# Credentials (/docs/run/credentials)



Model credentials live in the Tenant vault. They never reach your app, the
agent loop, or the sandbox. Set them with `npx @nylorun/cli configure`, Studio
Model Settings, or the `.env` seed on first `nylorun start`. See
[Models](/docs/run/models).

## MCP credentials [#mcp-credentials]

{/* revisit after protocol 7 */}

Outbound MCP servers that need a URL-bound token take that credential from a
vault attached to the session:

```ts
await client.createSession({
  agentId: "assistant",
  ownerUserId: authenticatedUser.id,
  vaultIds: [vaultId],
});
```

Attach only vaults that belong to the same `ownerUserId` as the session. Reads
return metadata, never the secret. The Tenant model credential is not
attachable to a session.

Open source does not sign people in or store their secrets for you. Your app
owns identity; plug your own secret store into the session you open.

## Next step [#next-step]

<Cards>
  <Card title="MCP" description="Declare MCP servers on the agent." href="/docs/build/mcp" />

  <Card title="Serve your users" description="Act for a signed-in person." href="/docs/build#serve-your-users" />
</Cards>