# Postmark (npm · @pipeworx/mcp-postmark)

Postmark MCP.

- Trust score: 79/100 (medium)
- Change this week: +3
- Registry status: active
- Liveness: live
- Owner verified: no
- Last scored: 2026-11-05

## Components

- remote · `gateway.pipeworx.io`: 77/100, [markdown](https://verifymcp.io/servers/pipeworx-io-postmark/postmark-mcp.md), [page](https://verifymcp.io/servers/pipeworx-io-postmark/postmark-mcp)
- npm · `@pipeworx/mcp-postmark`: 79/100 (this document), [markdown](https://verifymcp.io/servers/pipeworx-io-postmark/pipeworx-mcp-postmark.md), [page](https://verifymcp.io/servers/pipeworx-io-postmark/pipeworx-mcp-postmark)

## Channel facts

- Registry: `npm`
- Package: `@pipeworx/mcp-postmark`
- Version: `0.2.1`
- 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**: 100/100
  - No malware found by supply-chain analysis.
  - No known CVEs affecting this package version or its production dependencies.
  - No install/post-install scripts declared.
  - No production dependencies, so there is no dependency health to assess.
- **Provenance & Transparency**: 97/100
  - Source repository is publicly reachable at the declared URL.
  - Cryptographically verified build provenance (signed, bound to pipeworx-io/mcp-postmark).
  - Clear OSI-approved license (MIT).
  - Actively maintained (last published 0 days ago).
  - Disclosure check failed: no security disclosure policy was found in the source repository.
- **Schema Quality & AI Usability**: 69/100
  - AI-judged instruction clarity (good).
  - Tool/resource definitions use about 631 tokens (~63/item across 10 items; 10 tools + 0 resources), lean.
  - Usage-examples check failed: none of the tools include examples.
- **Stability & Change Management**: 23/100
  - Stability observed for 7 of 30 days with no destabilising changes; credit accrues until the full window elapses.
- **Tool Coverage**: 67/100
  - 100% of tools have a non-trivial description (not blank, and not just the tool's name).
  - 0% 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 2 tool(s) whose name or description implies an irreversible operation declare an MCP destructiveHint annotation; "send" implies "send" and declares no destructiveHint at all, which the MCP spec reads as destructive by default.
  - An AI judge read all 11 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 Postmark MCP server?

Postmark runs locally as an npm package, launched with npx -y @pipeworx/mcp-postmark. 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 pipeworx-io-postmark -- npx -y @pipeworx/mcp-postmark
```

### Cursor

```json
{
  "mcpServers": {
    "pipeworx-io-postmark": {
      "command": "npx",
      "args": [
        "-y",
        "@pipeworx/mcp-postmark"
      ]
    }
  }
}
```

### VS Code

```json
{
  "servers": {
    "pipeworx-io-postmark": {
      "command": "npx",
      "args": [
        "-y",
        "@pipeworx/mcp-postmark"
      ]
    }
  }
}
```

### Codex

```bash
codex mcp add pipeworx-io-postmark -- npx -y @pipeworx/mcp-postmark
```

### opencode

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

### OpenClaw

```bash
openclaw mcp add pipeworx-io-postmark --command npx --arg -y --arg @pipeworx/mcp-postmark
```

### Hermes

```yaml
mcp_servers:
  pipeworx-io-postmark:
    command: "npx"
    args: ["-y", "@pipeworx/mcp-postmark"]
```

### Netclaw

```json
{
  "McpServers": {
    "pipeworx-io-postmark": {
      "Transport": "stdio",
      "Command": "npx",
      "Arguments": [
        "-y",
        "@pipeworx/mcp-postmark"
      ]
    }
  }
}
```

### Vellum

```bash
assistant mcp add pipeworx-io-postmark -t stdio -c npx -a -y @pipeworx/mcp-postmark
```

### Other

```json
{
  "mcpServers": {
    "pipeworx-io-postmark": {
      "command": "npx",
      "args": [
        "-y",
        "@pipeworx/mcp-postmark"
      ]
    }
  }
}
```

## 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 79, +1)

No change was recorded against any check on this day. Stability & Change Management went from 20 to 23. That category is still filling its 30-day observation window: 6 days of observed history at the previous scan, 7 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-11-04 (score 78, +2)

- [security regression] Tool safety: pass → unverified
- [security] Stability: Stability not yet verified: we do not have a sandbox capture of the MCP schema this version of the package serves yet.
- [functional regression] Capabilities: pass → unverified
- [functional regression] Tool coverage: 100 → unverified
- [functional improvement] Stability: unverified → 0.20
- [functional] First check of Schema quality: unverified
- [functional] Package version: 0.2.0 → 0.2.1

### 2026-10-30 (score 76, 0)

- [functional regression] Security disclosure: unverified → fail

### 2026-10-29 (score 76)

First indexed and scored.

## MCP tools (10)

### `send` (~199 tokens)

Send one transactional email through the Postmark delivery API (api.postmarkapp.com/email) using a Postmark server token. Takes from, to, subject, HTML and text bodies, cc, bcc, reply-to, custom headers, tag, open and link tracking flags, and message stream; returns the Postmark MessageID, submitted-at timestamp, recipient, and error code. Use it to deliver a receipt, password reset, alert, or notification message.

Input parameters:

- `bcc` (string)
- `cc` (string)
- `from` (string, required)
- `headers` (array)
- `htmlbody` (string)
- `messagestream` (string)
- `replyto` (string)
- `subject` (string)
- `tag` (string)
- `textbody` (string)
- `to` (string, required)
- `trackLinks` (string)
- `trackopens` (boolean)

### `send_batch` (~111 tokens)

Send a batch of up to 500 transactional emails in one call to the Postmark delivery API (api.postmarkapp.com/email/batch), passing an array of messages in Postmark field form (From, To, Subject, HtmlBody, TextBody, Tag, MessageStream) and a Postmark server token. Returns one result per message with its MessageID, recipient, and error code. Use it for bulk receipts, digests, or notification sends through Postmark.

Input parameters:

- `emails` (array, required)

### `delivery_stats` (~13 tokens)

Server-level delivery stats.

### `messages_outbound` (~44 tokens)

List outbound messages sent through the Postmark server with optional filters (recipient, from, tag, status, fromdate, todate); returns message summaries with status and timestamps.

### `message_outbound_detail` (~22 tokens)

Single outbound detail.

Input parameters:

- `messageId` (string, required)

### `message_outbound_dump` (~45 tokens)

Retrieve the raw MIME source (full email dump) for a sent outbound message by messageId; useful for debugging encoding or header issues.

Input parameters:

- `messageId` (string, required)

### `bounces` (~45 tokens)

List bounced email records from the Postmark server with optional filters (type, inactive, emailFilter, tag, fromdate, todate); returns bounce type, recipient, and timestamp.

### `bounce` (~42 tokens)

Fetch full details for a single Postmark bounce record by numeric id, including bounce type, recipient email, description, and raw bounce content.

Input parameters:

- `id` (string, required)

### `bounce_activate` (~22 tokens)

Re-activate a bounced address.

Input parameters:

- `id` (string, required)

### `server` (~36 tokens)

Fetch configuration and metadata for the current Postmark server, including name, color, delivery settings, bounce/spam threshold, and message stream settings.

## Diagnostics

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

## Score history

- 2026-11-05: 79
- 2026-11-04: 78
- 2026-11-03: 76
- 2026-11-02: 76
- 2026-11-01: 76
- 2026-10-31: 76
- 2026-10-30: 76
- 2026-10-29: 76

## Common questions

### What is the Postmark MCP server?

Postmark is an MCP server listed in the public MCP registry as io.github.pipeworx-io/postmark. Postmark MCP. This page covers its npm package (@pipeworx/mcp-postmark).

### Is the Postmark MCP server safe to use?

Postmark scores 79 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. Its build provenance is signed and verified. 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 Postmark MCP server expose?

Postmark exposes 10 tools: send, send_batch, delivery_stats, messages_outbound, message_outbound_detail, and 5 more. Their descriptions and schemas cost roughly 579 tokens of context every time the server is loaded.

### Is the Postmark MCP server still maintained?

Postmark 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 Postmark MCP server under?

Postmark 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/@pipeworx/mcp-postmark
- Socket report: https://socket.dev/npm/package/@pipeworx/mcp-postmark
- Repository: https://github.com/pipeworx-io/mcp-postmark
- Website: https://pipeworx.io/packs/postmark
- Changelog RSS feed: https://verifymcp.io/servers/pipeworx-io-postmark/pipeworx-mcp-postmark.xml
- Changelog JSON feed: https://verifymcp.io/servers/pipeworx-io-postmark/pipeworx-mcp-postmark.json
- HTML version of this page: https://verifymcp.io/servers/pipeworx-io-postmark/pipeworx-mcp-postmark