https://www.anchorterminal.com/compare/explorium-agentsource-vs-zoominfo.md)
- [Apollo API + MCP vs ZeroBounce](https://www.anchorterminal.com/compare/apollo-vs-zerobounce.md)
- [Clay vs ZeroBounce](https://www.anchorterminal.com/compare/clay-vs-zerobounce.md)
- [Clearbit vs Explorium AgentSource](https://www.anchorterminal.com/compare/clearbit-vs-explorium-agentsource.md)
- [Clearbit vs ZeroBounce](https://www.anchorterminal.com/compare/clearbit-vs-zerobounce.md)
- [Coresignal API + MCP vs ZeroBounce](https://www.anchorterminal.com/compare/coresignal-vs-zerobounce.md)
- [Crustdata API + MCP vs ZeroBounce](https://www.anchorterminal.com/compare/crustdata-vs-zerobounce.md)
- [Databar vs Explorium AgentSource](https://www.anchorterminal.com/compare/databar-vs-explorium-agentsource.md)
- [Databar vs ZeroBounce](https://www.anchorterminal.com/compare/databar-vs-zerobounce.md)
- [Dievio vs ZeroBounce](https://www.anchorterminal.com/compare/dievio-vs-zerobounce.md)
- [Dropcontact API + MCP vs Explorium AgentSource](https://www.anchorterminal.com/compare/dropcontact-vs-explorium-agentsource.md)
- [Dropcontact API + MCP vs ZeroBounce](https://www.anchorterminal.com/compare/dropcontact-vs-zerobounce.md)
- [Enrich Layer API + MCP vs ZeroBounce](https://www.anchorterminal.com/compare/enrich-layer-vs-zerobounce.md)
- [Explorium AgentSource vs FullContact](https://www.anchorterminal.com/compare/explorium-agentsource-vs-fullcontact.md)
- [FullContact vs ZeroBounce](https://www.anchorterminal.com/compare/fullcontact-vs-zerobounce.md)
- [FullEnrich API + MCP vs ZeroBounce](https://www.anchorterminal.com/compare/fullenrich-vs-zerobounce.md)
- [Gojiberry vs ZeroBounce](https://www.anchorterminal.com/compare/gojiberry-vs-zerobounce.md)
- [Lusha API + MCP vs ZeroBounce](https://www.anchorterminal.com/compare/lusha-vs-zerobounce.md)
- [People Data Labs vs ZeroBounce](https://www.anchorterminal.com/compare/people-data-labs-vs-zerobounce.md)
- [Prospeo API + MCP vs ZeroBounce](https://www.anchorterminal.com/compare/prospeo-vs-zerobounce.md)
- [ZeroBounce vs ZoomInfo API + MCP](https://www.anchorterminal.com/compare/zerobounce-vs-zoominfo.md)
- [Hunter API + MCP vs ZeroBounce](https://www.anchorterminal.com/compare/hunter-vs-zerobounce.md)
- [Fuse MCP vs ZeroBounce](https://www.anchorterminal.com/compare/fuse-mcp-vs-zerobounce.md)
- [LeadMagic API + MCP vs ZeroBounce](https://www.anchorterminal.com/compare/leadmagic-vs-zerobounce.md)
- [RocketReach API vs ZeroBounce](https://www.anchorterminal.com/compare/rocketreach-vs-zerobounce.md)

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Query this catalogue directly over MCP: https://www.anchorterminal.com/mcp (Streamable HTTP, no key). How: https://www.anchorterminal.com/agents/#mcp