diff --git a/examples/langchain-agent.ts b/examples/langchain-agent.ts
index 1797a16..5f4b9a2 100644
--- a/examples/langchain-agent.ts
+++ b/examples/langchain-agent.ts
@@ -21,6 +21,6 @@ const cl = new CommandLayer({
 
 const input = { prompt: "Summarize how receipts prove agent actions." };
 
-const result = await cl.wrap("chain.invoke", async () => chain.invoke(input));
+const result = await cl.wrap("attest", async () => chain.invoke(input));
 
-console.log(JSON.stringify(result.receipt, null, 2));
+process.stdout.write(JSON.stringify(result.receipt, null, 2) + "\n");
diff --git a/src/index.ts b/src/index.ts
index adc1cd9..f76516c 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -52,11 +52,28 @@ const TRUST_VERBS = [
 
 export type TrustVerb = (typeof TRUST_VERBS)[number];
 
+const TRUST_VERB_SET: ReadonlySet<string> = new Set(TRUST_VERBS);
+
 export function normalizeTrustVerb(verb: string): string {
   const prefix = `clas.${TRUST_FAMILY}.`;
   return verb.startsWith(prefix) ? verb.slice(prefix.length) : verb;
 }
 
+/**
+ * Normalize and validate a trust verb. Throws if the resulting short verb is
+ * not a member of the schema-defined TRUST_VERBS enum.
+ */
+function resolveAndValidateTrustVerb(verb: string): string {
+  const normalized = normalizeTrustVerb(verb);
+  if (!TRUST_VERB_SET.has(normalized)) {
+    throw new Error(
+      `Invalid trust verb "${verb}". Must be one of: ${TRUST_VERBS.join(", ")}. ` +
+      `Fully-qualified names like "clas.trust-verification.verify" are also accepted.`,
+    );
+  }
+  return normalized;
+}
+
 export class CommandLayer {
   private readonly config: {
     signer: string;
@@ -124,7 +141,9 @@ export class CommandLayer {
       typeof fnOrOptions === "function" ? {} : fnOrOptions.input ?? {};
 
     const startedMs = Date.now();
-    const normalizedVerb = normalizeTrustVerb(verb);
+    // Validate verb before running the wrapped function so callers get a
+    // synchronous, descriptive error rather than a non-schema-valid receipt.
+    const normalizedVerb = resolveAndValidateTrustVerb(verb);
     const startedAt = new Date().toISOString();
 
     try {
diff --git a/test/receipt.test.ts b/test/receipt.test.ts
index 187ee83..76b90ec 100644
--- a/test/receipt.test.ts
+++ b/test/receipt.test.ts
@@ -4,6 +4,7 @@ import { webcrypto } from "node:crypto";
 import { createServer, type IncomingMessage, type ServerResponse } from "node:http";
 
 import { CommandLayer } from "../src/index.js";
+import { validateTrustReceipt } from "../src/index.js";
 import { canonicalize } from "../src/canonicalize.js";
 import { canonicalPayloadFromReceiptInput } from "../src/receipt.js";
 
@@ -47,6 +48,35 @@ test("wrapping an action creates a receipt with required fields", async () => {
   assert.ok(result.receipt.execution.completed_at);
 });
 
+test("wrap produces a schema-valid receipt (round-trip)", async () => {
+  const cl = new CommandLayer({
+    signer: "verifyagent.eth",
+    keyId: "vC4WbcNoq2znSCiQ",
+    privateKeyPem: await generatePrivateKeyPem(),
+  });
+
+  const result = await cl.wrap("verify", {
+    input: { content: "hello world" },
+    run: async () => ({ approved: true }),
+  });
+
+  const validation = validateTrustReceipt(result.receipt);
+  assert.equal(validation.ok, true, `Receipt failed schema validation: ${validation.errors.join("; ")}`);
+});
+
+test("wrap rejects an unrecognized verb before running the wrapped function", async () => {
+  const cl = new CommandLayer({
+    signer: "verifyagent.eth",
+    keyId: "vC4WbcNoq2znSCiQ",
+    privateKeyPem: await generatePrivateKeyPem(),
+  });
+
+  await assert.rejects(
+    () => cl.wrap("summarize", async () => "should not run"),
+    /Invalid trust verb/,
+  );
+});
+
 test("signature is verifiable over raw canonical payload bytes", async () => {
   const { pem, publicKey } = await generateKeyPair();
 
@@ -56,7 +86,7 @@ test("signature is verifiable over raw canonical payload bytes", async () => {
     privateKeyPem: pem,
   });
 
-  const { receipt } = await cl.wrap("summarize", {
+  const { receipt } = await cl.wrap("authenticate", {
     input: { x: 1 },
     run: async () => ({ y: 2 }),
   });
@@ -92,7 +122,7 @@ test("wrap returns signed error receipt when wrapped agent throws", async () =>
     privateKeyPem: await generatePrivateKeyPem(),
   });
 
-  const result = await cl.wrap("summarize", {
+  const result = await cl.wrap("authenticate", {
     input: { content: "hello" },
     run: async () => {
       throw new Error("simulated failure");
@@ -105,6 +135,24 @@ test("wrap returns signed error receipt when wrapped agent throws", async () =>
   assert.equal(result.receipt.proof.alg, "ed25519");
 });
 
+test("error receipt is also schema-valid", async () => {
+  const cl = new CommandLayer({
+    signer: "verifyagent.eth",
+    keyId: "vC4WbcNoq2znSCiQ",
+    privateKeyPem: await generatePrivateKeyPem(),
+  });
+
+  const result = await cl.wrap("authenticate", {
+    input: { content: "hello" },
+    run: async () => {
+      throw new Error("simulated failure");
+    },
+  });
+
+  const validation = validateTrustReceipt(result.receipt);
+  assert.equal(validation.ok, true, `Error receipt failed schema validation: ${validation.errors.join("; ")}`);
+});
+
 test("fully-qualified trust capability verb normalizes to short verb", async () => {
   const cl = new CommandLayer({
     signer: "verifyagent.eth",
@@ -144,7 +192,7 @@ test("verification helper posts to verifierUrl", async () => {
     verifierUrl,
   });
 
-  const { receipt } = await cl.wrap("summarize", {
+  const { receipt } = await cl.wrap("verify", {
     input: { content: "hello" },
     run: async () => "hello",
   });