# `io.github.theluckystrike/mortgage-rates-today-mcp` 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/io.github.theluckystrike/mortgage-rates-today-mcp
- JSON: https://anlyon.dev/api/v1/servers/io.github.theluckystrike/mortgage-rates-today-mcp
- Version: 1.0.0 (active)
- Publisher: io.github.theluckystrike (GitHub account)
- Runs: remote (streamable-http)
- Sign-in to list tools: none
- Repository: https://github.com/theluckystrike/mortgage-rates-today-mcp
- Metadata from the official MCP Registry, synced 2026-11-05T14:18:25.049Z

Title and description, as the publisher wrote them:

```untrusted-server-text
Mortgage Rates Today MCP
Mortgage rates today: Freddie Mac weekly 30 and 15 year fixed averages, history and payment math.
```

Scanned 2026-11-05T14:18:28.845Z over streamable-http.

**4 tools: 1 do something that can't be undone and 3 only read.**

| Group | Class | Tools | Claude Code |
| --- | --- | --- | --- |
| Deletes or cancels | destructive | 0 | deny |
| Can't be undone | irreversible | 1 | ask |
| Changes things | write | 0 | ask |
| Only reads | read | 3 | allow |

## Exfil surface

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

| 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__mortgage-rates-today__calculate_mortgage_payment` `mcp__mortgage-rates-today__get_mortgage_rate_history` `mcp__mortgage-rates-today__get_mortgage_rate_on_date` `mcp__mortgage-rates-today__get_mortgage_rates_today` |
| outbound | Can carry data to people or systems: it sends, posts or publishes, or takes a recipient, channel or URL. | none |

## Findings

- **warn** Annotations that disagree with the tool in `calculate_mortgage_payment` ([annotation-conflict](https://anlyon.dev/methodology#annotation-conflict))

```untrusted-server-text
The server marks "calculate_mortgage_payment" read-only (readOnlyHint: true), and its own name, description or input give the class "irreversible".

annotations: {"readOnlyHint":true,"destructiveHint":false,"idempotentHint":true,"openWorldHint":true}; The name "calculate_mortgage_payment" says "payment": a word that usually means money moves, which cannot be taken back.
```


## Can't be undone (1)

Sends, pays, publishes or merges: once done, it cannot be taken back. Claude Code: ask.

### `calculate_mortgage_payment`

- The name "calculate_mortgage_payment" says "payment": a word that usually means money moves, which cannot be taken back.
- The server marks it read-only (readOnlyHint: true), but an annotation never lowers a class.
- Tag untrusted-input: The server marks it openWorldHint: true: it reaches things outside the server's own data.
- Findings: warn annotation-conflict

Description, as the server wrote it:

```untrusted-server-text
Monthly principal and interest and total interest for a fixed-rate loan. Without a rate it uses this week's Freddie Mac average for 30-year or 15-year terms, and compares it with the average a year earlier. Taxes, insurance and PMI are not included.
```

## Only reads (3)

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

### `get_mortgage_rate_history`

- The name "get_mortgage_rate_history" says "get": a word for reading.
- 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
Freddie Mac PMMS 30-year or 15-year fixed averages between two dates as weekly rows or monthly or annual averages, with the high, low and change over the range. Default is the last 52 weeks of the 30-year rate.
```

### `get_mortgage_rate_on_date`

- The name "get_mortgage_rate_on_date" says "get": a word for reading.
- 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
The Freddie Mac PMMS weekly average 30-year and 15-year fixed rates (plus 5/1 ARM and points where published) in force on a date, from 1971-04-02 to today.
```

### `get_mortgage_rates_today`

- The name "get_mortgage_rates_today" says "get": a word for reading.
- 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
Latest Freddie Mac PMMS weekly average 30-year and 15-year fixed mortgage rates, read at call time from freddiemac.com: rate, week-over-week change, rate a year ago, 52-week high, low and average, the week date and the next expected release. National averages for well-qualified conventional purchase borrowers.
```

## Claude Code permissions

For `.claude/settings.json`, assuming the server is installed as `mortgage-rates-today`:

```json
{
  "permissions": {
    "allow": [
      "mcp__mortgage-rates-today__get_mortgage_rates_today",
      "mcp__mortgage-rates-today__get_mortgage_rate_on_date",
      "mcp__mortgage-rates-today__get_mortgage_rate_history"
    ],
    "ask": [
      "mcp__mortgage-rates-today__calculate_mortgage_payment"
    ],
    "deny": []
  }
}
```

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

- `mcp__mortgage-rates-today__get_mortgage_rates_today`: untrusted-input
- `mcp__mortgage-rates-today__get_mortgage_rate_on_date`: untrusted-input
- `mcp__mortgage-rates-today__get_mortgage_rate_history`: untrusted-input
- `mcp__mortgage-rates-today__calculate_mortgage_payment`: untrusted-input