# io.github.mrfentmen/neverbounce-mcp (npm · neverbounce-mcp)

NeverBounce email verification: single checks, bulk jobs and job results.

- Trust score: 68/100 (medium)
- Change this week: +4
- Registry status: active
- Liveness: live
- Owner verified: no
- Last scored: 2026-11-05

## Components

- npm · `neverbounce-mcp`: 68/100 (this document), [markdown](https://verifymcp.io/servers/mrfentmen-neverbounce-mcp/neverbounce-mcp.md), [page](https://verifymcp.io/servers/mrfentmen-neverbounce-mcp/neverbounce-mcp)

## Channel facts

- Registry: `npm`
- Package: `neverbounce-mcp`
- Version: `1.0.0`
- Transport: `stdio`

## Trust breakdown

How this component scores in each security and reliability category. Every signal is checked automatically from public evidence about the published package, including repeated runs of it in an isolated sandbox, 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.

- **Supply Chain Security**: 98/100
  - No malware found by supply-chain analysis.
  - No known CVEs affecting this package version or its production dependencies.
  - No install/post-install scripts declared.
  - 30 of 92 dependencies flagged as unhealthy.
- **Provenance & Transparency**: 45/100
  - Source repository is publicly reachable at the declared URL.
  - Provenance check failed: no build-provenance attestation is published.
  - Clear OSI-approved license (MIT).
  - Actively maintained (last published 9 days ago).
  - Disclosure check failed: no security disclosure policy was found in the source repository.
- **Schema Quality & AI Usability**: 61/100
  - AI-judged instruction clarity (fair).
  - Tool/resource definitions use about 600 tokens (~50/item across 12 items; 12 tools + 0 resources), lean.
  - Usage-examples check failed: none of the tools include examples.
- **Stability & Change Management**: 30/100
  - Stability observed for 9 of 30 days with no destabilising changes; credit accrues until the full window elapses.
- **Tool Coverage**: 74/100
  - 100% of tools have a non-trivial description (not blank, and not just the tool's name).
  - 23% of tool parameters carry a description.
- **Tool Safety**: 75/100
  - No prompt-injection markers were found in the server instructions, tool names or descriptions we captured.
  - 0 of 1 tool(s) whose name or description implies an irreversible operation declare an MCP destructiveHint annotation; "nb_job_delete" implies "delete" and declares no destructiveHint at all, which the MCP spec reads as destructive by default.
  - An AI judge read all 12 captured unit(s) of tool text and found none that tries to manipulate the model reading it.
- **Capabilities**: 100/100
  - Implements a supported MCP spec version (2025-11-25); the latest is 2026-07-28.

## Install

### How do I install the io.github.mrfentmen/neverbounce-mcp server?

io.github.mrfentmen/neverbounce-mcp runs locally as an npm package, launched with npx -y neverbounce-mcp. 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 mrfentmen-neverbounce-mcp -- npx -y neverbounce-mcp
```

### Cursor

```json
{
  "mcpServers": {
    "mrfentmen-neverbounce-mcp": {
      "command": "npx",
      "args": [
        "-y",
        "neverbounce-mcp"
      ]
    }
  }
}
```

### VS Code

```json
{
  "servers": {
    "mrfentmen-neverbounce-mcp": {
      "command": "npx",
      "args": [
        "-y",
        "neverbounce-mcp"
      ]
    }
  }
}
```

### Codex

```bash
codex mcp add mrfentmen-neverbounce-mcp -- npx -y neverbounce-mcp
```

### opencode

```json
{
  "$schema": "https://opencode.ai/config.json",
  "mcp": {
    "mrfentmen-neverbounce-mcp": {
      "type": "local",
      "command": [
        "npx",
        "-y",
        "neverbounce-mcp"
      ],
      "enabled": true
    }
  }
}
```

### OpenClaw

```bash
openclaw mcp add mrfentmen-neverbounce-mcp --command npx --arg -y --arg neverbounce-mcp
```

### Hermes

```yaml
mcp_servers:
  mrfentmen-neverbounce-mcp:
    command: "npx"
    args: ["-y", "neverbounce-mcp"]
```

### Netclaw

```json
{
  "McpServers": {
    "mrfentmen-neverbounce-mcp": {
      "Transport": "stdio",
      "Command": "npx",
      "Arguments": [
        "-y",
        "neverbounce-mcp"
      ]
    }
  }
}
```

### Vellum

```bash
assistant mcp add mrfentmen-neverbounce-mcp -t stdio -c npx -a -y neverbounce-mcp
```

### Other

```json
{
  "mcpServers": {
    "mrfentmen-neverbounce-mcp": {
      "command": "npx",
      "args": [
        "-y",
        "neverbounce-mcp"
      ]
    }
  }
}
```

## 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.

### 2026-11-04 (score 68, +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.

### 2026-11-03 (score 67, +3)

- [functional improvement] Stability: unverified → 0.23

### 2026-10-28 (score 64, +15)

- [security improvement] Malware scan: unverified → pass

### 2026-10-27 (score 49)

First indexed and scored.

## MCP tools (12)

### `nb_account_info` (~26 tokens)

Raw NeverBounce account envelope: status, verification credits remaining, monthly usage and limit.

### `nb_account_usage` (~23 tokens)

Just the credit figures: credits remaining, monthly usage, monthly limit.

### `nb_verify_email` (~65 tokens)

Verify ONE email address: result (valid / invalid / disposable / catchall / unknown), flags (free provider, role account, disposable host, spamtrap, bounce), and a suggested correction if any.

Input parameters:

- `email` (string, required)
- `timeout` (integer): seconds

### `nb_verify_email_strict` (~71 tokens)

The same verification plus a verdict line computed here: safe (send), risky (catchall/disposable - judge first), dead (do not send), unknown (retry later). For deciding whether an agent should send at all.

Input parameters:

- `email` (string, required)
- `timeout` (integer): seconds

### `nb_poe_confirm` (~55 tokens)

Confirm a Proof of Email (POE) token: pairs the transaction_id and token issued by the POE widget with the original single-check transaction.

Input parameters:

- `token` (string, required)
- `transaction_id` (string, required)

### `nb_job_create` (~106 tokens)

Create a bulk verification job from an email list file or folder that was already uploaded through the NeverBounce dashboard. auto_parse defaults to true; run_sample optionally verifies a sample first.

Input parameters:

- `auto_parse` (boolean)
- `email_filename` (string): file name uploaded via the dashboard
- `email_list_folder` (string): folder name uploaded via the dashboard
- `job_name` (string)
- `run_sample` (boolean): verify a small sample before the full run

### `nb_job_start` (~27 tokens)

Start a created (parsed) bulk verification job.

Input parameters:

- `job_id` (string, required)

### `nb_job_status` (~26 tokens)

Poll the status of a bulk verification job.

Input parameters:

- `job_id` (string, required)

### `nb_job_results` (~56 tokens)

Page through a finished job's per-email results: each row is an email with its verification result and flags.

Input parameters:

- `items_per_page` (integer)
- `job_id` (string, required)
- `start_page` (integer)

### `nb_job_results_summary` (~74 tokens)

One page of a job's results reduced to a per-result tally (valid/invalid/...) plus the query_info totals. For a quick health read of a finished job without pulling every row.

Input parameters:

- `items_per_page` (integer)
- `job_id` (string, required)
- `start_page` (integer)

### `nb_job_download` (~41 tokens)

Get the download payload for a finished job (file_format: json or csv).

Input parameters:

- `file_format` (string)
- `job_id` (string, required)

### `nb_job_delete` (~30 tokens)

Delete a bulk verification job (destructive for that job only).

Input parameters:

- `job_id` (string, required)

## Diagnostics

Captured diagnostic sections: Provenance, Dependencies. The full working is on the page: https://verifymcp.io/servers/mrfentmen-neverbounce-mcp/neverbounce-mcp#diagnostics

## Score history

- 2026-11-05: 68
- 2026-11-04: 68
- 2026-11-03: 67
- 2026-11-02: 64
- 2026-11-01: 64
- 2026-10-31: 64
- 2026-10-30: 64
- 2026-10-29: 64
- 2026-10-28: 64
- 2026-10-27: 49

## Common questions

### What is the io.github.mrfentmen/neverbounce-mcp server?

io.github.mrfentmen/neverbounce-mcp is listed in the public MCP registry as io.github.mrfentmen/neverbounce-mcp. NeverBounce email verification: single checks, bulk jobs and job results. This page covers its npm package (neverbounce-mcp).

### Is the io.github.mrfentmen/neverbounce-mcp server safe to use?

io.github.mrfentmen/neverbounce-mcp scores 68 out of 100 on VerifyMCP. We found no known CVEs affecting it as of 5 November 2026. It declares no install or post-install scripts. 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 io.github.mrfentmen/neverbounce-mcp server expose?

io.github.mrfentmen/neverbounce-mcp exposes 12 tools: nb_account_info, nb_account_usage, nb_verify_email, nb_verify_email_strict, nb_poe_confirm, and 7 more. Their descriptions and schemas cost roughly 600 tokens of context every time the server is loaded.

### Is the io.github.mrfentmen/neverbounce-mcp server still maintained?

io.github.mrfentmen/neverbounce-mcp 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 licence is the io.github.mrfentmen/neverbounce-mcp server under?

io.github.mrfentmen/neverbounce-mcp declares the MIT licence, which is OSI-approved. That covers the source only, and says nothing about the cost of any service it calls.

## Links

- npm package: https://www.npmjs.com/package/neverbounce-mcp
- Socket report: https://socket.dev/npm/package/neverbounce-mcp
- Repository: https://github.com/mrfentmen/awesome-servers
- Changelog RSS feed: https://verifymcp.io/servers/mrfentmen-neverbounce-mcp/neverbounce-mcp.xml
- Changelog JSON feed: https://verifymcp.io/servers/mrfentmen-neverbounce-mcp/neverbounce-mcp.json
- HTML version of this page: https://verifymcp.io/servers/mrfentmen-neverbounce-mcp/neverbounce-mcp