Mozilla Observatory
NPM · @PIPEWORX/MCP-MOZILLA-OBSERVATORY · 2 COMPONENTS
MDN HTTP Observatory — grade any website's HTTP security headers and get the specific fixes, from…
Available components
Last scanned (8 hours ago)
Scores higher than 76% of npm servers
Category Security
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. How we score → Why this is hard to score →
Supply Chain Security100
- No malware found by supply-chain analysis.Pass
- No known CVEs affecting this package version or its production dependencies.Pass
- No install/post-install scripts declared.Pass
- No production dependencies, so there is no dependency health to assess. View diagnostics → Pass
Provenance & Transparency97
- Source repository is publicly reachable at the declared URL. View diagnostics → Pass
- Cryptographically verified build provenance (signed, bound to pipeworx-io/mcp-mozilla-observatory). View diagnostics → Pass
- Clear OSI-approved license (MIT).Pass
- Actively maintained (last published 1 days ago).Pass
- Disclosure check failed: no security disclosure policy was found in the source repository. See how to fix → Fail
Schema Quality & AI Usability70
- AI-judged instruction clarity (excellent).Pass
- 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. See how to fix → Fail
- Usage-examples check failed: none of the tools include examples. See how to fix → Fail
Stability & Change Management23
- Stability observed for 7 of 30 days with no destabilising changes; credit accrues until the full window elapses.Partial
Tool Coverage100
- 100% of tools have a non-trivial description (not blank, and not just the tool's name).Pass
- 100% of tool parameters carry a description.Pass
Tool Safety100
- No prompt-injection markers were found in the server instructions, tool names or descriptions we captured.Pass
- We read all 3 captured tool definition(s), and no name or description among them implies an irreversible operation.Pass
- An AI judge read all 4 captured unit(s) of tool text and found none that tries to manipulate the model reading it.Pass
Capabilities100
- Implements a supported MCP spec version (2025-11-25); the latest is 2026-07-28.Pass
Every change we have recorded for this component, newest first. Security-relevant changes are always shown. ▲ marks a change for the better, ▼ a change for the worse; unmarked changes are neutral.
- 4 Nov 26 +16
- Malware scan: unverified → pass ▲ security
- 3 Nov 26 −13
- Malware scan: pass → unverified ▼ security
- Security disclosure: fail → unverified ▼ functional
- Stability: unverified → 0.17 ▲ functional
- Package version: 0.2.0 → 0.2.1 functional
- 1 Nov 26 0
- Security disclosure: unverified → fail ▼ functional
- 31 Oct 26 0
- Security disclosure: fail → unverified ▼ functional
- 29 Oct 26 80
First indexed and scored.
Diagnostic detail from the automated scan of this channel: what the scanner observed at each step, so you can see exactly where a check passed or failed. It is informational only and never changes the trust score.
Captured 5 Nov 2026 · Analysed npm/@pipeworx/mcp-mozilla-observatory@0.2.1
Provenance Verified
A signed build attestation was found and verified, binding this exact artifact to the source repository it claims to come from.
| Result | Verified |
|---|---|
| Ecosystem | npm |
| Reason | Verified |
| Discovered via | Registry attestation endpoint |
| Source repo | pipeworx-io/mcp-mozilla-observatory |
| Certificate issuer | https://token.actions.githubusercontent.com |
| Certificate SAN | https://github.com/pipeworx-io/mcp-mozilla-observatory/.github/workflows/publish.yml@refs/heads/main |
| Rekor log index | 3655559924 |
| Predicate type | SLSA build provenance https://slsa.dev/provenance/v1 |
| Subject digest | sha512:e8d689d598fd44dbda3c8d60a1f0021358270ee929ce72245149e75ae74731cd009bad9c057ccd4dae8ed7b9eeddfd866c7ecacdf3e399f8f8fee9ae1 |
Background: How many MCP packages publish verified provenance →
Dependencies 0 packages
| Packages resolved | 0 |
|---|---|
| Tree resolution | Complete |
Background: SBOMs and build attestations, explained →
The tools this component advertises to a client, with an estimated token cost for each. Expand a tool to see its parameters and schema. The per-tool counts are indicative and are not scored directly; the schema's total context footprint is one signal in Schema Quality & AI Usability. A tool's description is untrusted text the model reads on every call, which is what makes this list a security surface and not just an inventory: how tool poisoning works →
observatory_grade_distribution ~68
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.
Input schema present but exposes no named parameters.
No output schema declared.
No examples provided.
observatory_results ~252
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.
| Name | Type | Req | Description |
|---|---|---|---|
| history_limit | number | – | How many historical scans to return, most recent first. Default 10, max 100. |
| host | string | yes | 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. |
No output schema declared.
No examples provided.
observatory_scan ~151
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.
| Name | Type | Req | Description |
|---|---|---|---|
| host | string | yes | Hostname to scan, e.g. "mozilla.org", "www.whitehouse.gov". A full URL is accepted and reduced to its host. |
No output schema declared.
No examples provided.
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.
npm · @pipeworx/mcp-mozilla-observatory
claude mcp add pipeworx-io-mozilla-observatory -- npx -y @pipeworx/mcp-mozilla-observatory
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.