diff --git a/forge/ee/routes/teamBroker/3rdPartyBroker.js b/forge/ee/routes/teamBroker/3rdPartyBroker.js
index e114ae662a..ac51c68577 100644
--- a/forge/ee/routes/teamBroker/3rdPartyBroker.js
+++ b/forge/ee/routes/teamBroker/3rdPartyBroker.js
@@ -447,10 +447,18 @@ module.exports = async function (app) {
             } else if (agent?.state === 'starting') {
                 // Another start is already launching the agent: starting is a no-op
                 reply.status(200).send({})
-            } else if (agent && agent.state !== 'running') {
-                await app.containers.sendBrokerAgentCommand(agent, 'start')
+            } else if (agent) {
+                // The agent is up. The stored 'running' state doesn't tell us whether
+                // it's actually collecting, so ask the agent. Only send start when it
+                // isn't connected (stopped via the API or after the 24h auto-shutdown),
+                // since start fully tears the agent down and reconnects it, which would
+                // take a healthy agent offline and drop in-flight messages.
+                const status = await app.containers.getBrokerAgentState(agent)
+                if (!status?.connected) {
+                    await app.containers.sendBrokerAgentCommand(agent, 'start')
+                }
                 reply.status(200).send({})
-            } else if (!agent) {
+            } else {
                 // Stays 'starting' until the driver has launched the agent, so a suspend
                 // arriving meanwhile is refused rather than missing a process it can't stop yet
                 const agent = await app.db.models.TeamBrokerAgent.create({
@@ -467,9 +475,6 @@ module.exports = async function (app) {
                 agent.state = 'running'
                 await agent.save()
                 reply.status(200).send({})
-            } else {
-                // Agent already running: starting is a no-op
-                reply.status(200).send({})
             }
         } else {
             if (request.broker.state === 'running') {
diff --git a/test/unit/forge/ee/routes/teamBroker/3rdPartyBroker_spec.js b/test/unit/forge/ee/routes/teamBroker/3rdPartyBroker_spec.js
index 17fd0368fa..826ef6894c 100644
--- a/test/unit/forge/ee/routes/teamBroker/3rdPartyBroker_spec.js
+++ b/test/unit/forge/ee/routes/teamBroker/3rdPartyBroker_spec.js
@@ -781,14 +781,47 @@ describe('3rd Party Broker API', function () {
             await app.db.models.TeamBrokerAgent.destroy({ where: { TeamId: app.team.id } })
         })
 
-        it('start replies when the team-broker agent is already running', async function () {
+        it('start resumes a team-broker agent that is up but no longer collecting', async function () {
+            // After a stop or the 24h auto-shutdown the agent stays recorded as running
+            // but is no longer connected, so switching the toggle on must re-issue the
+            // start command to resume collection.
+            const agent = await app.db.models.TeamBrokerAgent.create({ state: 'running', TeamId: app.team.id })
+            const getBrokerAgentState = sinon.stub(app.containers, 'getBrokerAgentState').resolves({ connected: false, error: null })
+            const sendBrokerAgentCommand = sinon.stub(app.containers, 'sendBrokerAgentCommand').resolves()
+            try {
+                const response = await app.inject({
+                    method: 'POST',
+                    url: `/api/v1/teams/${app.team.hashid}/brokers/team-broker/start`,
+                    cookies: { sid: TestObjects.tokens.bob }
+                })
+                response.statusCode.should.equal(200)
+                sendBrokerAgentCommand.calledOnce.should.be.true()
+                sendBrokerAgentCommand.firstCall.args[0].should.have.property('id', agent.id)
+                sendBrokerAgentCommand.firstCall.args[1].should.equal('start')
+            } finally {
+                sendBrokerAgentCommand.restore()
+                getBrokerAgentState.restore()
+            }
+        })
+
+        it('start leaves a team-broker agent that is already collecting alone', async function () {
+            // A connected agent is already collecting; sending it start would tear the
+            // broker down and reconnect, so this must stay a no-op.
             await app.db.models.TeamBrokerAgent.create({ state: 'running', TeamId: app.team.id })
-            const response = await app.inject({
-                method: 'POST',
-                url: `/api/v1/teams/${app.team.hashid}/brokers/team-broker/start`,
-                cookies: { sid: TestObjects.tokens.bob }
-            })
-            response.statusCode.should.equal(200)
+            const getBrokerAgentState = sinon.stub(app.containers, 'getBrokerAgentState').resolves({ connected: true, error: null })
+            const sendBrokerAgentCommand = sinon.stub(app.containers, 'sendBrokerAgentCommand').resolves()
+            try {
+                const response = await app.inject({
+                    method: 'POST',
+                    url: `/api/v1/teams/${app.team.hashid}/brokers/team-broker/start`,
+                    cookies: { sid: TestObjects.tokens.bob }
+                })
+                response.statusCode.should.equal(200)
+                sendBrokerAgentCommand.called.should.be.false()
+            } finally {
+                sendBrokerAgentCommand.restore()
+                getBrokerAgentState.restore()
+            }
         })
 
         it('stop replies when the team-broker agent is not running', async function () {