diff --git a/crates/engine/src/commands/layer.rs b/crates/engine/src/commands/layer.rs
index 7be56a9e..11dcb4dc 100644
--- a/crates/engine/src/commands/layer.rs
+++ b/crates/engine/src/commands/layer.rs
@@ -1548,7 +1548,7 @@ pub fn specs() -> Vec<CommandSpec> {
             "Edit Text",
             [],
             None,
-            "{layer?, range?: [start, end] (characters; default all), text?, font?, style?, size?, fill?, stroke?, applyFill?, applyStroke?, strokeWidth?, tracking?, leading?: px|\"auto\", baselineShift? px, hScale? %, vScale? %, tsume? %, fauxBold?, fauxItalic?, allCaps?, smallCaps?, baseline?: normal|superscript|subscript, superscript?, subscript?, kerning?: metrics|optical|number, ligatures?, OpenType?: discretionaryLigatures?, contextualAlternates?, stylisticAlternates?, stylisticSets?: [1–20], ss01?…ss20?, swash?, titling?, ordinals?, fractions?, allSmallCaps?, figureStyle?: default|lining|oldStyle, figureWidth?: default|proportional|tabular, figures?, variations?: {tag: value} (variable font axes; null resets), justify?: left|center|right|justifyLeft|justifyCenter|justifyRight|justifyAll, indentLeft?, indentRight?, indentFirst?, spaceBefore?, spaceAfter?, direction?: ltr|rtl, composer?: everyLine|singleLine, hangingPunctuation?, strokeOverFill?, box?: [x,y,w,h]|null (layer space), vertical?}",
+            "{layer?, range?: [start, end] (characters; default all), text?, font?, style?, size?, fill?, stroke?, applyFill?, applyStroke?, strokeWidth?, tracking?, leading?: px|\"auto\", baselineShift? px, hScale? %, vScale? %, tsume? %, fauxBold?, fauxItalic?, allCaps?, smallCaps?, baseline?: normal|superscript|subscript, superscript?, subscript?, kerning?: metrics|optical|number, ligatures?, discretionaryLigatures? (OpenType), contextualAlternates?, stylisticAlternates?, stylisticSets?: [1–20], ss01?, ss02?, ss03?, ss04?, ss05?, ss06?, ss07?, ss08?, ss09?, ss10?, ss11?, ss12?, ss13?, ss14?, ss15?, ss16?, ss17?, ss18?, ss19?, ss20?, swash?, titling?, ordinals?, fractions?, allSmallCaps?, figureStyle?: default|lining|oldStyle, figureWidth?: default|proportional|tabular, figures?, variations?: {tag: value} (variable font axes; null resets), justify?: left|center|right|justifyLeft|justifyCenter|justifyRight|justifyAll, indentLeft?, indentRight?, indentFirst?, spaceBefore?, spaceAfter?, direction?: ltr|rtl, composer?: everyLine|singleLine, hangingPunctuation?, strokeOverFill?, box?: [x,y,w,h]|null (layer space), vertical?}",
             has_layers,
             set_text
         ),
diff --git a/crates/engine/src/tests_text_edit.rs b/crates/engine/src/tests_text_edit.rs
index d543fc9a..ef87bf86 100644
--- a/crates/engine/src/tests_text_edit.rs
+++ b/crates/engine/src/tests_text_edit.rs
@@ -259,3 +259,19 @@ fn fonts_lists_bundled_and_installed_families() {
     assert_eq!(crate::font_styles("NOTO SERIF"), styles);
     assert_eq!(crate::font_styles("No Such Family").len(), 5);
 }
+
+/// `layer.setText`'s schema lists every OpenType key as optional, so checked execution (control
+/// channel, MCP) accepts them and requires none (#520).
+#[test]
+fn set_text_schema_accepts_every_opentype_key_and_requires_none() {
+    let spec = crate::commands::find("layer.setText").unwrap();
+    let schema = crate::commands::params_schema(spec);
+    assert_eq!(schema["required"], json!([]));
+    for key in ["discretionaryLigatures", "ss01", "ss02", "ss20", "swash"] {
+        assert!(schema["properties"].get(key).is_some(), "{key} is not in the schema");
+    }
+    assert!(schema["properties"].get("OpenType").is_none());
+    let (mut s, t) = session("Office 1/2");
+    s.execute_checked("layer.setText", json!({"layer": t, "discretionaryLigatures": true, "ss02": true, "ss20": true})).unwrap();
+    assert!(doc(&s, t).style_at(0).opentype.stylistic_set(20));
+}