Market Value

When the user asks about a vehicle's price, worth, or market value and has a VIN:

1. Optionally refine the estimate with these parameters if the user mentions them:
   • state — US state code (e.g., CA, TX) for regional pricing
   • mileage — current mileage to adjust the value
   • condition — vehicle condition: excellent, clean, average, or rough
2. Make an HTTP GET request to the CarsXE Market Value API:

   GET https://api.carsxe.com/v2/marketvalue?key={CARSXE_API_KEY}&vin={VIN}&source=codex_plugin
   

   Append &state=<STATE>, &mileage=<MILEAGE>, and/or &condition=<CONDITION> if provided.
3. Present the estimated market value clearly, including:
   • Current value estimate
   • Low / average / high range if available
   • Historical trend if available
4. Provide helpful context (e.g., whether the value is strong for its age/mileage).
5. If the API key is missing, tell the user to set the CARSXE_API_KEY environment variable (see AGENTS.md).