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Agent Fleet

Allow MCP servers as watch sources

Decide, for the whole tenant, whether members may make their own MCP servers a source for the watch tool (a watch source). Once allowed, sessions can be told about changes in systems Agent Fleet does not watch out of the box, such as a ticket queue or an in-house deploy tool.

How it works

Section titled “How it works”
What you do What happens on the members’ side
Leave it on “Block” (the initial state) No member can make a server a watch source, and registered sources do not run
Switch to “Allow” Members can turn “Watch source” on server by server
Switch back to “Block” Within five minutes every source in the tenant stops. Members’ registrations are kept

Once allowed, the workspace’s watch engine calls the servers members chose, at intervals. That puts code a member chose on the engine’s path, so it is off in every tenant until you allow it.

Switch it

Section titled “Switch it”
  1. Open Operations → “Watch sources” in Tenant settings
  2. Press “Allow” or “Block”. It is saved when you press it
"MCP servers as watch sources". Below the explanation, the Allow / Block switch, followed by a line on the current state

Allowing it changes nothing for anyone until a member chooses. Members turn on “Watch source” under Advanced → “Used by” for each server in ⚙ Settings → Connections → “MCP servers (used by sessions)”.

Each switch is recorded in the audit log as tenant.watch_sources, with enabled=true or enabled=false (Read the audit log). Only tenant administrators and the deployment administrator can switch it.

What allowing it does not change

Section titled “What allowing it does not change”
  • Only servers a member registered themselves can be sources. Servers you distribute to the tenant cannot
  • A source’s events reach only that member’s own sessions (or the member), as quoted data. They are not sent to other members, other workspaces or the Control Plane
  • The workspace calls a source with at most 20 subjects at a time, each subject at most once a minute, and at most 10 seconds per call
  • After five failures in a row, or 20 malformed replies in a row, the source pauses. It resumes when the member edits the server or enables it again
  • A local (stdio) server starts not in the Agent’s environment but in a reduced one (PATH, HOME, LANG, TMPDIR and the server’s own variables)

When you switch back to Block

Section titled “When you switch back to Block”
  • It reaches each workspace with the same five-minute fetch that distributed MCP servers use
  • A server marked as a source keeps its mark and pauses. It resumes when you allow it again
  • When the switch cannot be read, the workspace keeps the last answer it got. If it never got one, it runs nothing
Section titled “Related”