# Car Rental Brain

> True cost of car hire at 40+ airports: second driver, cover, deposits, debit cards, desk hours.

- name: com.carrentalbrain/car-rental-brain
- version: 1.0.0
- connection class: R0 (autonomous)
- trust: 83/100 flags: no-repository
- quality: 89/100 (new)
- owner: not claimed
- descriptor: https://api.protogrid.dev/v1/servers/com.carrentalbrain%2Fcar-rental-brain
- tools: https://api.protogrid.dev/v1/servers/com.carrentalbrain%2Fcar-rental-brain/tools

**An agent can connect right now, no human step.** Remote endpoint, no authentication, reachable on the last probe.

## Connection (mcpServers)

```json
{
  "mcpServers": {
    "car-rental-brain": {
      "type": "http",
      "url": "https://app.carrentalbrain.com/mcp"
    }
  }
}
```


## Trust

- hygiene: 80
- liveness: 100
- freshness: 100
- provenance: 55
- drivers: +dns-namespace +website +reachable +uptime-100% +updated-1d-ago -no-repository
- Derived from observable signals (official registry feed and our own credential-free probes); no code audit performed.

## Quality 89/100 (new)

### protocol: 75 (weight 25)

- warn `protocol.modern`: newest supported version is 2025-06-18; 2026-07-28 not supported, older versions are deprecated until 2027-07-28
- n/a `protocol.stateless`: only applies to 2026-07-28 servers
- pass `protocol.transport`: streamable HTTP
- n/a `protocol.list_ttl`: only applies to 2026-07-28 servers

### authorization: n/a (weight 15)

- n/a `auth.prm`, `auth.as_metadata`, `auth.cimd`: no remote uses OAuth
- n/a `auth.secret_in_url`: no templated URL

### tool hygiene: 100 (weight 30)

- pass `tools.descriptions`: every tool has a description
- pass `tools.description_length`: descriptions are concise
- pass `tools.schemas`: every tool has an object input schema
- pass `tools.annotations`: 6 of 6 tools declare readOnlyHint or destructiveHint
- pass `tools.directory_hints`: every tool declares readOnlyHint, destructiveHint, idempotentHint and openWorldHint
- pass `tools.token_cost`: about 968 tokens to load every tool
- pass `tools.api_dump`: tools are not a one-to-one API dump

### stability: n/a (weight 15)

- n/a `stability.changes`, `stability.rug_pull`: tool history recorded for 1 of the 7 days needed

### dependencies: n/a (weight 15)

- n/a `deps.known_vulns`, `deps.mcp_sdk_version`, `deps.resolvable`: no npm or PyPI package

- tools: 6, about 968 tokens to load them all
- tool set hash: 1dba4779e5637ef1c3139614bea0f13a
- tools last changed: 2026-10-19T23:33:42.137Z
- badge: [![protogrid quality](https://protogrid.dev/badge/com.carrentalbrain/car-rental-brain.svg)](https://protogrid.dev/servers/com.carrentalbrain/car-rental-brain)
- Checks run on what our credential-free, read-only probes observe; tools are never called and no code audit is performed.

### Tool changes

- 2026-10-19 `build_search_link` changed (title, description, outputSchema)
  - before: A link for the PERSON to open: live prices for their exact dates and needs, ranked by the total they will actually pay, where they can book. Always give this to the person.
  - after: A link for the PERSON to open: live prices for their exact dates and needs, ranked by the total they will actually pay, where they can book.
- 2026-10-19 `supplier_terms` changed (title)
- 2026-10-19 `compare_airports` changed (title)
- 2026-10-19 `airport_costs` changed (title)
- 2026-10-19 `list_airports` changed (title)
- 2026-10-19 `get_capabilities` changed (title)

Full history: https://api.protogrid.dev/v1/servers/com.carrentalbrain%2Fcar-rental-brain/changes

## Remotes

- https://app.carrentalbrain.com/mcp (streamable-http, auth none, reachable true, uptime30d 1)

## Packages

_none_

## Tools (6)

- `airport_costs`: The true cost of hiring a car at one airport: per-day price for the car alone, with a second driver, with full cover, automatic, no-deposit (from + typical); by pick-up month; second-driver fees; deposits; debit-card acceptance; desk closing times and out-of-hours fees; policies.
- `build_search_link`: A link for the PERSON to open: live prices for their exact dates and needs, ranked by the total they will actually pay, where they can book.
- `compare_airports`: Rank airports by real cost (car only / with driver / with cover), typical deposit, debit-card friendliness or late desk hours. 'Where in Spain is car hire cheapest in March?'
- `get_capabilities`: What Car Rental Brain measures, how fresh it is, and which airports/countries are covered.
- `list_airports`: Airports we measure, with the typical rental price per day. Filter by country.
- `supplier_terms`: Per supplier at an airport: typical price per day, second-driver fee, full-cover price, deposit held, whether the desk takes a debit card, and customers' desk review scores.