# Car Rental Brain (remote · app.carrentalbrain.com)

Real cost of car hire at 120+ airports: second driver, cover, deposits, debit cards, desk hours.

- Trust score: 66/100 (medium)
- Registry status: active
- Liveness: live
- Owner verified: no
- Last scored: 2026-10-23

## Components

- remote · `app.carrentalbrain.com`: 66/100 (this document), [markdown](https://verifymcp.io/servers/com-carrentalbrain-car-rental-brain/app.md), [page](https://verifymcp.io/servers/com-carrentalbrain-car-rental-brain/app)

## Channel facts

- Endpoint: `https://app.carrentalbrain.com/mcp`
- Transports: `streamable-http`
- Auth: `none`
- Version: `1.0.1`

## Trust breakdown

How this component scores in each security and reliability category. Every signal is checked automatically against the live server, 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 2026-10-23.

- **Endpoint Security**: 63/100
  - The endpoint's TLS certificate is valid, in date, and uses a strong key.
  - No authorisation is required to call this server. Every tool declares its destructiveHint and none is destructive, so open access doesn't expose one.
  - HTTPS check failed: the endpoint is reachable over plaintext HTTP.
  - HSTS check failed: the Strict-Transport-Security header is absent.
  - DNSSEC check failed: this domain isn't protected by DNSSEC.
- **Transport & Reachability**: 100/100
  - Verified streamable-http transport via a live MCP handshake.
- **Schema Quality & AI Usability**: 70/100
  - AI-judged instruction clarity (good).
  - Context-footprint check failed: tool/resource definitions use about 930 tokens (~155/item across 6 items; 6 tools + 0 resources), over budget; trim descriptions and params.
  - Usage-examples check failed: none of the tools include examples.
- **Stability & Change Management**: 13/100
  - Stability observed for 4 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.
  - Structured output schemas are declared (100% of tools); any adoption earns full credit.
- **Tool Safety**: 100/100
  - No prompt-injection markers were found in the server instructions, tool names or descriptions we captured.
  - We read all 6 captured tool definition(s), and no name or description among them implies an irreversible operation.
  - An AI judge read all 7 captured unit(s) of tool text and found none that tries to manipulate the model reading it.
- **Capabilities**: 60/100
  - Spec-recency check failed: implements MCP spec 2025-06-18; the latest is 2026-07-28.

## Install

### How do I install the Car Rental Brain MCP server?

Car Rental Brain is a hosted endpoint at https://app.carrentalbrain.com/mcp, so there is nothing to install locally. 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 --transport http com-carrentalbrain-car-rental-brain 'https://app.carrentalbrain.com/mcp'
```

### Cursor

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

### VS Code

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

### Codex

```toml
[mcp_servers.com-carrentalbrain-car-rental-brain]
url = "https://app.carrentalbrain.com/mcp"
```

### opencode

```json
{
  "$schema": "https://opencode.ai/config.json",
  "mcp": {
    "com-carrentalbrain-car-rental-brain": {
      "type": "remote",
      "url": "https://app.carrentalbrain.com/mcp",
      "enabled": true
    }
  }
}
```

### OpenClaw

```bash
openclaw mcp add com-carrentalbrain-car-rental-brain --url 'https://app.carrentalbrain.com/mcp' --transport streamable-http
```

### Hermes

```yaml
mcp_servers:
  com-carrentalbrain-car-rental-brain:
    url: "https://app.carrentalbrain.com/mcp"
```

### Netclaw

```json
{
  "McpServers": {
    "com-carrentalbrain-car-rental-brain": {
      "Transport": "http",
      "Url": "https://app.carrentalbrain.com/mcp"
    }
  }
}
```

### Vellum

```bash
assistant mcp add com-carrentalbrain-car-rental-brain -t streamable-http -u 'https://app.carrentalbrain.com/mcp'
```

### Other

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

The mcpServers block is a cross-client convention. Remote transports vary, so check your client's docs.

## 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 66, +2)

- [security] Tool “airport_costs” rewrote its description, which is the text the model reads
- [security] Tool “build_search_link” rewrote its description, which is the text the model reads
- [security] Tool “compare_airports” rewrote its description, which is the text the model reads
- [security] Tool “get_capabilities” rewrote its description, which is the text the model reads
- [security] Tool “list_airports” rewrote its description, which is the text the model reads
- [security] Tool “supplier_terms” rewrote its description, which is the text the model reads
- [functional regression] Schema quality: 120 → 155
- [functional improvement] Tool coverage: 71% → 100%
- [functional] Server version: 1.0.0 → 1.0.1
- [cosmetic] “build_search_link” reworded the description of “age”
- [cosmetic] “build_search_link” reworded the description of “automatic”
- [cosmetic] “build_search_link” reworded the description of “car_type”
- [cosmetic] “build_search_link” reworded the description of “debit_card”
- [cosmetic] “build_search_link” reworded the description of “extra_driver”
- [cosmetic] “compare_airports” reworded the description of “limit”
- [cosmetic] “compare_airports” reworded the description of “sort_by”

### 2026-10-21 (score 64, +1)

No change was recorded against any check on this day. Stability & Change Management went from 3 to 7. That category is still filling its 30-day observation window: 1 days of observed history at the previous scan, 2 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-10-20 (score 63, 0)

- [functional improvement] Stability: unverified → 0.03

### 2026-10-19 (score 63)

First indexed and scored.

## MCP tools (6)

### `get_capabilities` (~38 tokens)

Get capabilities

What Car Rental Brain measures, how fresh it is, and which airports/countries are covered. Use first when unsure whether a place is covered.

Output parameters:

- `airports_measured` (integer)
- `countries` (array)
- `error` (string)
- `latest_measurement` (string)
- `note` (string)
- `tools` (array)

### `list_airports` (~56 tokens)

List airports

Airports we measure, with the typical rental price per day. Filter by country. Use to find an airport id or to list what is covered in a country.

Input parameters:

- `country` (string): Optional country, e.g. 'Portugal'

Output parameters:

- `airports` (array)
- `error` (string)
- `note` (string)

### `airport_costs` (~153 tokens)

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. Use when someone asks what car hire really costs at one airport, or about deposits, fees or desk hours there.

Input parameters:

- `airport` (string, required): Airport id, IATA code or name, e.g. 'faro', 'FAO', 'Faro Airport'
- `month` (string): Optional pick-up month YYYY-MM
- `trip_days` (integer): Optional trip length in days

Output parameters:

- `airport` (string)
- `basis` (object)
- `by_pickup_month` (array|null)
- `country` (string)
- `currency` (string)
- `deposit` (object)
- `desk_hours` (object)
- `error` (string)
- `iata` (string)
- `note` (string)
- `payment` (object)
- `price_per_day_7_day_hire` (object)
- `report_url` (string)
- `search_link` (string)
- `second_driver` (object)

### `compare_airports` (~164 tokens)

Compare airports

Rank airports by real cost (car only / with driver / with cover), typical deposit, debit-card friendliness or late desk hours. Use for 'where in Spain is car hire cheapest in March?' or 'which airport is best for a debit card?'

Input parameters:

- `airports` (array): Optional list of airports
- `country` (string): Optional country to compare within
- `limit` (integer): How many airports to return (default 10).
- `month` (string): Optional pick-up month YYYY-MM (price sort uses that month)
- `sort_by` (string): What to rank by: price (car only), price_with_driver, price_with_cover, deposit (lowest first), debit (most debit-friendly), late_desk (open latest). Default price.

Output parameters:

- `airports` (array)
- `error` (string)
- `note` (string)
- `sorted_by` (string)

### `supplier_terms` (~104 tokens)

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. Use when the person is choosing between suppliers at one airport or asks about a named supplier.

Input parameters:

- `airport` (string, required): Airport id, IATA code or name, e.g. 'faro', 'FAO', 'Faro Airport'
- `supplier` (string): Optional supplier name

Output parameters:

- `airport` (string)
- `error` (string)
- `note` (string)
- `search_link` (string)
- `suppliers` (array)

### `build_search_link` (~280 tokens)

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. Use whenever the person has dates and wants to see or book cars.

Input parameters:

- `age` (integer): Main driver's age in years (default 35). Under 25 or over 70 often costs more.
- `airport` (string): Airport id, IATA code or name, e.g. 'faro', 'FAO', 'Faro Airport'
- `automatic` (boolean): True for automatic gearbox only.
- `car_type` (string): Car size; omit for every size.
- `currency` (string): EUR, GBP, USD...
- `debit_card` (boolean): True if the driver has no credit card - only cars whose desk takes a debit card for the deposit.
- `dropoff_date` (string): YYYY-MM-DD
- `dropoff_time` (string): HH:MM
- `extra_driver` (boolean): True if a second driver will drive - their fee is then in every total.
- `pickup_date` (string): YYYY-MM-DD
- `pickup_time` (string): HH:MM
- `place` (string): Any city/place if not a measured airport
- `residence` (string): Two-letter country of residence, e.g. GB

Output parameters:

- `about_the_link` (string)
- `error` (string)
- `note` (string)
- `search_link` (string)

## Diagnostics

Captured diagnostic sections: TLS, DNSSEC, Authorisation, Transports. The full working is on the page: https://verifymcp.io/servers/com-carrentalbrain-car-rental-brain/app#diagnostics

## Score history

- 2026-10-23: 66
- 2026-10-22: 66
- 2026-10-21: 64
- 2026-10-20: 63
- 2026-10-19: 63

## Common questions

### What is the Car Rental Brain MCP server?

Car Rental Brain is an MCP server listed in the public MCP registry as com.carrentalbrain/car-rental-brain. Real cost of car hire at 120+ airports: second driver, cover, deposits, debit cards, desk hours. This page covers its hosted endpoint (https://app.carrentalbrain.com/mcp).

### Is the Car Rental Brain MCP server safe to use?

Car Rental Brain scores 66 out of 100 on VerifyMCP. 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 Car Rental Brain MCP server expose?

Car Rental Brain exposes 6 tools: get_capabilities, list_airports, airport_costs, compare_airports, supplier_terms, build_search_link. Their descriptions and schemas cost roughly 795 tokens of context every time the server is loaded.

### Does the Car Rental Brain MCP server require authentication?

No. We connected to Car Rental Brain without credentials and it answered, so anything it exposes is reachable by anyone who knows the address.

### Is the Car Rental Brain MCP server still maintained?

Car Rental Brain is still listed as active in the MCP registry. We last reached this channel on 23 October 2026. Those dates come from our own scans of the registry and the channel itself, not from anything the publisher announced.

## Links

- Remote endpoint: https://app.carrentalbrain.com/mcp
- Website: https://carrentalbrain.com/ai/
- Changelog RSS feed: https://verifymcp.io/servers/com-carrentalbrain-car-rental-brain/app.xml
- Changelog JSON feed: https://verifymcp.io/servers/com-carrentalbrain-car-rental-brain/app.json
- HTML version of this page: https://verifymcp.io/servers/com-carrentalbrain-car-rental-brain/app