diff --git a/packages/sdk/package-lock.json b/packages/sdk/package-lock.json
index cbdf3606..af504a01 100644
--- a/packages/sdk/package-lock.json
+++ b/packages/sdk/package-lock.json
@@ -20,6 +20,8 @@
         "ajv-draft-04": "^1.0.0",
         "js-yaml": "^5.4.1",
         "re2js": "^2.8.6",
+        "typescript": "^5.6.0",
+        "undici": "^7.29.1",
         "yaml": "^2.5.1"
       },
       "bin": {
@@ -28,7 +30,6 @@
       "devDependencies": {
         "@agent-relay/cli-surface": "^12.2.4",
         "@types/node": "^22.7.0",
-        "typescript": "^5.6.0",
         "vitest": "^2.1.0"
       },
       "peerDependencies": {
@@ -3172,7 +3173,6 @@
       "version": "5.9.3",
       "resolved": "https://registry.npmjs.org/typescript/-/typescript-5.9.3.tgz",
       "integrity": "sha512-jl1vZzPDinLr9eUt3J/t7V6FgNEw9QjvBPdysz9KfQDD41fQrC2Y4vKQdiaUpFT4bXlb1RHhLpp8wtm6M5TgSw==",
-      "dev": true,
       "license": "Apache-2.0",
       "bin": {
         "tsc": "bin/tsc",
diff --git a/packages/sdk/package.json b/packages/sdk/package.json
index 24d7a13e..21811ec5 100644
--- a/packages/sdk/package.json
+++ b/packages/sdk/package.json
@@ -57,12 +57,13 @@
     "ajv-draft-04": "^1.0.0",
     "js-yaml": "^5.4.1",
     "re2js": "^2.8.6",
+    "typescript": "^5.6.0",
+    "undici": "^7.29.1",
     "yaml": "^2.5.1"
   },
   "devDependencies": {
     "@agent-relay/cli-surface": "^12.2.4",
     "@types/node": "^22.7.0",
-    "typescript": "^5.6.0",
     "vitest": "^2.1.0"
   },
   "repository": {
diff --git a/packages/sdk/tests/cli-package-gate.test.ts b/packages/sdk/tests/cli-package-gate.test.ts
new file mode 100644
index 00000000..53bac3a8
--- /dev/null
+++ b/packages/sdk/tests/cli-package-gate.test.ts
@@ -0,0 +1,13 @@
+import { execFileSync } from 'node:child_process';
+import { fileURLToPath } from 'node:url';
+import { it } from 'vitest';
+
+const skip = process.env.FLOWS_SKIP_PACKAGE_GATE === '1';
+if (skip) console.error('FLOWS_SKIP_PACKAGE_GATE=1: skipping network-dependent packed CLI installation test; packaging is unverified.');
+it.skipIf(skip)('checks authored flows with locally and globally installed release tarballs', () => {
+  execFileSync(process.execPath, ['scripts/cli-package-gate.mjs'], {
+    cwd: fileURLToPath(new URL('../../..', import.meta.url)),
+    stdio: 'inherit',
+    timeout: 115_000,
+  });
+}, 120_000);
diff --git a/packages/sdk/tests/runtime-dependencies.test.ts b/packages/sdk/tests/runtime-dependencies.test.ts
new file mode 100644
index 00000000..db7120ee
--- /dev/null
+++ b/packages/sdk/tests/runtime-dependencies.test.ts
@@ -0,0 +1,55 @@
+import { builtinModules } from 'node:module';
+import { readFileSync, readdirSync } from 'node:fs';
+import { join } from 'node:path';
+import { fileURLToPath } from 'node:url';
+import { parse, type Node, type AnyNode } from 'acorn';
+import { expect, it } from 'vitest';
+
+const sdk = fileURLToPath(new URL('..', import.meta.url));
+const builtins = new Set(builtinModules);
+
+it('declares every literal runtime import in the built SDK', () => {
+  const manifest = JSON.parse(readFileSync(join(sdk, 'package.json'), 'utf8'));
+  const declared = new Set(Object.keys({
+    ...manifest.dependencies, ...manifest.optionalDependencies, ...manifest.peerDependencies,
+  }));
+  const missing = new Set<string>();
+  let files = 0;
+  function specifier(value: unknown) {
+    if (typeof value !== 'string' || /^(\.|\/|node:)/.test(value) || builtins.has(value)) return;
+    const name = value.startsWith('@') ? value.split('/').slice(0, 2).join('/') : value.split('/')[0]!;
+    if (!declared.has(name)) missing.add(name);
+  }
+  // Computed imports/require calls cannot be checked by a literal AST scan.
+  function walk(node: Node) {
+    const n = node as AnyNode;
+    if (n.type === 'ImportDeclaration' || n.type === 'ExportNamedDeclaration' ||
+      n.type === 'ExportAllDeclaration' || n.type === 'ImportExpression') {
+      if (n.source?.type === 'Literal') specifier(n.source.value);
+    }
+    if (n.type === 'CallExpression' && (
+      (n.callee.type === 'Identifier' && n.callee.name === 'require') ||
+      (n.callee.type === 'MemberExpression' && !n.callee.computed &&
+        n.callee.object.type === 'Identifier' && n.callee.object.name === 'require' &&
+        n.callee.property.type === 'Identifier' && n.callee.property.name === 'resolve'))) {
+      if (n.arguments[0]?.type === 'Literal') specifier(n.arguments[0].value);
+    }
+    for (const value of Object.values(n)) {
+      if (Array.isArray(value)) value.forEach(child => { if (child?.type) walk(child); });
+      else if (value && typeof value === 'object' && 'type' in value) walk(value as Node);
+    }
+  }
+  function scan(directory: string) {
+    for (const entry of readdirSync(directory, { withFileTypes: true })) {
+      const path = join(directory, entry.name);
+      if (entry.isDirectory()) scan(path);
+      else if (entry.name.endsWith('.js')) {
+        files++;
+        walk(parse(readFileSync(path, 'utf8'), { ecmaVersion: 'latest', sourceType: 'module' }));
+      }
+    }
+  }
+  scan(join(sdk, 'dist'));
+  expect(files, 'Build the SDK before checking runtime dependencies').toBeGreaterThan(0);
+  expect([...missing].sort(), 'Undeclared runtime dependencies').toEqual([]);
+});
diff --git a/packages/sdk/tsconfig.tests.json b/packages/sdk/tsconfig.tests.json
index 04045eaa..773c991c 100644
--- a/packages/sdk/tsconfig.tests.json
+++ b/packages/sdk/tsconfig.tests.json
@@ -12,6 +12,8 @@
   "include": [
     "src/**/*.ts",
     "tests/isolate-workspace.ts",
+    "tests/runtime-dependencies.test.ts",
+    "tests/cli-package-gate.test.ts",
     "tests/run-projection.test.ts",
     "tests/observer-link.test.ts",
     "tests/bundle.test.ts",
diff --git a/scripts/cli-package-gate.mjs b/scripts/cli-package-gate.mjs
new file mode 100644
index 00000000..dd645cf1
--- /dev/null
+++ b/scripts/cli-package-gate.mjs
@@ -0,0 +1,98 @@
+#!/usr/bin/env node
+// Requires built surface + SDK. Install real release tarballs outside the repo.
+import assert from 'node:assert/strict';
+import { execFileSync } from 'node:child_process';
+import { existsSync, mkdirSync, mkdtempSync, readFileSync, readdirSync, realpathSync, rmSync, writeFileSync } from 'node:fs';
+import { createRequire } from 'node:module';
+import { tmpdir } from 'node:os';
+import { dirname, join, resolve, sep } from 'node:path';
+import { fileURLToPath } from 'node:url';
+
+const [major, minor] = process.versions.node.split('.').map(Number);
+assert(major > 22 || (major === 22 && minor >= 18),
+  'CLI packaging gate requires Node >=22.18.0 for .flow.ts type stripping; the published engines range is broader than this authored-flow requirement.');
+const root = resolve(dirname(fileURLToPath(import.meta.url)), '..');
+const require = createRequire(join(root, 'packages/sdk/package.json'));
+const ts = require('typescript');
+const fixture = 'dependency-upgrade-bot.flow.ts';
+const source = readFileSync(join(root, 'examples/dependency-upgrade-bot', fixture), 'utf8');
+const imports = new Set();
+function visit(node) {
+  if (ts.isImportDeclaration(node) || ts.isExportDeclaration(node)) {
+    if (node.moduleSpecifier) imports.add(node.moduleSpecifier.text);
+  }
+  if (ts.isCallExpression(node) && (node.expression.kind === ts.SyntaxKind.ImportKeyword ||
+    node.expression.getText() === 'require')) imports.add(node.arguments[0]?.text);
+  ts.forEachChild(node, visit);
+}
+visit(ts.createSourceFile(fixture, source, ts.ScriptTarget.Latest, true));
+assert.deepEqual([...imports], ['@relayflows/surface'],
+  'Packaging fixture must import only @relayflows/surface; consider task-graph, social-post-pipeline, pr-review-pipeline, or software-factory.');
+const temporary = realpathSync(mkdtempSync(join(tmpdir(), 'flows-cli-package-')));
+const env = { ...process.env };
+for (const key of ['NODE_PATH', 'NODE_OPTIONS', 'GITHUB_OUTPUT']) delete env[key];
+function run(command, args, cwd = root) {
+  console.log(`$ ${command} ${args.join(' ')}`);
+  try {
+    const output = execFileSync(command, args, { cwd, env, encoding: 'utf8', timeout: 60_000, stdio: ['ignore', 'pipe', 'pipe'] });
+    process.stdout.write(output);
+    return output;
+  } catch (error) {
+    process.stdout.write(error.stdout ?? '');
+    process.stderr.write(error.stderr ?? '');
+    throw error;
+  }
+}
+function project(name) {
+  const directory = join(temporary, name);
+  mkdirSync(join(directory, 'examples'), { recursive: true });
+  writeFileSync(join(directory, 'package.json'), '{"private":true,"type":"module"}\n');
+  writeFileSync(join(directory, 'examples', fixture), source);
+  return directory;
+}
+function check(binary, directory, args = []) {
+  const output = run(binary, [...args, 'check', `examples/${fixture}`], directory);
+  assert.match(output, /CHECK PASSED/);
+}
+function resolvedInside(manifest, boundary) {
+  const resolved = realpathSync(createRequire(manifest).resolve('typescript'));
+  assert(resolved.startsWith(`${boundary}${sep}`), `TypeScript resolved outside install: ${resolved}`);
+}
+try {
+  // Reject contaminated temp roots as well as temp directories inside the repo.
+  assert(!temporary.startsWith(`${root}${sep}`), 'Temp directory must be outside the repository');
+  for (let parent = dirname(temporary); ; parent = dirname(parent)) {
+    assert(!existsSync(join(parent, 'node_modules')), `Ancestor node_modules contaminates packaging test: ${parent}`);
+    if (parent === dirname(parent)) break;
+  }
+  const tarballs = join(temporary, 'tarballs');
+  for (const name of ['surface', 'sdk', 'relayflows']) {
+    run(process.execPath, ['scripts/pack-release.mjs', name, tarballs]);
+  }
+  const archives = readdirSync(tarballs).filter(name => name.endsWith('.tgz')).map(name => join(tarballs, name));
+  assert.equal(archives.length, 3);
+  // Optional platform binaries are unrelated to Node dependency resolution.
+  const flags = ['--ignore-scripts', '--omit=optional', '--no-audit', '--no-fund'];
+  const local = project('local');
+  run('npm', ['install', ...flags, ...archives], local);
+  check(join(local, 'node_modules/.bin/flows'), local);
+  check(process.execPath, local, [join(local, 'node_modules/relayflows/bin/flows.js')]);
+  resolvedInside(join(local, 'node_modules/@relayflows/sdk/package.json'), local);
+
+  const prefix = join(temporary, 'prefix');
+  run('npm', ['install', '-g', '--prefix', prefix, ...flags, ...archives], temporary);
+  assert.deepEqual(readdirSync(join(prefix, 'bin')).sort(), ['flows'], 'Global install must not expose tsc or tsserver');
+  // Both SDK and wrapper own a flows bin; also exercise the wrapper explicitly.
+  const wrapper = join(prefix, 'lib/node_modules/relayflows');
+  const globalProject = project('global-project');
+  const surface = archives.find(path => path.endsWith(`/relayflows-surface-${require('./package.json').version}.tgz`));
+  assert(surface, 'Missing surface archive');
+  run('npm', ['install', ...flags, surface], globalProject);
+  assert(!existsSync(join(globalProject, 'node_modules/typescript')), 'Global consumer must not supply TypeScript');
+  check(join(prefix, 'bin/flows'), globalProject);
+  check(process.execPath, globalProject, [join(wrapper, 'bin/flows.js')]);
+  resolvedInside(join(prefix, 'lib/node_modules/@relayflows/sdk/package.json'), prefix);
+  console.log('CLI_PACKAGE_OK: local and global installs');
+} finally {
+  rmSync(temporary, { recursive: true, force: true });
+}