Manage Extensions & MCP
Open Settings → Extensions.
Locus supports MCP tools, resources, prompts, long-running tasks, progress, safe structured input, OAuth, remote HTTPS servers, and—where the build allows it—local stdio servers.
Add a server safely
- Add a catalog entry or a reviewed server definition.
- Connect it and complete authentication.
- Inspect every exposed capability.
- Allow only the profiles and tool classes that need it.
- Test with a read-only request before enabling mutations.
Remote MCP URLs must use HTTPS. OAuth uses PKCE, an exact callback, state verification, bounded registration metadata, and a verified authorization origin. Credential-shaped form fields are refused.
The bundled GitHub preset uses GitHub App device flow when the release is configured for it. Locus validates the account, stores tokens in Keychain, refreshes them, and keeps personal-token fallback for deployments that need it.
Optional plugin screens
Locus supports optional plugin screens. After installing a compatible plugin and reviewing its screen capabilities, choose Open in Extensions or use the Work menu.
Screen capabilities control what a plugin can display and open; native conversations retain their existing account and tool permissions. Plugin windows keep the project they opened in when the selected central chat changes.
Social Studio is a separately downloaded publishing plugin available through the marketplace and opened from Work. Its package owns its interface, accounts, and project data; the publishing interface is no longer built into Locus.
Agent Worlds is developed separately and is not bundled in Locus 4.1. The 4.1 host release supplies no Agent-World.zip, and legacy world packages are incompatible with its world bridge. Read Agent Worlds compatibility before attempting an installation. The world bridge's version is separate from the generic plugin-panel protocol used by Social Studio.
Per-profile policy
Read-only profiles receive only allowed read capabilities. Mutating tools require a write-capable route and the ordinary permission loop. Background MCP tasks persist their remote identifier, progress, cancellation, and terminal state so a reconnect can resume supervision without rerunning the task.
Treat every extension as code and every remote response as external data. Review the server, its scopes, and its destination before granting access.