diff --git a/modules/claude-code/cmd/claude-code/insteadof_test.go b/modules/claude-code/cmd/claude-code/insteadof_test.go
index 9ac5a4d37..405ca61cc 100644
--- a/modules/claude-code/cmd/claude-code/insteadof_test.go
+++ b/modules/claude-code/cmd/claude-code/insteadof_test.go
@@ -109,7 +109,9 @@ func TestTheMeshsToolsAreReadFromTheBus(t *testing.T) {
 		t.Errorf("replacements: %s", got)
 	}
 	t.Run("the again tool answers the operator and the healers only", func(t *testing.T) {
-		for caller, refused := range map[string]bool{"person.jochen": false, "shanks.mesh-healers": false, "shanks.mesh-config": true} {
+		// An operator's session through the mesh MCP server is proved as its machine's tool runner (issue 627, issue 1966).
+		for caller, refused := range map[string]bool{"person.jochen": false, "shanks.node-tools": false, "shanks.mesh-healers": false,
+			"shanks.mesh-config": true} {
 			if err := seatlist.Refusal("claude_code_seat_list_again", seatListAgainCallers, caller); (err != nil) != refused {
 				t.Errorf("%s: refused=%v, err %v", caller, refused, err)
 			}
diff --git a/modules/claude-code/cmd/claude-code/main.go b/modules/claude-code/cmd/claude-code/main.go
index af9c534ff..53a18a1a0 100644
--- a/modules/claude-code/cmd/claude-code/main.go
+++ b/modules/claude-code/cmd/claude-code/main.go
@@ -667,8 +667,10 @@ func refusals(n int) string {
 	return fmt.Sprintf(" (after %d refusal(s))", n)
 }
 
-// seatListAgainCallers may read the seat list again: every operator's session and the healers (ADR 0636 §7).
-var seatListAgainCallers = []string{stdio.AnyPerson, "mesh-healers"}
+// seatListAgainCallers may read the seat list again: every operator's session and the healers (ADR 0636 §7). A call through
+// the mesh MCP server is proved only as its machine's tool runner (<node>.node-tools, issue 627), so node-tools stands for
+// an operator's session until a session is proved (issue 1966).
+var seatListAgainCallers = []string{stdio.AnyPerson, "node-tools", "mesh-healers"}
 
 // seatListTools are the seat list reader's two tools: what the list holds and what it waits for, and a read now. The
 // reader starts once the runtime serves, after the tools are listed, so each tool finds it when it is called.
diff --git a/modules/mesh-conditions/cmd/mesh-conditions/keeper.go b/modules/mesh-conditions/cmd/mesh-conditions/keeper.go
index 178234acb..006aac7aa 100644
--- a/modules/mesh-conditions/cmd/mesh-conditions/keeper.go
+++ b/modules/mesh-conditions/cmd/mesh-conditions/keeper.go
@@ -20,6 +20,7 @@ import (
 	assignerclient "git.novox.be/novox/mesh-contracts/go/clients/meshmoduleassignerclient"
 	mesh "git.novox.be/novox/mesh-contracts/go/seats/meshmoduleassigner"
 	stdio "git.novox.be/novox/mesh-sdk/go"
+	"git.novox.be/novox/mesh-sdk/go/buscompose"
 	"git.novox.be/novox/mesh-sdk/go/motion"
 
 	cc "git.novox.be/novox/mesh-contracts/health-and-repair/go/clients/meshconditionsclient"
@@ -65,7 +66,10 @@ var Observers = []string{watchmanModule, selfCheckModule, healersModule, assigne
 	// readers' of the indexer's and the assigner's state (the registry milestone's join).
 	builder, indexer, "mesh-delivery-checker", "mesh-delivery-teller", "mesh-delivery-view", enrolment,
 	// The tool runner's and claude-code's own first views (views.UnansweredFinding in their findings, ADR 0615 §6).
-	"node-tools", "claude-code"}
+	"node-tools", "claude-code",
+	// The node-engine's: a node that has read no seat list five minutes after its start, seat-list-unread (ADR 0636 §1;
+	// issue 1966: written on ace and raised by nobody).
+	buscompose.EngineModule}
 
 // The other states it reads, as `<module>.<name>`.
 const (
diff --git a/modules/mesh-conditions/cmd/mesh-conditions/keeper_test.go b/modules/mesh-conditions/cmd/mesh-conditions/keeper_test.go
index 1b70ecd83..80b893b05 100644
--- a/modules/mesh-conditions/cmd/mesh-conditions/keeper_test.go
+++ b/modules/mesh-conditions/cmd/mesh-conditions/keeper_test.go
@@ -334,8 +334,9 @@ func TestEveryControllerKindHasItsHome(t *testing.T) {
 	// Each module that writes a reader's unanswered first view (ADR 0615 §6), or that a delivery part's consumer stopped
 	// hearing, is read: the delivery parts and the tool runner by name (other repositories), and every catalogue module
 	// whose code writes a views finding, found in the catalogue's tree, so a new writer cannot go unobserved.
+	// And the node-engine, whose node writes seat-list-unread when it has read no seat list (ADR 0636 §1, issue 1966).
 	readers := []string{watchman, "mesh-delivery-teller", enrolment, builder, "mesh-delivery-checker", "mesh-delivery-view",
-		indexer, assignerModule, configModule, vaultModule, gitea, "node-tools"}
+		indexer, assignerModule, configModule, vaultModule, gitea, "node-tools", "mesh-host"}
 	readers = append(readers, viewFindingWriters(t, "../../..")...)
 	for _, reader := range readers {
 		if !slices.Contains(Observers, reader) {
diff --git a/modules/mesh-conditions/module.json b/modules/mesh-conditions/module.json
index af7ed4ac5..f6803f865 100644
--- a/modules/mesh-conditions/module.json
+++ b/modules/mesh-conditions/module.json
@@ -34,6 +34,7 @@
     "mesh-enrolment.findings",
     "node-tools.findings",
     "claude-code.findings",
+    "mesh-host.findings",
     "mesh-healers.attempts",
     "node-engine.have"
   ],