# distance

Calculate great-circle distance between two airports and the EU261 compensation band

Agent View of the PolicyLayer registry record for `distance`. HTML page: https://policylayer.com/tools/dev-danielsuchan-eu261/distance

## Facts

- Tool: `distance`
- Server: EU261 Flight Compensation (`https://eu261.danielsuchan.dev/mcp`) — https://policylayer.com/tools/dev-danielsuchan-eu261.md
- Homepage: https://github.com/MrSucik/eu261-mcp
- Risk category: Read (Low risk)
- Registry record: grade C, identity unverified
- Server auth posture: open
- Server CORS policy: *
- Server rate-limited: no
- Parameters: 2 (2 required)
- Recommended policy verdict: Allowed

## Parameters

| Parameter | Type | Required | Description |
| --- | --- | --- | --- |
| `to` | string | yes | Destination IATA |
| `from` | string | yes | Origin IATA |

Parameters from the server's own tool schema.

## Example call (MCP tools/call, JSON-RPC 2.0)

```json
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "distance",
    "arguments": {
      "to": "<to>",
      "from": "<from>"
    }
  }
}
```

## Why distance is rated Low

This is a read-only operation that performs a mathematical calculation based on input coordinates/airport codes and returns computed results. It has no side effects, does not modify data, does not execute external operations, and does not involve financial transactions. The low severity reflects minimal risk from misuse—an agent cannot cause harm by calculating distances.

From the tool's own definition: "Tool 'distance' calculates great-circle distance between airports and compensation band information. Keywords: 'calculate' and 'distance' indicate a pure computation returning derived data with no modifications, deletions, or external state changes."

## Use case

AI agents call distance to retrieve information from EU261 Flight Compensation without modifying anything. It is typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.

## Recommended policy (PolicyLayer)

Verdict: **Allowed**. Enforced by the PolicyLayer MCP gateway (https://policylayer.com/mcp-gateway) before a call reaches EU261 Flight Compensation:

```json
{
  "version": "1",
  "default": "deny",
  "tools": {
    "distance": {}
  }
}
```

## Other tools on EU261 Flight Compensation (5)

- `check_eligibility` — Read — https://policylayer.com/tools/dev-danielsuchan-eu261/check-eligibility.md
- `compute_ev` — Read — https://policylayer.com/tools/dev-danielsuchan-eu261/compute-ev.md
- `get_price_history` — Read — https://policylayer.com/tools/dev-danielsuchan-eu261/get-price-history.md
- `list_airports` — Read — https://policylayer.com/tools/dev-danielsuchan-eu261/list-airports.md
- `record_price` — Write — https://policylayer.com/tools/dev-danielsuchan-eu261/record-price.md

## For agents

This record is a snapshot. Live verdicts and the full registry:

- Check every server in your MCP config at once: `npx -y policylayer stack`
- Vet a server before you add it: install the mcp-precheck skill — `npx skills add https://policylayer.com` (skill text: https://policylayer.com/skill.md)
- Query the registry over MCP: endpoint `https://api.policylayer.com/mcp` — tools `check_mcp_server`, `check_mcp_stack`, `check_tool`, `search_registry`, `get_change_events`

---

Source: the PolicyLayer MCP registry — one continuously verified record per MCP server. Full record: https://policylayer.com/registry?q=dev-danielsuchan-eu261 · API: https://policylayer.com/registry/api · Policy library: https://policylayer.com/policies/dev-danielsuchan-eu261