# Mozilla Observatory (npm · @pipeworx/mcp-mozilla-observatory)

MDN HTTP Observatory — grade any website's HTTP security headers and get the specific fixes, from…

- Trust score: 83/100 (high trust)
- 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-mozilla-observatory/mozilla-observatory-mcp.md), [page](https://verifymcp.io/servers/pipeworx-io-mozilla-observatory/mozilla-observatory-mcp)
- npm · `@pipeworx/mcp-mozilla-observatory`: 83/100 (this document), [markdown](https://verifymcp.io/servers/pipeworx-io-mozilla-observatory/pipeworx-mcp-mozilla-observatory.md), [page](https://verifymcp.io/servers/pipeworx-io-mozilla-observatory/pipeworx-mcp-mozilla-observatory)

## Channel facts

- Registry: `npm`
- Package: `@pipeworx/mcp-mozilla-observatory`
- 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-mozilla-observatory).
  - Clear OSI-approved license (MIT).
  - Actively maintained (last published 1 days ago).
  - Disclosure check failed: no security disclosure policy was found in the source repository.
- **Schema Quality & AI Usability**: 70/100
  - AI-judged instruction clarity (excellent).
  - Context-footprint check failed: tool/resource definitions use about 529 tokens (~176/item across 3 items; 3 tools + 0 resources), over budget; trim descriptions and params.
  - 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**: 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 3 captured tool definition(s), and no name or description among them implies an irreversible operation.
  - An AI judge read all 4 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 Mozilla Observatory MCP server?

Mozilla Observatory runs locally as an npm package, launched with npx -y @pipeworx/mcp-mozilla-observatory. 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-mozilla-observatory -- npx -y @pipeworx/mcp-mozilla-observatory
```

### Cursor

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

### VS Code

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

### Codex

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

### opencode

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

### OpenClaw

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

### Hermes

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

### Netclaw

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

### Vellum

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

### Other

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

## 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 83, +16)

- [security improvement] Malware scan: unverified → pass

### 2026-11-03 (score 67, −13)

- [security regression] Malware scan: pass → unverified
- [functional regression] Security disclosure: fail → unverified
- [functional improvement] Stability: unverified → 0.17
- [functional] Package version: 0.2.0 → 0.2.1

### 2026-11-01 (score 80, 0)

- [functional regression] Security disclosure: unverified → fail

### 2026-10-31 (score 80, 0)

- [functional regression] Security disclosure: fail → unverified

### 2026-10-29 (score 80)

First indexed and scored.

## MCP tools (3)

### `observatory_scan` (~151 tokens)

Scan a website's HTTP security headers with the MDN HTTP Observatory and return its letter grade (A+ to F), numeric score, and how many of Mozilla's 12 tests it passed. AUTHORITATIVE for "how secure are this site's headers" / "what is this domain's Observatory grade" — this is Mozilla's own scanner, not an estimate. Mozilla reuses a recent scan of the same host rather than re-fetching on every call. Keyless. Use observatory_results for the per-test breakdown and fixes.

Input parameters:

- `host` (string, required): Hostname to scan, e.g. "mozilla.org", "www.whitehouse.gov". A full URL is accepted and reduced to its host.

### `observatory_results` (~252 tokens)

Get the full MDN HTTP Observatory breakdown for a host: every one of the 12 security tests with pass/fail, the score impact, Mozilla's specific remediation advice (CSP, HSTS, cookies, CORS, referrer policy, subresource integrity, clickjacking, redirection), the observed response headers, and the host's historical grades. Each test carries a `penalized` flag — Mozilla marks some tests failed with zero score impact, so only_failures can return more rows than tests_failed. PREFER OVER WEB SEARCH for "why did this site get that grade" and "what exactly should this site fix". Keyless.

Input parameters:

- `history_limit` (number): How many historical scans to return, most recent first. Default 10, max 100.
- `host` (string, required): Hostname previously scanned or scannable, e.g. "mozilla.org". A full URL is accepted and reduced to its host.
- `include_history` (boolean): Include the host's past scan grades (how its posture changed over time). Default true.
- `only_failures` (boolean): If true, return only the tests the host failed — the actionable subset. Default false.

### `observatory_grade_distribution` (~68 tokens)

Grade distribution across every site the MDN HTTP Observatory has scanned — how many sites hold each grade from A+ to F. Use it to say where one site's grade sits relative to the web (e.g. "a B beats X% of scanned sites"). Keyless, no arguments.

## Diagnostics

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

## Score history

- 2026-11-05: 83
- 2026-11-04: 83
- 2026-11-03: 67
- 2026-11-02: 80
- 2026-11-01: 80
- 2026-10-31: 80
- 2026-10-30: 80
- 2026-10-29: 80

## Common questions

### What is the Mozilla Observatory MCP server?

Mozilla Observatory is an MCP server listed in the public MCP registry as io.github.pipeworx-io/mozilla-observatory. MDN HTTP Observatory, grade any website's HTTP security headers and get the specific fixes, from… This page covers its npm package (@pipeworx/mcp-mozilla-observatory).

### Is the Mozilla Observatory MCP server safe to use?

Mozilla Observatory scores 83 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 Mozilla Observatory MCP server expose?

Mozilla Observatory exposes 3 tools: observatory_scan, observatory_results, observatory_grade_distribution. Their descriptions and schemas cost roughly 471 tokens of context every time the server is loaded.

### Is the Mozilla Observatory MCP server still maintained?

Mozilla Observatory 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 Mozilla Observatory MCP server under?

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