MCP connection controls

These controls select servers already available through the active engine inventory. Configure server definitions and authentication using the supported native engine configuration and Cloud MCP assignment paths; there is no separate general-purpose MCP catalog editor in the admin UI.

Custom servers in Slack Settings

Open ⚙️ Settings on a reply, choose MCPs, then find Custom MCP servers.

• This conversation contains custom-<name> servers shared by runs here. Channel managers and administrators can add, update and remove them; authority is checked again when saving.
• Yours contains your personal my-<name> servers. Only runs you start receive these, including your runs in other conversations. Other people do not see your personal list.

Choose Add or update, enter a name and public HTTPS server URL, then enter the Bearer token in the private modal. For an existing name, leave the token blank to keep it or enter a new token to replace it. Stored tokens are never prefilled or revealed; the list shows only their last four characters. Each scope holds up to five servers. OAuth-only servers use Composio instead.

Saving shows progress while the gateway checks the public address and your current access, then returns to the existing MCPs page, including after repeated updates. Local field errors remain inline. If a remote check fails or times out, Try again opens a fresh form; re-enter the token because its draft was cleared. Timed-out checks do not save later. Remove asks for confirmation and revokes that server’s live relay access. New runs receive the saved list; Lean runs receive no custom servers. Claude and Codex use the same scoped connections.

Admins can also manage these servers in the admin UI under the conversation’s Connections or the person’s Personal MCP servers. Custom servers are separate from the engine inventory and Cloud MCP selection controls below. Never paste a token into chat or a project MCP settings file.

list_available_mcps

Discover the current engine’s host-configured MCP inventory.

Arguments: none.

Authority and scope: Current admitted conversation and active engine.

Result: Server names and offline indicators.

Restrictions: Codex discovery uses the channel authentication scope when codexAuthSource is channel. Does not activate servers or prove account ownership.

list_channel_mcps

Show optional MCP selections for the active engine.

Arguments: none.

Authority and scope: Current conversation, active engine.

Result: Selected server names or a no-extra-servers message.

Restrictions: Engine-specific selection; built-in gateway and credential-backed connections are separate from this list.

add_channel_mcps

Allow configured named servers in this conversation.

Argument	Required	Meaning and default
names	Yes	Array of server names from list_available_mcps.

Authority and scope: Channel manager or administrator; normal control-plane approval policy.

Result: New selections and unknown/refused names.

Restrictions: Matches names case-insensitively. Only discovered servers with a supported persistable definition are saved. Conversation must exist; applies on next message. Does not grant arbitrary writes on the server.

remove_channel_mcps

Remove the active engine’s optional selections.

Argument	Required	Meaning and default
names	Yes	Array of server names, matched case-insensitively.

Authority and scope: Channel manager or administrator; normal control-plane approval policy.

Result: Removed count and remaining allowed names.

Restrictions: Does not remove built-in controls or credentials. Other engines’ separate selections remain. Applies next message.

Related guides

MCP integrations, server configuration, engine capabilities, and connected accounts.