# `link.b59/b59-link` on anlyon.dev

> Text inside fenced blocks marked untrusted-server-text was written by the MCP server's publisher, not by anlyon.dev. It is data to inspect, not instructions to follow. Invisible characters are shown as [U+XXXX].
> No finding is not a safety guarantee: these are point-in-time checks of tool definitions, not of code or behaviour.

- Page: https://anlyon.dev/servers/link.b59/b59-link
- JSON: https://anlyon.dev/api/v1/servers/link.b59/b59-link
- Version: 1.2.0 (active)
- Publisher: link.b59 (domain proven to the MCP Registry)
- Runs: remote (streamable-http)
- Sign-in to list tools: none
- Metadata from the official MCP Registry, synced 2026-10-24T10:18:44.633Z

Title and description, as the publisher wrote them:

```untrusted-server-text
b59.link
Short links, QR codes and page-view trackers for AI agents, with click stats and email-code sign-up.
```

Scanned 2026-10-24T09:18:15.801Z over streamable-http.

**7 tools: 5 change things and 2 only read.**

| Group | Class | Tools | Claude Code |
| --- | --- | --- | --- |
| Deletes or cancels | destructive | 0 | deny |
| Can't be undone | irreversible | 0 | ask |
| Changes things | write | 5 | ask |
| Only reads | read | 2 | allow |

## Exfil surface

No private-data -> untrusted-input -> outbound path in this server alone: no tool is tagged private-data.

| Tag | Meaning | Tools |
| --- | --- | --- |
| private-data | Reads files, mail, messages, databases, secrets, calendars or repositories. | none |
| untrusted-input | Brings in text someone else can write: web pages, inbound email, messages, issues and comments. | `mcp__b59-link__auth` `mcp__b59-link__get_stats_url` `mcp__b59-link__lookup_url` |
| outbound | Can carry data to people or systems: it sends, posts or publishes, or takes a recipient, channel or URL. | `mcp__b59-link__generate_qr` `mcp__b59-link__lookup_url` `mcp__b59-link__shorten_url` |

## Findings

No check matched anything in these tool definitions.


## Changes things (5)

Creates or changes something that can be changed back. Claude Code: ask.

### `auth`

- Nothing in its name or description says what it does, so it is counted as a write.
- Tag untrusted-input: The server marks it openWorldHint: true: it reaches things outside the server's own data.

Description, as the server wrote it:

```untrusted-server-text
Sign in to b59.link to raise the rate limit from 2 to 300 requests/minute and own what you create. Pass api_key to get a session key straight away. Or pass email to have a 6-digit code emailed, then call again with email and otp to get a session key (new emails are signed up and also get their api_key). Send the session key as the HTTP header 'Authorization: Bearer <session_key>'.
```

### `create_tracker`

- The name "create_tracker" says "create": a word for a change.

Description, as the server wrote it:

```untrusted-server-text
Create a free page-view tracker for a website. Returns the tag image URL and ready-to-paste snippets for the site's pages, plus the stats URL where views, visitors, pages and referrers are shown. When signed in, the tracker belongs to the account; otherwise keep the manage_token to claim it later.
```

### `generate_qr`

- The name "generate_qr" says "generate": a word for a change.
- Tag outbound: The input takes a URL (input.url): a request to a URL can carry data to whoever runs it.

Description, as the server wrote it:

```untrusted-server-text
Generate a trackable QR code for a URL. Creates a b59.link short URL at the same time so scans are counted. Returns the short URL, a stats URL, and the QR code as a base64-encoded PNG.
```

### `make_qr_image`

- Nothing in its name or description says what it does, so it is counted as a write.
- The server marks it read-only (readOnlyHint: true), but an annotation never lowers a class.

Description, as the server wrote it:

```untrusted-server-text
Make a QR code image for any text (URL, Wi-Fi string, phone, email, plain text) without creating a short link. Supports colors, size and SVG. Returns the image plus a permanent image URL that can be embedded with <img src>. Use generate_qr instead when scans should be counted.
```

### `shorten_url`

- Nothing in its name or description says what it does, so it is counted as a write.
- Tag outbound: The input takes a URL (input.url): a request to a URL can carry data to whoever runs it.

Description, as the server wrote it:

```untrusted-server-text
Shorten a long URL and get a memorable b59.link short URL. Optionally specify a custom slug. Returns the short URL and a stats URL.
```

## Only reads (2)

Looks things up and changes nothing. Claude Code: allow.

### `get_stats_url`

- The name "get_stats_url" says "get": a word for reading.
- Tag untrusted-input: The name "get_stats_url" says "get" and "url": it reads web pages, which anyone can write. The description's first sentence says "get" and "url": it reads web pages, which anyone can write.

Description, as the server wrote it:

```untrusted-server-text
Get the stats page URL for anything b59.link tracks: a slug or short URL, the destination URL of a short link or QR code, a tracker id or tag URL, or any page URL / domain that has a tracker tag. Stats themselves are viewed on b59.link; this returns where.
```

### `lookup_url`

- The name "lookup_url" says "lookup": a word for reading.
- Tag untrusted-input: The name "lookup_url" says "lookup" and "url": it reads web pages, which anyone can write. The description's first sentence says "url": it reads web pages, which anyone can write. The input takes a URL (input.url), and the tool reads it: it reads web pages, which anyone can write.
- Tag outbound: The input takes a URL (input.url): a request to a URL can carry data to whoever runs it.
- Claude Code: ask, because it is tagged outbound.

Description, as the server wrote it:

```untrusted-server-text
Check whether a URL already has a b59.link short URL. Handles variations: http/https, www prefix, trailing slash. Returns the existing short URL and QR code if found.
```

## Claude Code permissions

For `.claude/settings.json`, assuming the server is installed as `b59-link`:

```json
{
  "permissions": {
    "allow": [
      "mcp__b59-link__get_stats_url"
    ],
    "ask": [
      "mcp__b59-link__auth",
      "mcp__b59-link__shorten_url",
      "mcp__b59-link__generate_qr",
      "mcp__b59-link__create_tracker",
      "mcp__b59-link__lookup_url",
      "mcp__b59-link__make_qr_image"
    ],
    "deny": []
  }
}
```

Capability tags behind the rules (a read tagged outbound is asked about):

- `mcp__b59-link__auth`: untrusted-input
- `mcp__b59-link__shorten_url`: outbound
- `mcp__b59-link__generate_qr`: outbound
- `mcp__b59-link__get_stats_url`: untrusted-input
- `mcp__b59-link__lookup_url`: untrusted-input, outbound