MCP Surface Lint
REMOTE · MCPLINT-WEB.VERCEL.APP
Statically audits MCP tool surfaces for token cost, schema quality, and design issues.
Available components
Last scanned (35 minutes ago)
Scores higher than 96% of remote servers
Reachable. Last reached 6 Nov 2026.
Category Developer Tools
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. How we score → Why this is hard to score →
Endpoint Security80
- The endpoint's TLS certificate is valid, in date, and uses a strong key. View diagnostics → Pass
- No authorisation is required to call this server. Nothing on it is marked destructive, but we can't show that an anonymous caller can only read: full credit needs the server to list at least one tool and every tool to be verifiably read-only. We use a best-effort check of tool names and descriptions to tell read-only tools from tools that change things, so some genuinely read-only tools may not get full credit. Names that start with a read verb (get, list, read, search and similar) and accurate readOnlyHint annotations help. Meet that to earn full credit, or require authorisation. See how to fix → View diagnostics → Partial
- HTTPS is enforced; there's no plaintext access path. View diagnostics → Pass
- The HSTS (Strict-Transport-Security) header is present. View diagnostics → Pass
- DNSSEC check failed: this domain isn't protected by DNSSEC. See how to fix → View diagnostics → Fail
Transport & Reachability100
- Verified streamable-http transport via a live MCP handshake. View diagnostics → Pass
Schema Quality & AI Usability85
- AI-judged instruction clarity (excellent).Pass
- Context-footprint check failed: tool/resource definitions use about 207 tokens (~207/item across 1 items; 1 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 Management100
- No destabilizing schema changes in the last 30 days.Pass
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
- Structured output schemas are declared (100% of tools); any adoption earns full credit.Pass
Tool Safety100
- No prompt-injection markers were found in the server instructions, tool names or descriptions we captured.Pass
- We read all 1 captured tool definition(s), and no name or description among them implies an irreversible operation.Pass
- An AI judge read all 1 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
Checks we ran (13)
- TLS certificate
- Authorization
- HTTPS
- HSTS header
- DNSSEC
- Transport
- Schema quality
- Stability
- Tool coverage
- Injection markers
- Destructive annotations
- Judged manipulation
- MCP protocol
Does not apply to this hosted endpoint (2)
- Supply Chain SecurityScored on package channels only. This is a hosted endpoint, so there is nothing to install or inspect.
- Provenance & TransparencyScored on package channels only. This is a hosted endpoint, so there is nothing to install or inspect.
The score does not measure everything. What the score does not measure →
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.
- 6 Nov 26 0
- We updated how we score, so this day's move reflects our rubric, not a change to the server See what changed → functional
- 28 Sept 26 0
- We updated how we score, so this day's move reflects our rubric, not a change to the server See what changed → functional
- 25 Sept 26 0
- We updated how we score, so this day's move reflects our rubric, not a change to the server See what changed → functional
- 21 Sept 26 0
- The server changed its declared name: mcplint → mcp-surface-lint security
- Server version: 0.3.3 → 0.4.0 functional
- “check_mcp_server” reworded the description of “snapshot” cosmetic
- 10 Sept 26 0
- Stability: 0.97 → pass security
- 26 Aug 26 0
- We updated how we score, so this day's move reflects our rubric, not a change to the server See what changed → functional
- 12 Aug 26 0
- Stability: unverified → 0.03 ▲ functional
- 11 Aug 26 0
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 6 Nov 2026 · Probed https://mcplint-web.vercel.app/api/mcp
TLS valid
Negotiated TLS 1.3 with TLS_AES_128_GCM_SHA256 .
| Subject | Issuer | Valid from | Valid until | Key | Signature | Serial |
|---|---|---|---|---|---|---|
| CN=*.vercel.app | CN=WR1,O=Google Trust Services,C=US | 31 Oct 2026 | 29 Jan 2027 | RSA 2048 | SHA256-RSA | 9c5f0e6a35c955e113044c86848e4cd5 |
| SANs: *.vercel.app | ||||||
| CN=WR1,O=Google Trust Services,C=US (CA) | CN=GTS Root R1,O=Google Trust Services LLC,C=US | 13 Dec 2023 | 20 Feb 2029 | RSA 2048 | SHA256-RSA | 7fd9e2c2d2048a0474b627a26d0868a7 |
| CN=GTS Root R1,O=Google Trust Services LLC,C=US (CA) | CN=GlobalSign Root CA,OU=Root CA,O=GlobalSign nv-sa,C=BE | 19 Jun 2020 | 28 Jan 2028 | RSA 4096 | SHA256-RSA | 77bd0d6cdb36f91aea210fc4f058d30d |
Background: What to check on a remote MCP endpoint →
DNSSEC insecure
Validation of mcplint-web.vercel.app. — Not signed
| Zone | DS | Keys | Algorithms | Outcome |
|---|---|---|---|---|
| . | Trust anchor | 20326, 38696 | 8, 8 | Verified |
| app. | DS published | 23684 | 8 | Verified |
| vercel.app. | No DS | Unsigned (proven) parent-signed NSEC/NSEC3 proves an unsigned delegation |
Authentication No authorisation required
The endpoint answered without asking for a token. Anyone who knows the URL can reach it.
| Result | No authorisation required |
|---|---|
| HTTP status | 200 |
| Header | Value |
|---|---|
| strict-transport-security | max-age=63072000; includeSubDomains; preload |
Background: How OAuth 2.1 works in the 2026 MCP spec →
Transports 2 probes
| Transport | URL | Outcome | Status | Location |
|---|---|---|---|---|
| streamable-http | https://mcplint-web.vercel.app/api/mcp | Verified | 200 | |
| http (plaintext) | http://mcplint-web.vercel.app/api/mcp | HTTPS enforced | 308 | https://mcplint-web.vercel.app/api/mcp |
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 →
check_mcp_server Check MCP server ~207
Statically audit an MCP tool surface from a public HTTPS URL or tools/list snapshot. Returns deterministic scores and findings without invoking any target tool or making LLM calls. When the user asks to check another installed MCP server, read that server's complete tool definitions from client context and pass them as snapshot (MCP `name` or Cursor-style `tool` both work; do not use file paths or $ref). If those definitions are unavailable, ask the user for its public endpoint or tools/list JSON instead of inventing an audit.
| Name | Type | Req | Description |
|---|---|---|---|
| headers | object | – | Optional HTTP headers sent only while reading the remote tools/list response. |
| snapshot | – | – | A tools/list JSON response, MCP Surface Lint snapshot, or client tool dump containing a tools array. Each tool needs `name`, or the Cursor-style `tool` alias. Forward another installed server's compl… |
| url | string | – | Public HTTPS Streamable HTTP MCP endpoint to inspect. |
| Name | Type | Req | Description |
|---|---|---|---|
| findingCounts | object | yes | – |
| findings | array | yes | – |
| grade | string | yes | – |
| scores | object | yes | – |
| server | object | yes | – |
| source | string | yes | – |
| staticAnalysis | boolean | yes | – |
| stats | object | yes | – |
| targetToolsInvoked | boolean | yes | – |
No examples provided.
How do I install the MCP Surface Lint server?
MCP Surface Lint is a hosted endpoint at https://mcplint-web.vercel.app/api/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.
remote · mcplint-web.vercel.app
claude mcp add --transport http dleibner-mcp-surface-lint 'https://mcplint-web.vercel.app/api/mcp'
What is the MCP Surface Lint server?
MCP Surface Lint is listed in the public MCP registry as io.github.DLeibner/mcp-surface-lint. Statically audits MCP tool surfaces for token cost, schema quality, and design issues. This page covers its hosted endpoint (https://mcplint-web.vercel.app/api/mcp).
Is the MCP Surface Lint server safe to use?
MCP Surface Lint scores 89 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 MCP Surface Lint server expose?
MCP Surface Lint exposes 1 tool: check_mcp_server. Their descriptions and schemas cost roughly 207 tokens of context every time the server is loaded.
Does the MCP Surface Lint server require authentication?
No. We connected to MCP Surface Lint without credentials and it answered, so anything it exposes is reachable by anyone who knows the address.
Is the MCP Surface Lint server still maintained?
MCP Surface Lint is still listed as active in the MCP registry. We last reached this channel on 6 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 MCP Surface Lint server?
VerifyMCP ran 13 checks on MCP Surface Lint, covering TLS certificate, Authorization, HTTPS, HSTS header and 9 more. 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.