diff --git a/checks/manifests/go.mod b/checks/manifests/go.mod
new file mode 100644
index 00000000..6fbb4f39
--- /dev/null
+++ b/checks/manifests/go.mod
@@ -0,0 +1,5 @@
+module checks/manifests
+
+go 1.26.0
+
+require git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261030181247-4c1384faefa0
diff --git a/checks/manifests/go.sum b/checks/manifests/go.sum
new file mode 100644
index 00000000..fc5109a2
--- /dev/null
+++ b/checks/manifests/go.sum
@@ -0,0 +1,2 @@
+git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261030181247-4c1384faefa0 h1:t04baH2Xz/NUsOEV3ctKY59XjiY5WmEuststvH+XeOs=
+git.novox.be/novox/mesh-sdk/go v0.1.14-0.20261030181247-4c1384faefa0/go.mod h1:ouERNpZizzwZ0HLEtAypsY9FR20FyUgUYRni6J7kVCY=
diff --git a/checks/manifests/main.go b/checks/manifests/main.go
new file mode 100644
index 00000000..9658b260
--- /dev/null
+++ b/checks/manifests/main.go
@@ -0,0 +1,61 @@
+// Package manifests judges every module's manifest as the node-engine reads it, and the catalogue as one shelf: each
+// modules/*/module.json through mesh-sdk's ParseManifestWith against the predefined.json at the root, with its templates
+// read from the tree beside it (WithTemplatesFrom), then the rules between manifests (CatalogueProblems,
+// IdentityProblems, DataProblems).
+//
+// Why it is here (issue 774): on 2026-10-30 mesh-catalog ca8d6f33 gave power's bar item two attributes its bar places
+// by none of. ParseManifest refuses that, and every node-engine refused to compose at 19:13; no check of the pull
+// request had parsed the manifest. That judgement was mesh-controller's `module check`, which the merge gate ran over
+// every manifest before the checker moved to mesh-delivery; the checker runs this repository's Go tests and the
+// composition, and no test parsed a manifest whole. This one does, in the same functions the nodes use.
+package manifests
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+	"sort"
+
+	"git.novox.be/novox/mesh-sdk/go/catalogue"
+)
+
+// Problems is what is wrong with the manifests under root/modules, one line each: a manifest the mesh refuses, named by
+// its path, then the rules between the manifests that parse.
+func Problems(root string) ([]string, error) {
+	files, err := filepath.Glob(filepath.Join(root, "modules", "*", "module.json"))
+	if err != nil {
+		return nil, err
+	}
+	sort.Strings(files)
+	list, err := catalogue.ReadPredefined(root)
+	if err != nil {
+		return nil, err
+	}
+	var out []string
+	shelf := catalogue.Shelf{}
+	for _, f := range files {
+		raw, err := os.ReadFile(f)
+		if err != nil {
+			return nil, err
+		}
+		rel, _ := filepath.Rel(root, f)
+		m, err := catalogue.ParseManifestWith(raw, list)
+		if err == nil {
+			m, err = catalogue.WithTemplatesFrom(m, filepath.Dir(f))
+		}
+		if err != nil {
+			out = append(out, fmt.Sprintf("%s: %v", rel, err))
+			continue
+		}
+		if _, twice := shelf[m.Module]; twice {
+			out = append(out, fmt.Sprintf("%s: %s was already given; two manifests name one module", rel, m.Module))
+			continue
+		}
+		shelf[m.Module] = m
+	}
+	between := catalogue.CatalogueProblems(shelf)
+	between = append(between, catalogue.IdentityProblems(shelf, catalogue.DefaultLongestMachine)...)
+	between = append(between, catalogue.DataProblems(shelf)...)
+	sort.Strings(between)
+	return append(out, between...), nil
+}
diff --git a/checks/manifests/main_test.go b/checks/manifests/main_test.go
new file mode 100644
index 00000000..49ba2ff6
--- /dev/null
+++ b/checks/manifests/main_test.go
@@ -0,0 +1,51 @@
+package manifests
+
+import (
+	"os"
+	"path/filepath"
+	"strings"
+	"testing"
+)
+
+// Every manifest of the catalogue is one the nodes can use, and the catalogue holds together as one shelf. A row is a
+// manifest written into a catalogue of its own: power's bar item as mesh-catalog ca8d6f33 gave it (issue 774) is
+// refused naming the attribute, and the same item without it passes.
+func TestEveryManifestIsOneTheNodesCanUse(t *testing.T) {
+	for _, row := range []struct {
+		name, attributes, refused string
+	}{
+		{name: "the bar places by bar and place", attributes: `"bar":"bottom","place":"status","order":"45"`},
+		{name: "an attribute the bar places by none of (ca8d6f33)",
+			attributes: `"bar":"bottom","place":"status","order":"45","shows":"state","state":"power.draw"`,
+			refused:    `"shows" is none of them`},
+	} {
+		root := t.TempDir()
+		dir := filepath.Join(root, "modules", "bar-user")
+		if err := os.MkdirAll(filepath.Join(dir, "files"), 0o755); err != nil {
+			t.Fatal(err)
+		}
+		manifest := `{"module":"bar-user","version":"1","moved":true,` +
+			`"build":{"artifacts":[{"name":"files","kind":"archive","from":"files"}]},` +
+			`"items":[{"collection":"contribution:node-bar:block","attributes":{` + row.attributes + `},"template":"files/bar"}]}`
+		for path, body := range map[string]string{"module.json": manifest, "files/bar": "{\"shows\":\"command\"}\n"} {
+			if err := os.WriteFile(filepath.Join(dir, path), []byte(body), 0o644); err != nil {
+				t.Fatal(err)
+			}
+		}
+		got, err := Problems(root)
+		if err != nil {
+			t.Fatal(err)
+		}
+		joined := strings.Join(got, "\n")
+		if (row.refused == "") != (len(got) == 0) || !strings.Contains(joined, row.refused) {
+			t.Errorf("%s: refused %q, want %q", row.name, joined, row.refused)
+		}
+	}
+	real, err := Problems(filepath.Join("..", ".."))
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(real) != 0 {
+		t.Fatalf("the catalogue holds manifests the nodes cannot use:\n%s", strings.Join(real, "\n"))
+	}
+}
diff --git a/checks/manifests/reads-outside b/checks/manifests/reads-outside
new file mode 100644
index 00000000..e0af3e80
--- /dev/null
+++ b/checks/manifests/reads-outside
@@ -0,0 +1,4 @@
+# What these tests read outside their package, as paths from the repository's root (issue 1936).
+# every module's directory (its manifest and the templates beside it), and the list of predefined keys.
+modules
+predefined.json