# Open Hood: usage guide

Built from publicly available information. Not monetized; no company pays to appear.

Open Hood maps 120 companies that sell technology to US car dealers into 11 sections. Each company appears once, in its main business. When its own website shows a product in another section, that section is listed with the source page. Pages were read on 2026-10-29.

## What a result means

- A placement means the company's own website describes that product. It is not a rating, a ranking or an endorsement, and no company pays to appear.
- An empty "alsoSellsIn" list means no other section was found on the company's site. It does not prove the company sells nothing else.
- Products change. Cite the source link and the checked date, and tell the user to confirm on the source page.

## Sections

- `platforms`: Platforms & OEM partners
- `systems`: Dealer systems
- `data`: Customer data
- `web`: Websites & online retailing
- `inventory`: Inventory & listings
- `ai`: AI agents & search
- `ads`: Advertising
- `reviews`: Reviews & reputation
- `measurement`: Calls & attribution
- `credit`: Credit & F&I
- `service`: Service & parts

## JSON API

All routes are GET, read-only and need no key. Requests are rate limited; on 429, wait for Retry-After.

- `https://openhood.co/api/health`: service status and counts.
- `https://openhood.co/api/sections`: sections and subcategories with vendor ids.
- `https://openhood.co/api/vendors?section=ai&q=voice`: vendors in a section (main business or also sells in), optionally filtered by words.
- `https://openhood.co/api/vendors/{id}`: one vendor with its sources.
- `https://openhood.co/api/additional?section=ai`: companies not on the main map.

Example: `curl "https://openhood.co/api/vendors?section=reviews"`

## MCP

POST JSON-RPC 2.0 to `https://openhood.co/mcp` with Content-Type: application/json. Supported protocol versions: 2025-06-18, 2025-03-26, 2024-11-05. Send initialize, then notifications/initialized, then tools/list. Tools, all read-only: list_sections, search_vendors (query, section), get_vendor (id), list_additional_vendors (section). No resources, prompts, sessions or subscriptions.

## Additional vendors

`https://openhood.co/api/additional?section=ai` lists companies that sell to dealers but are not on the main map, each with a one-line description and a link to its own website. MCP tool: list_additional_vendors (section). These are listed, not placed or ranked.

## Not yet available

Buyer checklists, verified dealer ratings and a private stack check are planned and not yet live. Do not describe them as available.