diff --git a/README.md b/README.md
index c4fab78..23f80ae 100644
--- a/README.md
+++ b/README.md
@@ -24,6 +24,9 @@ node bin/trace.mjs doctor
 node bin/trace.mjs validate examples/strands-forcing.json --json
 node bin/trace.mjs deliver examples/strands-forcing.json /tmp/loop-trace/demo.html --json
 # 用浏览器打开 /tmp/loop-trace/demo.html：T 切主题，E 导出 PNG
+
+# 管道友好：输入传 "-" 即可从 stdin 读 IR
+cat examples/strands-forcing.json | node bin/trace.mjs validate - --json
 ```
 
 零依赖回归测试：`npm test`（Node 内置 node:test，覆盖 doctor / validate / deliver / 坏样本拒绝）。
diff --git a/bin/trace.mjs b/bin/trace.mjs
index 092d7b1..fc056f0 100644
--- a/bin/trace.mjs
+++ b/bin/trace.mjs
@@ -10,6 +10,16 @@ function loadJson(p) {
   return JSON.parse(readFileSync(p, "utf8"));
 }
 
+// "-" streams the spec from stdin so agent pipelines can pipe IR directly:
+//   cat spec.json | node bin/trace.mjs validate - --json
+function readSpecRaw(inputPath) {
+  return inputPath === "-" ? readFileSync(0) : readFileSync(resolve(inputPath));
+}
+
+function specLabel(inputPath) {
+  return inputPath === "-" ? "<stdin>" : resolve(inputPath);
+}
+
 function validateSpec(spec) {
   const checks = [];
   const errors = [];
@@ -152,16 +162,24 @@ if (cmd === "doctor") {
   console.log(jsonOut ? JSON.stringify(out, null, 2) : "agent-loop-trace ready.");
 } else if (cmd === "validate") {
   const [input] = args;
-  const spec = loadJson(resolve(input));
+  if (!input) {
+    console.error("usage: trace.mjs validate <spec.json | -> [--json]");
+    process.exit(2);
+  }
+  const spec = JSON.parse(readSpecRaw(input).toString("utf8"));
   const { checks, errors, warnings } = validateSpec(spec);
-  const receipt = { schemaVersion: 1, ok: errors === 0, command: "validate", input: resolve(input), checks, composition: { profile: "showcase", status: errors === 0 ? "pass" : "fail", summary: { errors, warnings } } };
+  const receipt = { schemaVersion: 1, ok: errors === 0, command: "validate", input: specLabel(input), checks, composition: { profile: "showcase", status: errors === 0 ? "pass" : "fail", summary: { errors, warnings } } };
   if (jsonOut) console.log(JSON.stringify(receipt, null, 2));
   else console.log(errors === 0 ? `pass ${checks.length}/${checks.length}` : `fail ${errors} checks`);
   process.exit(errors === 0 ? 0 : 1);
 } else if (cmd === "deliver") {
   const [input, output] = args;
-  const inAbs = resolve(input), outAbs = resolve(output);
-  const raw = readFileSync(inAbs);
+  if (!input || !output) {
+    console.error("usage: trace.mjs deliver <spec.json | -> <out.html>");
+    process.exit(2);
+  }
+  const inAbs = specLabel(input), outAbs = resolve(output);
+  const raw = readSpecRaw(input);
   const spec = JSON.parse(raw.toString("utf8"));
   const { checks, errors, warnings } = validateSpec(spec);
   if (errors > 0) {
@@ -184,6 +202,6 @@ if (cmd === "doctor") {
   writeFileSync(resolve(dir, "loop-trace-demo.html"), renderHtml(spec, { checks }));
   console.log(`Demo ready: ${resolve(dir, "loop-trace-demo.html")}`);
 } else {
-  console.error("usage: trace.mjs [doctor|validate|deliver|demo] ...");
+  console.error('usage: trace.mjs [doctor|validate|deliver|demo] ...  (input "-" reads the spec from stdin)');
   process.exit(2);
 }
diff --git a/test/trace.test.mjs b/test/trace.test.mjs
index 6fda23e..49b8c1e 100644
--- a/test/trace.test.mjs
+++ b/test/trace.test.mjs
@@ -12,11 +12,12 @@ const ROOT = resolve(dirname(fileURLToPath(import.meta.url)), "..");
 const BIN = join(ROOT, "bin", "trace.mjs");
 const EXAMPLES = ["examples/strands-forcing.json", "examples/dspy-reward.json"];
 
-function run(args) {
+function run(args, opts = {}) {
   try {
     const stdout = execFileSync(process.execPath, [BIN, ...args], {
       encoding: "utf8",
       cwd: ROOT,
+      ...opts,
     });
     return { code: 0, stdout };
   } catch (error) {
@@ -24,6 +25,15 @@ function run(args) {
   }
 }
 
+test("validate reads a spec from stdin via '-'", () => {
+  const input = readFileSync(join(ROOT, EXAMPLES[0]), "utf8");
+  const r = run(["validate", "-", "--json"], { input });
+  assert.equal(r.code, 0);
+  const receipt = JSON.parse(r.stdout);
+  assert.equal(receipt.ok, true);
+  assert.equal(receipt.input, "<stdin>");
+});
+
 test("doctor reports a ready toolchain", () => {
   const r = run(["doctor", "--json"]);
   assert.equal(r.code, 0);