---
title: "Two endpoints"
description: "The run surface acts with tools, the Build surface authors the agents that act."
url: https://docs.spinrun.ai/build/endpoints
markdown_url: https://docs.spinrun.ai/build/endpoints.md
---

# Two endpoints

Spinrun exposes two MCP endpoints on the same origin, and they answer different questions.

* `https://spinrun.ai/mcp` — the run surface. Tools from the apps a workspace has connected: search for one, call it. This is what an agent uses to act.
* `https://spinrun.ai/mcp/build` — the Build surface. It authors the agents and workflows that later act: list, get, validate, put, delete, and start a test run. Its REST twin lives under `https://spinrun.ai/api/build`, with the same auth and the same documents.

A client installs each one separately. The dashboard's client pages and `spinrun gateway <client> --build` print the Build variant, and `spinrun install <client> --build` writes it beside the run entry under the key `spinrun-build`.

## Related [#related]

* [Authorization](https://docs.spinrun.ai/build/authorization.md)
* [Install](https://docs.spinrun.ai/install.md)
* [CLI: install](https://docs.spinrun.ai/cli/install.md)