For AI assistants
Ask an assistant about a used Tesla and it can answer from the VIN, for free.
What the answer holds
- The battery pack or packs the car may have, with the capacity each had when new.
- The capacity a Tesla of this model and age normally still holds, as a range, where it is known.
- What that range does not say about this exact car.
- The link where the user gets Tesla’s own battery figure for this exact car.
It needs no account and no key, it never calls Tesla, and it never says how many cars stand behind a figure.
Ways in
| Way in | What it is |
|---|---|
| MCP server https://api.batteryfigures.com/mcp | One tool, preview_vin. Streamable HTTP, no sign-in. |
| JSON https://batteryfigures.com/check/{VIN}.json | The same answer over plain HTTP, for any assistant that can fetch a URL. |
| OpenAPI https://batteryfigures.com/openapi.json | The JSON answer described for tools and code. |
| llms.txt https://batteryfigures.com/llms.txt | The site in one file for language models. |
| Agent Skill https://batteryfigures.com/skills/tesla-battery-check/SKILL.md | When to use the preview and how to present it. |
The MCP server is listed in the official MCP registry as io.github.ZyberSE/batteryfigures.
What to ask
Give the assistant the VIN of the car and ask what it can tell you about its battery. An assistant that uses the preview tells you what is normal for the model at that age, and sends you to the lookup for this car’s own figure.
What it does not say
The free answer is what is normal for the model at this age. It is not this car’s measured battery health. That figure comes from Tesla through a lookup: see pricing for the cost and the sample report for what one returns.