# Fuse MCP vs ZeroBounce

> ZeroBounce scores 62.4 (B) to Fuse MCP's 44.3 (E) for email verification. Prices, MCP, x402, uptime and agent notes side by side.

- Canonical: https://www.anchorterminal.com/compare/fuse-mcp-vs-zerobounce
- Markdown: https://www.anchorterminal.com/compare/fuse-mcp-vs-zerobounce.md (~4,800 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 Fuse MCP's 44.3 (E), and leads in every scored category. Both do email verification.

- Fuse MCP: grade E, 44.3/100, rank #1212 of 1486. Markdown https://www.anchorterminal.com/tools/fuse-mcp.md · JSON https://www.anchorterminal.com/api/v1/tools/fuse-mcp.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

### Fuse MCP (E)

Good for: Suited to a salesperson or founder who wants an assistant to build prospect lists, enrich them and run email and LinkedIn outreach inside one Fuse account.

Watch for: The only OAuth scope is `mcp:tools`, so a connection can do everything its user can, including sending email and LinkedIn messages

### ZeroBounce (B)

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

Ahead on:
- Reliability, 75 against 40
- Agent ergonomics, 69 against 57
- Security & auth, 65 against 43
- Payments & pricing, 35 against 30
- Maintenance & community, 70 against 35
- Transparency & trust, 63 against 52

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

### Reliability: ZeroBounce +35

- Fuse MCP (40): Graded as a hosted service. FuseAI's terms bar automated systems or scripts from extracting content from the Services, which they define to include the website, so every fuseai.com page keeps its 8 October reading, not re-read on 4 November 2026. No status page is linked from the site, the docs or the sitemap (0). No readable incident history (5). MCP limits are published at 60 requests a minute and 5,000 a day per user (15). The server answers 429 with `RATE_LIMIT_EXCEEDED` and the docs say to back off and retry. No `Retry-After` is documented for the MCP server and there are no idempotency keys, so backoff guidance alone (10). No SLA found (0). The server carries no beta or preview label (10). 0 + 5 + 15 + 10 + 0 + 10 = 40.
- 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.

### Maintenance & community: ZeroBounce +35

- Fuse MCP (35): Readings are per the 8 October check, not re-read on 4 November 2026. The tool reference is dated 7 October 2026 and records the October 2026 rebuild of the tool list, within 30 days today (30); it drops to 20 after 6 November unless a newer dated change appears. No changelog or release notes found, so three dated entries in 90 days could not be shown (0). No public changelog or issue tracker. Support is by email at support@fuseai.com, not tested (5 of 15). No readable registry page names the server and no official SDK was found (0). No package to assess (0 of 10). 30 + 0 + 5 + 0 + 0 = 35.
- 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.

### Security & auth: ZeroBounce +22

- Fuse MCP (43): Readings are per the 8 October check, not re-read on 4 November 2026. OAuth authorisation code with PKCE and dynamic client registration, one-hour access tokens and rotating refresh tokens. The only scope is `mcp:tools`, so every connection has the user's full permissions (22 of 30). There is no read-only mode. Destructive tool descriptions tell the model to get the user's confirmation, but the server enforces none of this and changes apply at once. Billing, API key and team-removal tools are left out (8 of 20). Tools return inbox email, LinkedIn messages and scraped web pages, and the only guidance found is to connect trusted clients and keep approval prompts on (4 of 15). Audit logging is listed for Enterprise and a credit usage ledger exists, with no per-call log for MCP documented (4 of 15). Programme 7 to 5. The home page lists SOC 2 Type I and CASA Tier 2 with no report, trust centre, security.txt, disclosure policy or bug bounty found, and a bare certification claim with no report or reporting route scores 5, as for zamp. 22 + 8 + 4 + 4 + 5 = 43.
- 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.

### Agent ergonomics: ZeroBounce +12

- Fuse MCP (57): Readings are per the 8 October check, not re-read on 4 November 2026. 290 tools and about half a megabyte of definitions, with no toolsets, dynamic loading or read-only subset. The docs warn that some clients pass only the first 40 tools (5 of 25). List reads return a `data` array with `pagination`, searches return a scroll token or cursor, and tools take limits and filters (18 of 20). Rejected calls set `isError` and return codes such as `TOOL_ARGUMENT_VALIDATION_FAILED` with the missing field named. Other failures are short plain text (15 of 20). The docs say every tool carries `readOnlyHint` or `destructiveHint`, which we could not read from the server. No idempotency keys, and sends are not marked destructive (14 of 20). No official SDK found, and most changes need an id looked up first (5 of 15). 5 + 18 + 15 + 14 + 5 = 57.
- 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.

### Transparency & trust: ZeroBounce +11

- Fuse MCP (52): Readings are per the 8 October check, not re-read on 4 November 2026. Closed service with published terms of service, last updated 1 July 2026 (unchanged on 4 November), naming FuseAI, LLC (15). The privacy policy of the same date is general. Retention is as long as necessary with no periods, and no DPA or subprocessor list was found (10 of 30). No deprecation policy. The docs record the October 2026 removal of the earlier tools and that the earlier server URL keeps working (5 of 20). The docs name 39 external data providers. Hosting, data locations and subprocessors are not disclosed (6 of 20). 15 + 10 + 5 + 6 = 36.
- ZeroBounce (63): Closed service under terms naming Hertza L.L.C. (ZeroBounce) of Nevada; SDKs and MCP server open source (15 of 30). The data protection page says uploaded data is never kept more than 30 days, the privacy policy of 30 June 2026 keeps account data 'as long as needed', and EU and UK DPAs are published (22 of 30). An API migration page, with no dated deprecation policy (6 of 20). A sub-processor list naming each provider and the data exchanged (16 of 20). 15+22+6+16 = 59.

### Payments & pricing: ZeroBounce +5

- Fuse MCP (30): Readings are per the 8 October check, not re-read on 4 November 2026. No x402, MPP or L402 (0). Plan prices and the credit cost of each action are public, and `get_credit_prices` returns them. Top-up prices are shown only in the app and the Free allowance is stated two ways (15 of 20). A Free plan exists at $0. The Solo plan card is where MCP is listed, and we could not confirm that Free includes it or that signup needs no card (15 of 20). A person signs in through a browser to approve each connection (0). 0 + 15 + 15 + 0 = 30.
- 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 | Fuse MCP | ZeroBounce | Edge |
| --- | --- | --- | --- | --- |
| Reliability | 16% (20 this run) | 40 | 75 | ZeroBounce +35 |
| Performance | 10%, pending | pending | pending | not scored in this run |
| Schema & documentation | 13% (16.2 this run) | 50 | 54 | ZeroBounce +4 |
| Agent ergonomics | 13% (16.2 this run) | 57 | 69 | ZeroBounce +12 |
| Security & auth | 14% (17.5 this run) | 43 | 65 | ZeroBounce +22 |
| Payments & pricing | 10% (12.5 this run) | 30 | 35 | ZeroBounce +5 |
| Task success | 10%, pending | pending | pending | not scored in this run |
| Maintenance & community | 7% (8.8 this run) | 35 | 70 | ZeroBounce +35 |
| Transparency & trust | 7% (8.8 this run) | 52 | 63 | ZeroBounce +11 |
| Negative events | ≤15 | 0 | 0 | |
| **Total** | | **44.3 · E** | **62.4 · B** | |

## Facts side by side

| Fact | Fuse MCP | ZeroBounce |
| --- | --- | --- |
| Kind | MCP server | HTTP API |
| Vendor | FuseAI, LLC | Hertza L.L.C. (ZeroBounce) |
| Hosted endpoint | `https://mcp.fuseai.com` | `https://api.zerobounce.net/v2` |
| Transports | Streamable HTTP | HTTP, stdio |
| Auth | OAuth | API key |
| Pricing | Freemium | Pay per use |
| x402 | no | no |
| Licence | Proprietary hosted service under FuseAI's terms of service. No public source repository found | Proprietary service under ZeroBounce's terms of use; SDKs and the MCP server are open source |
| Tools exposed | 290 | 0 |
| Read-only variant documented | yes | no |
| llms.txt | yes | yes |
| Last release | 2026-10-07 | 2026-10-25 |
| Terms last updated | 2026-07-01 | 2026-05-05 |
| Privacy policy last updated | 2026-07-01 | 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 | not found in the text | not found in the text |
| Terms or service can change without notice | not found in the text | yes |
| Arbitration or class-action waiver | yes | yes |

## How the scores have moved

### Fuse MCP

- -3.9 on 4 November 2026 (D to E): correction
- +0.3 on 27 October 2026: checklist

### ZeroBounce

No score change since it was listed.

## Verdicts

**Fuse MCP.** The server documents 290 tools with read-only and destructive annotations, OAuth with PKCE and dynamic client registration, and published limits of 60 requests a minute. The single `mcp:tools` scope grants everything the user can do, sends happen at once with no undo, and no status page, changelog or security contact was found.

**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

### Fuse MCP

1. Keep the client's approval prompt on for every tool that is not read-only. Sends, CRM pushes and Slack posts run at once with no undo
2. Launch a campaign only on an explicit request. Creating one makes a draft, and `update_campaign_status_tool` starts real outreach
3. Call `get_credits_balance` and `get_credit_prices` first. Every call needs at least 100 credits, and searches cost 2 credits a result
4. Resolve filter values with `lookup_filter_values` or `get_company_search_enums` before `search_people` or `search_companies`
5. Start long work with `deep_research_start`, then poll `deep_research_status`. A tool call has 60 seconds, and runs take 5 to 20 minutes

### 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, Fuse MCP or ZeroBounce?

ZeroBounce scores 62.4 (B) on agent readiness against Fuse MCP's 44.3 (E), and leads in every scored category.

### Do Fuse MCP and ZeroBounce need an API key?

Fuse MCP uses an OAuth sign-in. ZeroBounce needs an API key.

### Can an agent call Fuse MCP and ZeroBounce without installing anything?

Yes. Fuse MCP has a hosted endpoint at https://mcp.fuseai.com and ZeroBounce at https://api.zerobounce.net/v2.


## For agents

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

## Other comparisons with Fuse MCP or ZeroBounce

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