# NoBounce Email Validation (remote · nobounceapi.com)

Real-time single and bulk email validation (syntax, MX, 5,000+ disposable domains, SMTP).

- Trust score: 70/100 (medium)
- Change this week: +3
- Registry status: active
- Liveness: live
- Owner verified: no
- Last scored: 2026-11-05

## Components

- remote · `nobounceapi.com`: 70/100 (this document), [markdown](https://verifymcp.io/servers/notprathap-nobounce-mcp/nobounceapi.md), [page](https://verifymcp.io/servers/notprathap-nobounce-mcp/nobounceapi)

## Channel facts

- Endpoint: `https://nobounceapi.com/mcp`
- Transports: `streamable-http`
- Auth: `none`
- Version: `1.0.0`

## Trust breakdown

How this component scores in each security and reliability category. Every signal is checked automatically against the live server, and we only credit what we can confirm. Scores are 0–100 per category. Scoring method: https://verifymcp.io/docs/scoring (what has changed: https://verifymcp.io/docs/scoring/changelog)

Scored 2026-11-05.

- **Endpoint Security**: 57/100
  - The endpoint's TLS certificate is valid, in date, and uses a strong key.
  - Authorisation not fully verified: no authorisation is required to call this server, and 2 tool(s) never declared a destructiveHint. The MCP spec treats an absent hint as destructive by default, so we cannot call this surface safe.
  - HTTPS is enforced; there's no plaintext access path.
  - HSTS check failed: the Strict-Transport-Security header is absent.
  - DNSSEC check failed: this domain isn't protected by DNSSEC.
- **Transport & Reachability**: 100/100
  - Verified streamable-http transport via a live MCP handshake.
- **Schema Quality & AI Usability**: 74/100
  - AI-judged instruction clarity (good).
  - Tool/resource definitions use about 182 tokens (~91/item across 2 items; 2 tools + 0 resources), lean.
  - Usage-examples check failed: none of the tools include examples.
- **Stability & Change Management**: 63/100
  - Stability observed for 19 of 30 days with no destabilising changes; credit accrues until the full window elapses.
- **Tool Coverage**: 100/100
  - 100% of tools have a non-trivial description (not blank, and not just the tool's name).
  - 100% of tool parameters carry a description.
- **Tool Safety**: 100/100
  - No prompt-injection markers were found in the server instructions, tool names or descriptions we captured.
  - We read all 2 captured tool definition(s), and no name or description among them implies an irreversible operation.
  - An AI judge read all 2 captured unit(s) of tool text and found none that tries to manipulate the model reading it.
- **Capabilities**: 20/100
  - Spec-recency check failed: implements MCP spec 2024-11-05; the latest is 2026-07-28.

## Install

### How do I install the NoBounce Email Validation MCP server?

NoBounce Email Validation is a hosted endpoint at https://nobounceapi.com/mcp, so there is nothing to install locally. Ready-made configuration for Claude, Cursor, VS Code, Codex and 5 more is on this page, copied from each client's own documentation.

### Claude

```bash
claude mcp add --transport http notprathap-nobounce-mcp 'https://nobounceapi.com/mcp'
```

### Cursor

```json
{
  "mcpServers": {
    "notprathap-nobounce-mcp": {
      "url": "https://nobounceapi.com/mcp"
    }
  }
}
```

### VS Code

```json
{
  "servers": {
    "notprathap-nobounce-mcp": {
      "type": "http",
      "url": "https://nobounceapi.com/mcp"
    }
  }
}
```

### Codex

```toml
[mcp_servers.notprathap-nobounce-mcp]
url = "https://nobounceapi.com/mcp"
```

### opencode

```json
{
  "$schema": "https://opencode.ai/config.json",
  "mcp": {
    "notprathap-nobounce-mcp": {
      "type": "remote",
      "url": "https://nobounceapi.com/mcp",
      "enabled": true
    }
  }
}
```

### OpenClaw

```bash
openclaw mcp add notprathap-nobounce-mcp --url 'https://nobounceapi.com/mcp' --transport streamable-http
```

### Hermes

```yaml
mcp_servers:
  notprathap-nobounce-mcp:
    url: "https://nobounceapi.com/mcp"
```

### Netclaw

```json
{
  "McpServers": {
    "notprathap-nobounce-mcp": {
      "Transport": "http",
      "Url": "https://nobounceapi.com/mcp"
    }
  }
}
```

### Vellum

```bash
assistant mcp add notprathap-nobounce-mcp -t streamable-http -u 'https://nobounceapi.com/mcp'
```

### Other

```json
{
  "mcpServers": {
    "notprathap-nobounce-mcp": {
      "type": "http",
      "url": "https://nobounceapi.com/mcp"
    }
  }
}
```

The mcpServers block is a cross-client convention. Remote transports vary, so check your client's docs.

## Changelog

Every change recorded for this component, newest first. Days that predate change tracking, or that we cannot explain, say so: "we were watching and nothing happened" and "we were not watching" are different claims.

### 2026-11-05 (score 70, +1)

No change was recorded against any check on this day. Stability & Change Management went from 60 to 63. That category is still filling its 30-day observation window: 18 days of observed history at the previous scan, 19 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-11-03 (score 69, +1)

No change was recorded against any check on this day. Stability & Change Management went from 53 to 57. That category is still filling its 30-day observation window: 16 days of observed history at the previous scan, 17 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-10-31 (score 68, +1)

No change was recorded against any check on this day. Stability & Change Management went from 43 to 47. That category is still filling its 30-day observation window: 13 days of observed history at the previous scan, 14 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-10-29 (score 67, +1)

No change was recorded against any check on this day. Stability & Change Management went from 37 to 40. That category is still filling its 30-day observation window: 11 days of observed history at the previous scan, 12 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-10-27 (score 66, +1)

No change was recorded against any check on this day. Stability & Change Management went from 30 to 33. That category is still filling its 30-day observation window: 9 days of observed history at the previous scan, 10 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-10-25 (score 65, +1)

No change was recorded against any check on this day. Stability & Change Management went from 23 to 27. That category is still filling its 30-day observation window: 7 days of observed history at the previous scan, 8 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-10-23 (score 64, +1)

No change was recorded against any check on this day. Stability & Change Management went from 17 to 20. That category is still filling its 30-day observation window: 5 days of observed history at the previous scan, 6 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-10-21 (score 63, +1)

No change was recorded against any check on this day. Stability & Change Management went from 10 to 13. That category is still filling its 30-day observation window: 3 days of observed history at the previous scan, 4 at this one. The score rises as the window fills, whether or not the server changes.

## MCP tools (2)

### `validate_email` (~93 tokens)

Validate a single email address in real time using NoBounce API. Checks RFC 5322 syntax, DNS MX records, 5,000+ disposable providers, role accounts, free webmail providers, typo suggestions, and optional SMTP handshake.

Input parameters:

- `email` (string, required): The email address to validate (e.g., contact@github.com)
- `smtp_check` (boolean): Perform deep SMTP mailbox handshake (default: false)

### `validate_emails_bulk` (~89 tokens)

Validate a batch of up to 1,000 email addresses in a single call using NoBounce API. Returns per-email validation results plus summary counts (valid, invalid, disposable, catch_all, unknown).

Input parameters:

- `emails` (array, required): List of email addresses to validate (up to 1,000 emails)
- `smtp_check` (boolean): Perform deep SMTP mailbox handshake (default: false)

## Diagnostics

Captured diagnostic sections: TLS, DNSSEC, Authorisation, Transports. The full working is on the page: https://verifymcp.io/servers/notprathap-nobounce-mcp/nobounceapi#diagnostics

## Score history

- 2026-11-05: 70
- 2026-11-04: 69
- 2026-11-03: 69
- 2026-11-02: 68
- 2026-11-01: 68
- 2026-10-31: 68
- 2026-10-30: 67
- 2026-10-29: 67
- 2026-10-28: 66
- 2026-10-27: 66
- 2026-10-26: 65
- 2026-10-25: 65
- 2026-10-24: 64
- 2026-10-23: 64
- 2026-10-22: 63
- 2026-10-21: 63
- 2026-10-20: 62
- 2026-10-19: 62
- 2026-10-18: 61
- 2026-10-17: 61
- 2026-10-16: 23

## Common questions

### What is the NoBounce Email Validation MCP server?

NoBounce Email Validation is an MCP server listed in the public MCP registry as io.github.notprathap/nobounce-mcp. Real-time single and bulk email validation (syntax, MX, 5,000+ disposable domains, SMTP). This page covers its hosted endpoint (https://nobounceapi.com/mcp).

### Is the NoBounce Email Validation MCP server safe to use?

NoBounce Email Validation scores 70 out of 100 on VerifyMCP. That is a record of what we were able to check automatically, not an endorsement. The category breakdown on this page shows every signal behind the number, including the ones we could not confirm.

### What tools does the NoBounce Email Validation MCP server expose?

NoBounce Email Validation exposes 2 tools: validate_email, validate_emails_bulk. Their descriptions and schemas cost roughly 182 tokens of context every time the server is loaded.

### Does the NoBounce Email Validation MCP server require authentication?

No. We connected to NoBounce Email Validation without credentials and it answered, so anything it exposes is reachable by anyone who knows the address.

### Is the NoBounce Email Validation MCP server still maintained?

NoBounce Email Validation is still listed as active in the MCP registry. We last reached this channel on 5 November 2026. Those dates come from our own scans of the registry and the channel itself, not from anything the publisher announced.

### What did VerifyMCP test on the NoBounce Email Validation MCP server?

VerifyMCP ran 12 checks on NoBounce Email Validation, covering TLS certificate, HTTPS, HSTS header, DNSSEC and 8 more. One item could not be completed, a gap on our side rather than a finding about NoBounce Email Validation: Authorization. Supply Chain Security and Provenance & Transparency do not apply to a hosted endpoint, so they were not tested. The score does not measure everything, and the scoring documentation lists what it leaves out.

## Links

- Remote endpoint: https://nobounceapi.com/mcp
- Authorisation metadata: https://nobounceapi.com/.well-known/oauth-protected-resource/mcp
- Repository: https://github.com/notprathap/nobounce-mcp
- Changelog RSS feed: https://verifymcp.io/servers/notprathap-nobounce-mcp/nobounceapi.xml
- Changelog JSON feed: https://verifymcp.io/servers/notprathap-nobounce-mcp/nobounceapi/changelog.json
- Trust report (JSON): https://verifymcp.io/servers/notprathap-nobounce-mcp/nobounceapi.json
- HTML version of this page: https://verifymcp.io/servers/notprathap-nobounce-mcp/nobounceapi