diff --git a/packages/sdk/src/internal/providers/bailian/mapper.ts b/packages/sdk/src/internal/providers/bailian/mapper.ts
index 9802bbe..462c234 100644
--- a/packages/sdk/src/internal/providers/bailian/mapper.ts
+++ b/packages/sdk/src/internal/providers/bailian/mapper.ts
@@ -290,19 +290,18 @@ export function mapAgent(
 		}
 	}
 
-	// Skills
-	if (refs.skill_ids.length) {
-		body.skills = refs.skill_ids.map((s) => ({
-			// Bailian's SkillType enum is "customer" | "official"; map the
-			// resolver's generic "custom" sentinel to "customer".
-			type: s.type === "custom" ? "customer" : s.type,
-			skill_id: s.skill_id,
-			// Bailian composes `{skill_id}@{version}` internally and rejects
-			// entries without a version. Prefer explicit external references, then
-			// the latest active remote version, then the common initial version.
-			version: s.version ?? skillVersions?.[s.skill_id] ?? "1.0",
-		}));
-	}
+	// Skills are an explicit replacement set. Keep an empty array in the full update
+	// payload so removing the last binding has the same declarative meaning everywhere.
+	body.skills = refs.skill_ids.map((s) => ({
+		// Bailian's SkillType enum is "customer" | "official"; map the
+		// resolver's generic "custom" sentinel to "customer".
+		type: s.type === "custom" ? "customer" : s.type,
+		skill_id: s.skill_id,
+		// Bailian composes `{skill_id}@{version}` internally and rejects
+		// entries without a version. Prefer explicit external references, then
+		// the latest active remote version, then the common initial version.
+		version: s.version ?? skillVersions?.[s.skill_id] ?? "1.0",
+	}));
 
 	return body;
 }
diff --git a/packages/sdk/src/internal/providers/qoder/mapper.ts b/packages/sdk/src/internal/providers/qoder/mapper.ts
index b4f3bf0..3bf2113 100644
--- a/packages/sdk/src/internal/providers/qoder/mapper.ts
+++ b/packages/sdk/src/internal/providers/qoder/mapper.ts
@@ -466,13 +466,12 @@ export function mapAgent(
 		}
 	}
 
-	// Skills
-	if (refs.skill_ids.length) {
-		body.skills = refs.skill_ids.map((s) => ({
-			type: s.type === "official" ? "qoder" : s.type,
-			skill_id: s.skill_id,
-		}));
-	}
+	// Skills are an explicit replacement set. Qoder agent updates use merge semantics,
+	// so omitting this field would retain remote bindings when the declaration is `skills: []`.
+	body.skills = refs.skill_ids.map((s) => ({
+		type: s.type === "official" ? "qoder" : s.type,
+		skill_id: s.skill_id,
+	}));
 
 	return body;
 }
diff --git a/packages/sdk/tests/unit/bailian.test.ts b/packages/sdk/tests/unit/bailian.test.ts
index b1312f0..2cbfe6e 100644
--- a/packages/sdk/tests/unit/bailian.test.ts
+++ b/packages/sdk/tests/unit/bailian.test.ts
@@ -222,6 +222,11 @@ describe("Bailian mapAgent", () => {
 		expect(body.skills).toEqual([{ type: "customer", skill_id: "skill_abc", version: "1.0" }]);
 	});
 
+	test("keeps an explicit empty skill replacement set", () => {
+		const body = mapAgent("helper", minimalDecl, emptyRefs) as Record<string, unknown>;
+		expect(body.skills).toEqual([]);
+	});
+
 	test("injects agents metadata when projectName provided", () => {
 		const body = mapAgent("helper", minimalDecl, emptyRefs, undefined, "my-project") as Record<string, unknown>;
 		const meta = body.metadata as Record<string, string>;
diff --git a/packages/sdk/tests/unit/qoder-examples.test.ts b/packages/sdk/tests/unit/qoder-examples.test.ts
index 2691205..02d2655 100644
--- a/packages/sdk/tests/unit/qoder-examples.test.ts
+++ b/packages/sdk/tests/unit/qoder-examples.test.ts
@@ -97,6 +97,7 @@ test("qoder agent mapper preserves declared tool permission policies", () => {
 			],
 		},
 	]);
+	expect(body.skills).toEqual([]);
 });
 
 test("qoder permission overrides are case- and separator-insensitive", () => {