diff --git a/src/skills/workshop/service-evaluation.test.ts b/src/skills/workshop/service-evaluation.test.ts
index 2c8c99fc9a13..c47d9fe4baad 100644
--- a/src/skills/workshop/service-evaluation.test.ts
+++ b/src/skills/workshop/service-evaluation.test.ts
@@ -759,6 +759,61 @@ describe("Skill Workshop proposal evaluation", () => {
     });
   });
 
+  it("does not split surrogate pairs when bounding evaluator text", async () => {
+    const workspaceDir = await tempDirs.make("openclaw-skill-evaluation-surrogate-");
+    const proposal = await proposeCreateSkill({
+      workspaceDir,
+      agentId: "main",
+      name: "Surrogate Bounds",
+      description: "Bound evaluator text without splitting surrogates",
+      content: "# Surrogate Bounds\n",
+    });
+    hookMocks.evaluate.mockResolvedValue([
+      {
+        evaluatorId: "emoji-bounds",
+        pluginId: "evaluation-tests",
+        status: "completed",
+        result: {
+          summary: `${"s".repeat(7_999)}🙂`,
+          decisionReason: `${"r".repeat(1_999)}🙂`,
+          metrics: { note: `${"m".repeat(3_999)}🙂` },
+        },
+      },
+      {
+        evaluatorId: "emoji-error",
+        pluginId: "evaluation-tests",
+        status: "error",
+        error: `${"e".repeat(1_999)}🙂`,
+      },
+    ]);
+
+    const evaluated = await evaluateSkillProposal({
+      workspaceDir,
+      agentId: "main",
+      proposalId: proposal.record.id,
+      expectedRevisionHash: proposal.revisionHash,
+    });
+
+    expect(evaluated.evaluation.outcomes).toEqual([
+      {
+        evaluatorId: "emoji-bounds",
+        pluginId: "evaluation-tests",
+        status: "completed",
+        result: {
+          summary: "s".repeat(7_999),
+          decisionReason: "r".repeat(1_999),
+          metrics: { note: "m".repeat(3_999) },
+        },
+      },
+      {
+        evaluatorId: "emoji-error",
+        pluginId: "evaluation-tests",
+        status: "error",
+        error: "e".repeat(1_999),
+      },
+    ]);
+  });
+
   it("rejects evaluator results that exceed the aggregate persistence budget", async () => {
     const workspaceDir = await tempDirs.make("openclaw-skill-evaluation-size-budget-");
     const proposal = await proposeCreateSkill({
diff --git a/src/skills/workshop/service-evaluation.ts b/src/skills/workshop/service-evaluation.ts
index 6d677f5ac379..f34c2e3c19b1 100644
--- a/src/skills/workshop/service-evaluation.ts
+++ b/src/skills/workshop/service-evaluation.ts
@@ -1,5 +1,6 @@
 import { randomUUID } from "node:crypto";
 import { normalizeOptionalString } from "@openclaw/normalization-core/string-coerce";
+import { truncateUtf16Safe } from "@openclaw/normalization-core/utf16-slice";
 import type {
   PluginHookSkillEvaluationFinding,
   PluginHookSkillProposalEvaluateResult,
@@ -346,18 +347,19 @@ function normalizeMetrics(
     ) {
       return undefined;
     }
-    normalized[key] = typeof value === "string" ? value.slice(0, 4_000) : value;
+    normalized[key] = typeof value === "string" ? truncateUtf16Safe(value, 4_000) : value;
   }
   return normalized;
 }
 
 function boundedRequired(value: string, maxLength: number, fallback: string): string {
   const normalized = normalizeOptionalString(value) ?? fallback;
-  return normalized.slice(0, maxLength);
+  return truncateUtf16Safe(normalized, maxLength);
 }
 
 function boundedOptional(value: string | undefined, maxLength: number): string | undefined {
-  return normalizeOptionalString(value)?.slice(0, maxLength);
+  const normalized = normalizeOptionalString(value);
+  return normalized === undefined ? undefined : truncateUtf16Safe(normalized, maxLength);
 }
 
 function storeOptions(env?: NodeJS.ProcessEnv) {