MarketCheck (BYOK)

MarketCheck (BYOK) — connector documentation

• MCP endpoint: https://byok-marketcheck.connectorbay.com/mcp
• REST API: POST https://byok-marketcheck.connectorbay.com/v1/tools/{tool_name}, described by the OpenAPI 3.1 spec at https://byok-marketcheck.connectorbay.com/openapi.json
• Transport: Streamable HTTP, stateless, MCP specification 2025-06-18 or later
• Authentication: your own MarketCheck MarketCheck API key, sent in the X-Upstream-Key header of every request (never stored, logged or cached)
• Health: https://byok-marketcheck.connectorbay.com/health · Tool schemas: https://byok-marketcheck.connectorbay.com/tools.json
• Publisher: Unify Dynamics LLC · connectorbay.com/byok-marketcheck · agent@connectorbay.com

What MarketCheck (BYOK) is for

MarketCheck (BYOK) lets an AI assistant read your own MarketCheck data through the MarketCheck API with a key you supply (MarketCheck API key). Read-only: 8 tools (search_active_inventory, get_listing, decode_vin, get_market_days_supply, get_sales_statistics, list_popular_cars, search_oem_incentives, autocomplete_inventory_terms). The BYOK key travels with each request, is used for that one call only and is never stored, logged or cached; it is only ever sent to api.marketcheck.com. Unofficial connector by Unify Dynamics LLC: not affiliated with, endorsed by or sponsored by MarketCheck. MarketCheck and its logos are trademarks of their owners and are used only to say which service the connector works with.

Ask your assistant things like:

• "Find used Toyota RAV4s under 30000 within 25 miles of 90210"
• "Show MarketCheck listing 1FTFW1ET5DFC10312-abc123"
• "What vehicle is VIN 1FTFW1ET5DFC10312?"
• "What is the market days supply of 2022 Honda CR-V in ZIP 94025?"
• "What do used Ford F-150s typically sell for in Texas?"
• "Which used cars are most common in Florida right now?"

What it does

• search_active_inventory: Search active dealer car listings in the US and Canada by place, radius, make, model, year, price, mileage and condition; returns price, mileage, days on market, dealer and build details. Calls count against your MarketCheck plan.
• get_listing: Get one dealer car listing by its MarketCheck listing id: price, price change, mileage, days on market, seller, build and options. Calls count against your MarketCheck plan.
• decode_vin: Decode a VIN into year, make, model, trim, body, drivetrain, fuel, engine, dimensions and fuel economy. Calls count against your MarketCheck plan.
• get_market_days_supply: Get the market days supply for a vehicle (active cars divided by recent daily sales) with the active count and the number sold in the last 45 days. Calls count against your MarketCheck plan.
• get_sales_statistics: Get inferred sales statistics (count, price, mileage and days-on-market distributions) for a make, make-model, year-make-model, trim or VIN; give at least one of make, mm, ymm, ymmt or vin. Calls count against your MarketCheck plan.
• list_popular_cars: List the most common makes and models in current inventory for a market with price, mileage and days-on-market statistics (up to 50 rows nationally or per state, 25 per city). Calls count against your MarketCheck plan.
• search_oem_incentives: Search manufacturer incentive offers (cash back, APR, lease deals) for a make around a ZIP code, with offer type, amounts, term and validity dates. Calls count against your MarketCheck plan.
• autocomplete_inventory_terms: Suggest values (up to 50) for a field such as make, model, trim or ymm from the live inventory, to build valid filters for search_active_inventory. Calls count against your MarketCheck plan.

BYOK key

You bring your own MarketCheck MarketCheck API key (https://developers.marketcheck.com). Your assistant sends it in the X-Upstream-Key header with each request. ConnectorBay uses it for that one call only: it is never stored, logged or cached, never shown in an answer, and it is only sent to api.marketcheck.com over https, with no redirects followed. Create a key with the fewest permissions the tools need (read-only if the provider offers it), and revoke it at the provider whenever you like.

Data sources

• https://docs.marketcheck.com/docs/api/cars/inventory (the API this connector calls, with a BYOK key)

Live from the MarketCheck API (api.marketcheck.com) with a BYOK key; documentation: https://docs.marketcheck.com/docs/api/cars/inventory. Endpoints checked against that documentation on 2026-10-16.

What it is not

Unofficial connector by Unify Dynamics LLC: not affiliated with, endorsed by or sponsored by MarketCheck. MarketCheck and its logos are trademarks of their owners and are used only to say which service the connector works with. It is read-only: it never creates, changes, sends or deletes anything in your MarketCheck account.

Built for: Worldwide. Languages: English.

MarketCheck (BYOK) — Privacy Policy

Effective 24 October 2026. Unify Dynamics LLC ("we", "us"), Menlo Park, California.

What MarketCheck (BYOK) is. MarketCheck (BYOK) is a connector (an MCP server and REST API) that an AI assistant calls on your behalf to read your own MarketCheck data: Search US and Canadian vehicle inventory and read listing details, VIN decodes, market days supply, sales statistics, popular cars and OEM incentives with your own MarketCheck key. You bring your own MarketCheck MarketCheck API key; the assistant sends it to us with each request.

BYOK key. The key you supply is used to make the one MarketCheck call you asked for. Our application does not store it, write it to a log, put it in a cache, or share it. It is sent only to api.marketcheck.com, over https, and is removed from any text we return to you or your assistant. We do not follow redirects with your key. If MarketCheck rejects it, we say so without repeating it.

What we receive. The arguments of each tool call, the BYOK key (for that call only), the technical headers needed to serve the request (an IP address or a client identifier supplied by the assistant) and standard server logs. What MarketCheck receives. The request we make on your behalf, including the key and the arguments, under MarketCheck's own terms and privacy policy. MarketCheck acts at your direction and is the only recipient of the data of your request besides our hosting provider.

What we return. The answer MarketCheck gives for your request, trimmed to the fields the tool documents. We do not keep it: it is returned to your assistant and not stored, cached or used to train anything.

What we do not do. We do not build a profile, sell or share personal information, or keep your MarketCheck data. Rate-limit counters (a client identifier and timestamps) are held in memory for at most 24 hours. Hosting access logs (IP addresses, request paths and status codes) are kept for up to 30 days for security and abuse prevention; our application adds no request headers or bodies to them.

Sub-processors. MarketCheck (the API you call with a BYOK key, at your direction). Hosting: Vercel (United States regions).

Your rights. Because we store no personal data beyond short-lived logs, requests to access, correct or delete data are usually satisfied automatically; you can still contact agent@connectorbay.com and we will respond within 30 days. Revoke your key at MarketCheck at any time to end all access.

Children. MarketCheck (BYOK) is a general-audience service operated by the adult using the assistant, under MarketCheck's own age rules.

Changes. We will post changes here with a new effective date.

MarketCheck (BYOK) — Terms of Service

Effective 24 October 2026. These terms govern use of the MarketCheck (BYOK) connector ("the Service") operated by Unify Dynamics LLC ("we", "us").

1. The Service. MarketCheck (BYOK) provides: Search US and Canadian vehicle inventory and read listing details, VIN decodes, market days supply, sales statistics, popular cars and OEM incentives with your own MarketCheck key. It is accessed through an AI assistant or directly over MCP or HTTP, and is read-only.
2. Your own key, your own account. You must use your own MarketCheck credentials and only access data you are allowed to access. MarketCheck's terms apply to your use of MarketCheck; you are responsible for complying with them, including any rate limits and permitted uses. Do not share a key you do not own.
3. Independent. Unofficial connector by Unify Dynamics LLC: not affiliated with, endorsed by or sponsored by MarketCheck. MarketCheck and its logos are trademarks of their owners and are used only to say which service the connector works with.
4. No advice, no guarantees. Output is the data MarketCheck returns, lightly trimmed; it may be incomplete, delayed or changed by MarketCheck. Check important facts at the source.
5. Read-only. The Service does not create, change, send or delete anything in your MarketCheck account.
6. Acceptable use. Automated use within the published rate limits is welcome. Do not use the Service to access data you are not entitled to, to circumvent MarketCheck's controls, or to attack any system.
7. Availability. The Service is provided "as is" without warranty. We may change, limit or discontinue it at any time; MarketCheck may change or end its API at any time.
8. Data. Our Privacy Policy describes what we process. In short: the BYOK key is used for the one call and not stored or logged.
9. Pro keys. Optional ConnectorBay Pro API keys are issued at our discretion and are separate from your MarketCheck key.
10. Liability. To the fullest extent permitted by law, Unify Dynamics LLC is not liable for any loss arising from use of or reliance on the Service, including any action MarketCheck takes on your account. Our total liability is limited to US $100.
11. Governing law. California law; venue in San Mateo County, California.
12. Contact. Unify Dynamics LLC · agent@connectorbay.com · https://connectorbay.com/byok-marketcheck

MarketCheck (BYOK) support

Email agent@connectorbay.com. We answer within two business days.

• MCP endpoint: https://byok-marketcheck.connectorbay.com/mcp
• REST API: https://byok-marketcheck.connectorbay.com/openapi.json
• Live status: https://byok-marketcheck.connectorbay.com/health

When you report a problem, include the question you asked your agent, roughly when, and which agent you used (for example Claude, ChatGPT or Gemini). Never send us passwords, account numbers or ID numbers. MarketCheck (BYOK) never asks for them.