# mcp-pin (npm · mcp-pin)

Check if an MCP server's tool definitions changed after approval, from a signed public log.

- Trust score: 85/100 (high trust)
- Change this week: +4
- Registry status: active
- Liveness: live
- Owner verified: no
- Last scored: 2026-10-22

## Components

- npm · `mcp-pin`: 85/100 (this document), [markdown](https://verifymcp.io/servers/gautamtalksdev-mcp-pin/mcp-pin.md), [page](https://verifymcp.io/servers/gautamtalksdev-mcp-pin/mcp-pin)

## Channel facts

- Registry: `npm`
- Package: `mcp-pin`
- Version: `0.2.3`
- 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 2026-10-22.

- **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**: 100/100
  - Source repository is publicly reachable at the declared URL.
  - Cryptographically verified build provenance (signed, bound to GautamTalksDev/mcp-pin).
  - Clear OSI-approved license (MIT).
  - Actively maintained (last published 15 days ago).
  - Publishes a security disclosure policy (SECURITY.md).
- **Schema Quality & AI Usability**: 74/100
  - AI-judged instruction clarity (excellent).
  - Context-footprint check failed: tool/resource definitions use about 694 tokens (~173/item across 4 items; 4 tools + 0 resources), over budget; trim descriptions and params.
  - Usage-examples check failed: none of the tools include examples.
- **Stability & Change Management**: 27/100
  - Stability observed for 8 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 4 captured tool definition(s), and no name or description among them implies an irreversible operation.
  - An AI judge read all 5 captured unit(s) of tool text and found none that tries to manipulate the model reading it.
- **Capabilities**: 100/100
  - Implements a current MCP spec version (2026-07-28).

## Install

### How do I install the mcp-pin server?

mcp-pin runs locally as an npm package, launched with npx -y mcp-pin. 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 gautamtalksdev-mcp-pin -- npx -y mcp-pin
```

### Cursor

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

### VS Code

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

### Codex

```bash
codex mcp add gautamtalksdev-mcp-pin -- npx -y mcp-pin
```

### opencode

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

### OpenClaw

```bash
openclaw mcp add gautamtalksdev-mcp-pin --command npx --arg -y --arg mcp-pin
```

### Hermes

```yaml
mcp_servers:
  gautamtalksdev-mcp-pin:
    command: "npx"
    args: ["-y", "mcp-pin"]
```

### Netclaw

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

### Vellum

```bash
assistant mcp add gautamtalksdev-mcp-pin -t stdio -c npx -a -y mcp-pin
```

### Other

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

## 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.

### 2026-10-22 (score 85, +4)

- [functional improvement] Stability: unverified → 0.27

### 2026-10-17 (score 81, 0)

- [functional improvement] Security disclosure: unverified → pass

### 2026-10-16 (score 81, 0)

- [functional regression] Security disclosure: pass → unverified

### 2026-10-14 (score 81, +31)

- [security improvement] Injection markers: unverified → pass
- [security] First check of Judged manipulation: pass
- [security] Stability: Stability not yet verified: not enough scan history yet (needs a 30-day window).
- [functional improvement] Tool coverage: unverified → 100
- [functional improvement] MCP protocol: unverified → pass
- [functional] First check of Schema quality: fail
- [functional] First check of Schema quality: excellent
- [functional] First check of Destructive annotations: pass
- [functional] First check of Schema quality: fail
- [functional] First check of Tool coverage: 100

### 2026-10-11 (score 50, +15)

- [security improvement] Malware scan: unverified → pass

### 2026-10-07 (score 35)

First indexed and scored.

## MCP tools (4)

### `mcp_pin_server_status` (~183 tokens)

Public MCP server status

Look up a public MCP server in the signed public log kept by mcp-pin, to see whether its tool definitions have changed and when. Use it before installing or approving an MCP server, or when the user asks if a server changed. Input: query, an npm package name (for example @modelcontextprotocol/server-filesystem) or part of one. Returns up to 5 matching servers, exact name first: name, registry, tool count, first seen date, last change date with the earliest day it could have happened, last successful check, and a link to the full history. Only names, dates and counts are returned, never tool descriptions. An unchanged server is not proof of safety: a server can be hostile from its first version.

Input parameters:

- `query` (string, required): npm package name or part of it, for example "server-filesystem".

### `mcp_pin_my_servers` (~132 tokens)

Servers mcp-pin protects here

List the MCP servers mcp-pin protects on this machine and whether any of them has a change waiting for review. Use it when the user asks which servers are pinned, or after mcp-pin blocked a server. No input. Returns, per server: id, label, tool and prompt counts, the date it was approved, and pending (true when a change is waiting). It never returns definitions or changed text. For a pending change, call mcp_pin_change_summary with its id, then ask the user to run "mcp-pin review <id>" in a terminal to read the diff.

### `mcp_pin_change_summary` (~172 tokens)

What kind of change is waiting

Explain what kind of change mcp-pin blocked on one pinned server, without the changed text. Use it after mcp_pin_my_servers shows pending: true, to tell the user what they are about to review. Input: id, the 16-character server id from mcp_pin_my_servers. Returns one entry per changed tool, prompt or instruction block with label keys: new-tool, new-prompt, new-field, new-argument, instruction, secrets, link, hidden, hints, field-type, output-schema, field-removed, removed, wording. Approving is always the user's decision: never run "mcp-pin approve" for them.

Input parameters:

- `id` (string, required): Server id from mcp_pin_my_servers, for example "18d57558e558a5f4".

### `mcp_pin_how_to_protect` (~132 tokens)

How to protect MCP servers

Give the exact steps to put mcp-pin in front of MCP servers in one AI app, so the user can copy them. Use it when the user asks how to protect their MCP servers or set up mcp-pin. Input: app, one of every_app, claude_code, claude_desktop, cursor, vscode, codex, gemini_cli, one_server. Returns the commands or config text for that app and the version they pin. It changes nothing by itself.

Input parameters:

- `app` (string, required): Which app to protect. every_app covers all of them at once.

## Diagnostics

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

## Score history

- 2026-10-22: 85
- 2026-10-21: 81
- 2026-10-20: 81
- 2026-10-19: 81
- 2026-10-18: 81
- 2026-10-17: 81
- 2026-10-16: 81
- 2026-10-15: 81
- 2026-10-14: 81
- 2026-10-13: 50
- 2026-10-12: 50
- 2026-10-11: 50
- 2026-10-07: 35

## Common questions

### What is the mcp-pin server?

mcp-pin is listed in the public MCP registry as io.github.GautamTalksDev/mcp-pin. Check if an MCP server's tool definitions changed after approval, from a signed public log. This page covers its npm package (mcp-pin).

### Is the mcp-pin server safe to use?

mcp-pin scores 85 out of 100 on VerifyMCP. We found no known CVEs affecting it as of 22 October 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 mcp-pin server expose?

mcp-pin exposes 4 tools: mcp_pin_server_status, mcp_pin_my_servers, mcp_pin_change_summary, mcp_pin_how_to_protect. Their descriptions and schemas cost roughly 619 tokens of context every time the server is loaded.

### Is the mcp-pin server still maintained?

mcp-pin is still listed as active in the MCP registry. We last reached this channel on 22 October 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 mcp-pin server under?

mcp-pin 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/mcp-pin
- Socket report: https://socket.dev/npm/package/mcp-pin
- Repository: https://github.com/GautamTalksDev/mcp-pin
- Website: https://mcp-pin.gautamkhosla.com/
- Changelog RSS feed: https://verifymcp.io/servers/gautamtalksdev-mcp-pin/mcp-pin.xml
- Changelog JSON feed: https://verifymcp.io/servers/gautamtalksdev-mcp-pin/mcp-pin.json
- HTML version of this page: https://verifymcp.io/servers/gautamtalksdev-mcp-pin/mcp-pin