# Sinter

> Sinter quotes and 3D prints parts (FDM: PLA+, PETG, ASA, PC, TPU, nylon, PPS-CF and carbon-fiber grades, or a custom material) through a REST API for AI agents and scripts. Upload a STEP, STL, OBJ or 3MF model, get manufacturability findings and a quote with two lead times, accept it, and track the order.

Base URL: https://sinter.systems. Authenticate with a customer API key (`Authorization: Bearer sk_sinter_...`). No key yet: start a device login (`POST /v1/device/start`), have your user approve the code at https://sinter.systems/device, and poll `POST /v1/device/token` for the key. Accepting a quote is a purchase: it needs the `purchase` scope, which the account owner grants by turning on Allow purchases for the key or agent, and the user's approval of that purchase. Every order is paid by card first: accept returns a checkout link (HTTP 402) for a person to pay. Every quote needs a delivery price before it can be paid.

MCP server: https://quote.sinter.systems/mcp (Streamable HTTP). Remote clients sign in with OAuth: the user approves the connection on the Sinter site and decides whether to allow purchases. Agents can send an API key instead (`Authorization: Bearer sk_sinter_...`).

## Docs

- [Overview](https://sinter.systems/docs): What the API does, base URL, units and formats.
- [Quickstart](https://sinter.systems/docs/quickstart): API key or device login, then upload, quote, accept and track with curl.
- [Authentication](https://sinter.systems/docs/authentication): API keys, scopes (quotes, orders, purchase), device login and OAuth for MCP.
- [API reference](https://sinter.systems/docs/api): Every customer endpoint: parameters, request bodies and responses.
- [Materials and lead times](https://sinter.systems/docs/materials): Materials, availability and lead times, live from /v1/materials.
- [Statuses and errors](https://sinter.systems/docs/statuses): Quote, order, part and delivery statuses; HTTP errors and limits.
- [Rules for agents](https://sinter.systems/docs/agents): Purchases need Allow purchases and user approval; checkout links; polling.
- [MCP](https://sinter.systems/docs/mcp): Hosted MCP server at /mcp: connecting from Claude Code, Claude.ai and ChatGPT; tools.
- [Manufacturability](https://sinter.systems/docs/dfm-warnings): Geometry checks, repair warnings, feature locations and engineering review through the API and MCP.
- [Service specification](https://sinter.systems/docs/service-specification): Materials, geometry, quality, inspection requests and delivery expectations.

## API

- [OpenAPI schema](https://sinter.systems/docs/openapi.json): customer endpoints
- [Materials and lead times](https://sinter.systems/v1/materials): public catalog, JSON