diff --git a/.gitignore b/.gitignore
index e27d1fa..d4129b3 100644
--- a/.gitignore
+++ b/.gitignore
@@ -53,3 +53,6 @@ logs/
 
 # Python scripts
 __pycache__/*
+
+# Node.js (compliance tests)
+tests/node_modules/
diff --git a/tests/bin/compliance-test.ts b/tests/bin/compliance-test.ts
new file mode 100644
index 0000000..520fde4
--- /dev/null
+++ b/tests/bin/compliance-test.ts
@@ -0,0 +1,270 @@
+import {
+  testTemplates,
+  runAllTests,
+  type TestConfig,
+  type TestResult,
+} from "../src/compliance-tests.ts";
+
+const colors = {
+  green: (s: string) => `\x1b[32m${s}\x1b[0m`,
+  red: (s: string) => `\x1b[31m${s}\x1b[0m`,
+  yellow: (s: string) => `\x1b[33m${s}\x1b[0m`,
+  gray: (s: string) => `\x1b[90m${s}\x1b[0m`,
+};
+
+interface CliArgs {
+  baseUrl?: string;
+  apiKey?: string;
+  model?: string;
+  authHeader?: string;
+  noBearer?: boolean;
+  noAuth?: boolean;
+  filter?: string[];
+  verbose?: boolean;
+  json?: boolean;
+  help?: boolean;
+}
+
+function parseArgs(argv: string[]): CliArgs {
+  const args: CliArgs = {};
+  let i = 0;
+
+  while (i < argv.length) {
+    const arg = argv[i];
+    const nextArg = argv[i + 1];
+
+    switch (arg) {
+      case "--base-url":
+      case "-u":
+        args.baseUrl = nextArg;
+        i += 2;
+        break;
+      case "--api-key":
+      case "-k":
+        args.apiKey = nextArg;
+        i += 2;
+        break;
+      case "--model":
+      case "-m":
+        args.model = nextArg;
+        i += 2;
+        break;
+      case "--auth-header":
+        args.authHeader = nextArg;
+        i += 2;
+        break;
+      case "--no-bearer":
+        args.noBearer = true;
+        i += 1;
+        break;
+      case "--no-auth":
+        args.noAuth = true;
+        i += 1;
+        break;
+      case "--filter":
+      case "-f":
+        args.filter = nextArg.split(",").map((s) => s.trim());
+        i += 2;
+        break;
+      case "--verbose":
+      case "-v":
+        args.verbose = true;
+        i += 1;
+        break;
+      case "--json":
+        args.json = true;
+        i += 1;
+        break;
+      case "--help":
+      case "-h":
+        args.help = true;
+        i += 1;
+        break;
+      default:
+        i += 1;
+    }
+  }
+
+  return args;
+}
+
+function printHelp() {
+  console.log(`
+Usage: npm run test:compliance -- [options]
+
+Options:
+  -u, --base-url <url>        Gateway base URL (default: http://localhost:8080)
+  -k, --api-key <key>         API key (or set OPENRESPONSES_API_KEY env var)
+      --no-auth               Skip authentication header entirely
+  -m, --model <model>         Model name (default: gpt-4o-mini)
+      --auth-header <name>    Auth header name (default: Authorization)
+      --no-bearer             Disable Bearer prefix in auth header
+  -f, --filter <ids>          Filter tests by ID (comma-separated)
+  -v, --verbose               Verbose output with request/response details
+      --json                  Output results as JSON
+  -h, --help                  Show this help message
+
+Test IDs:
+  ${testTemplates.map((t) => t.id).join(", ")}
+
+Examples:
+  npm run test:compliance
+  npm run test:compliance -- --model claude-3-5-sonnet-20241022
+  npm run test:compliance -- --filter basic-response,streaming-response
+  npm run test:compliance -- --verbose --filter basic-response
+  npm run test:compliance -- --json > results.json
+`);
+}
+
+function getStatusIcon(status: TestResult["status"]): string {
+  switch (status) {
+    case "passed":
+      return colors.green("✓");
+    case "failed":
+      return colors.red("✗");
+    case "running":
+      return colors.yellow("◉");
+    case "pending":
+      return colors.gray("○");
+  }
+}
+
+function printResult(result: TestResult, verbose: boolean) {
+  const icon = getStatusIcon(result.status);
+  const duration = result.duration ? ` (${result.duration}ms)` : "";
+  const events =
+    result.streamEvents !== undefined ? ` [${result.streamEvents} events]` : "";
+  const name =
+    result.status === "failed" ? colors.red(result.name) : result.name;
+
+  console.log(`${icon} ${name}${duration}${events}`);
+
+  if (result.status === "failed" && result.errors?.length) {
+    for (const error of result.errors) {
+      console.log(`  ${colors.red("✗")} ${error}`);
+    }
+
+    if (verbose) {
+      if (result.request) {
+        console.log(`\n  Request:`);
+        console.log(
+          `  ${JSON.stringify(result.request, null, 2).split("\n").join("\n  ")}`,
+        );
+      }
+      if (result.response) {
+        console.log(`\n  Response:`);
+        const responseStr =
+          typeof result.response === "string"
+            ? result.response
+            : JSON.stringify(result.response, null, 2);
+        console.log(`  ${responseStr.split("\n").join("\n  ")}`);
+      }
+    }
+  }
+}
+
+async function main() {
+  const args = parseArgs(process.argv.slice(2));
+
+  if (args.help) {
+    printHelp();
+    process.exit(0);
+  }
+
+  const baseUrl = args.baseUrl || "http://localhost:8080";
+  const apiKey = args.apiKey || process.env.OPENRESPONSES_API_KEY || "";
+
+  if (!apiKey && !args.noAuth) {
+    // No auth is fine for local gateway without auth enabled
+  }
+
+  const config: TestConfig = {
+    baseUrl,
+    apiKey,
+    model: args.model || "gpt-4o-mini",
+    authHeaderName: args.authHeader || "Authorization",
+    useBearerPrefix: !args.noBearer,
+  };
+
+  if (args.filter?.length) {
+    const availableIds = testTemplates.map((t) => t.id);
+    const invalidFilters = args.filter.filter(
+      (id) => !availableIds.includes(id),
+    );
+    if (invalidFilters.length) {
+      console.error(
+        `${colors.red("Error:")} Invalid test IDs: ${invalidFilters.join(", ")}`,
+      );
+      console.error(`Available test IDs: ${availableIds.join(", ")}`);
+      process.exit(1);
+    }
+  }
+
+  const allUpdates: TestResult[] = [];
+
+  const onProgress = (result: TestResult) => {
+    if (args.filter && !args.filter.includes(result.id)) {
+      return;
+    }
+    allUpdates.push(result);
+    if (!args.json && result.status !== "running") {
+      printResult(result, args.verbose || false);
+    }
+  };
+
+  if (!args.json) {
+    console.log(`Running compliance tests against: ${baseUrl}`);
+    console.log(`Model: ${config.model}`);
+    if (args.filter) {
+      console.log(`Filter: ${args.filter.join(", ")}`);
+    }
+    console.log();
+  }
+
+  await runAllTests(config, onProgress);
+
+  const finalResults = allUpdates.filter(
+    (r) => r.status === "passed" || r.status === "failed",
+  );
+  const passed = finalResults.filter((r) => r.status === "passed").length;
+  const failed = finalResults.filter((r) => r.status === "failed").length;
+
+  if (args.json) {
+    console.log(
+      JSON.stringify(
+        {
+          summary: { passed, failed, total: finalResults.length },
+          results: finalResults,
+        },
+        null,
+        2,
+      ),
+    );
+  } else {
+    console.log(`\n${"=".repeat(50)}`);
+    console.log(
+      `Results: ${colors.green(`${passed} passed`)}, ${colors.red(`${failed} failed`)}, ${finalResults.length} total`,
+    );
+
+    if (failed > 0) {
+      console.log(`\nFailed tests:`);
+      for (const r of finalResults) {
+        if (r.status === "failed") {
+          console.log(`\n${r.name}:`);
+          for (const e of r.errors || []) {
+            console.log(`  - ${e}`);
+          }
+        }
+      }
+    } else {
+      console.log(`\n${colors.green("✓ All tests passed!")}`);
+    }
+  }
+
+  process.exit(failed > 0 ? 1 : 0);
+}
+
+main().catch((error) => {
+  console.error(colors.red("Fatal error:"), error);
+  process.exit(1);
+});
diff --git a/tests/package-lock.json b/tests/package-lock.json
new file mode 100644
index 0000000..de009be
--- /dev/null
+++ b/tests/package-lock.json
@@ -0,0 +1,58 @@
+{
+  "name": "go-llm-gateway-compliance-tests",
+  "version": "1.0.0",
+  "lockfileVersion": 3,
+  "requires": true,
+  "packages": {
+    "": {
+      "name": "go-llm-gateway-compliance-tests",
+      "version": "1.0.0",
+      "devDependencies": {
+        "@types/node": "^22.0.0",
+        "typescript": "^5.7.0",
+        "zod": "^3.24.0"
+      }
+    },
+    "node_modules/@types/node": {
+      "version": "22.19.13",
+      "resolved": "https://registry.npmjs.org/@types/node/-/node-22.19.13.tgz",
+      "integrity": "sha512-akNQMv0wW5uyRpD2v2IEyRSZiR+BeGuoB6L310EgGObO44HSMNT8z1xzio28V8qOrgYaopIDNA18YgdXd+qTiw==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "undici-types": "~6.21.0"
+      }
+    },
+    "node_modules/typescript": {
+      "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",
+        "tsserver": "bin/tsserver"
+      },
+      "engines": {
+        "node": ">=14.17"
+      }
+    },
+    "node_modules/undici-types": {
+      "version": "6.21.0",
+      "resolved": "https://registry.npmjs.org/undici-types/-/undici-types-6.21.0.tgz",
+      "integrity": "sha512-iwDZqg0QAGrg9Rav5H4n0M64c3mkR59cJ6wQp+7C4nI0gsmExaedaYLNO44eT4AtBBwjbTiGPMlt2Md0T9H9JQ==",
+      "dev": true,
+      "license": "MIT"
+    },
+    "node_modules/zod": {
+      "version": "3.25.76",
+      "resolved": "https://registry.npmjs.org/zod/-/zod-3.25.76.tgz",
+      "integrity": "sha512-gzUt/qt81nXsFGKIFcC3YnfEAx5NkunCfnDlvuBSSFS02bcXu4Lmea0AFIUwbLWxWPx3d9p8S5QoaujKcNQxcQ==",
+      "dev": true,
+      "license": "MIT",
+      "funding": {
+        "url": "https://github.com/sponsors/colinhacks"
+      }
+    }
+  }
+}
diff --git a/tests/package.json b/tests/package.json
new file mode 100644
index 0000000..7a7670f
--- /dev/null
+++ b/tests/package.json
@@ -0,0 +1,17 @@
+{
+  "name": "go-llm-gateway-compliance-tests",
+  "version": "1.0.0",
+  "private": true,
+  "description": "Open Responses compliance tests for go-llm-gateway",
+  "type": "module",
+  "scripts": {
+    "test:compliance": "node --experimental-strip-types bin/compliance-test.ts",
+    "test:compliance:verbose": "node --experimental-strip-types bin/compliance-test.ts --verbose",
+    "test:compliance:json": "node --experimental-strip-types bin/compliance-test.ts --json"
+  },
+  "devDependencies": {
+    "zod": "^3.24.0",
+    "typescript": "^5.7.0",
+    "@types/node": "^22.0.0"
+  }
+}
diff --git a/tests/src/compliance-tests.ts b/tests/src/compliance-tests.ts
new file mode 100644
index 0000000..b76deeb
--- /dev/null
+++ b/tests/src/compliance-tests.ts
@@ -0,0 +1,370 @@
+import { responseResourceSchema, type ResponseResource } from "./schemas.ts";
+import { parseSSEStream, type SSEParseResult } from "./sse-parser.ts";
+
+export interface TestConfig {
+  baseUrl: string;
+  apiKey: string;
+  authHeaderName: string;
+  useBearerPrefix: boolean;
+  model: string;
+}
+
+export interface TestResult {
+  id: string;
+  name: string;
+  description: string;
+  status: "pending" | "running" | "passed" | "failed";
+  duration?: number;
+  request?: unknown;
+  response?: unknown;
+  errors?: string[];
+  streamEvents?: number;
+}
+
+interface ValidatorContext {
+  streaming: boolean;
+  sseResult?: SSEParseResult;
+}
+
+type ResponseValidator = (
+  response: ResponseResource,
+  context: ValidatorContext,
+) => string[];
+
+export interface TestTemplate {
+  id: string;
+  name: string;
+  description: string;
+  getRequest: (config: TestConfig) => Record<string, unknown>;
+  streaming?: boolean;
+  validators: ResponseValidator[];
+}
+
+// ============================================================
+// Validators
+// ============================================================
+
+const hasOutput: ResponseValidator = (response) => {
+  if (!response.output || response.output.length === 0) {
+    return ["Response has no output items"];
+  }
+  return [];
+};
+
+const hasOutputType =
+  (type: string): ResponseValidator =>
+  (response) => {
+    const hasType = response.output?.some((item) => item.type === type);
+    if (!hasType) {
+      return [`Expected output item of type "${type}" but none found`];
+    }
+    return [];
+  };
+
+const completedStatus: ResponseValidator = (response) => {
+  if (response.status !== "completed") {
+    return [`Expected status "completed" but got "${response.status}"`];
+  }
+  return [];
+};
+
+const streamingEvents: ResponseValidator = (_, context) => {
+  if (!context.streaming) return [];
+  if (!context.sseResult || context.sseResult.events.length === 0) {
+    return ["No streaming events received"];
+  }
+  return [];
+};
+
+const streamingSchema: ResponseValidator = (_, context) => {
+  if (!context.streaming || !context.sseResult) return [];
+  return context.sseResult.errors;
+};
+
+// ============================================================
+// Test Templates
+// ============================================================
+
+export const testTemplates: TestTemplate[] = [
+  {
+    id: "basic-response",
+    name: "Basic Text Response",
+    description: "Simple user message, validates ResponseResource schema",
+    getRequest: (config) => ({
+      model: config.model,
+      input: [
+        {
+          type: "message",
+          role: "user",
+          content: [{ type: "input_text", text: "Say hello in exactly 3 words." }],
+        },
+      ],
+    }),
+    validators: [hasOutput, completedStatus],
+  },
+
+  {
+    id: "streaming-response",
+    name: "Streaming Response",
+    description: "Validates SSE streaming events and final response",
+    streaming: true,
+    getRequest: (config) => ({
+      model: config.model,
+      input: [
+        {
+          type: "message",
+          role: "user",
+          content: [{ type: "input_text", text: "Count from 1 to 5." }],
+        },
+      ],
+    }),
+    validators: [streamingEvents, streamingSchema, completedStatus],
+  },
+
+  {
+    id: "system-prompt",
+    name: "System Prompt",
+    description: "Include system instructions via the instructions field",
+    getRequest: (config) => ({
+      model: config.model,
+      instructions: "You are a pirate. Always respond in pirate speak.",
+      input: [
+        {
+          type: "message",
+          role: "user",
+          content: [{ type: "input_text", text: "Say hello." }],
+        },
+      ],
+    }),
+    validators: [hasOutput, completedStatus],
+  },
+
+  {
+    id: "tool-calling",
+    name: "Tool Calling",
+    description: "Define a function tool and verify function_call output",
+    getRequest: (config) => ({
+      model: config.model,
+      input: [
+        {
+          type: "message",
+          role: "user",
+          content: [
+            {
+              type: "input_text",
+              text: "What's the weather like in San Francisco?",
+            },
+          ],
+        },
+      ],
+      tools: [
+        {
+          type: "function",
+          name: "get_weather",
+          description: "Get the current weather for a location",
+          parameters: {
+            type: "object",
+            properties: {
+              location: {
+                type: "string",
+                description: "The city and state, e.g. San Francisco, CA",
+              },
+            },
+            required: ["location"],
+          },
+        },
+      ],
+    }),
+    validators: [hasOutput, hasOutputType("function_call")],
+  },
+
+  {
+    id: "image-input",
+    name: "Image Input",
+    description: "Send image URL in user content",
+    getRequest: (config) => ({
+      model: config.model,
+      input: [
+        {
+          type: "message",
+          role: "user",
+          content: [
+            {
+              type: "input_text",
+              text: "What do you see in this image? Answer in one sentence.",
+            },
+            {
+              type: "input_image",
+              image_url:
+                "data:image/png;base64,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",
+            },
+          ],
+        },
+      ],
+    }),
+    validators: [hasOutput, completedStatus],
+  },
+
+  {
+    id: "multi-turn",
+    name: "Multi-turn Conversation",
+    description: "Send assistant + user messages as conversation history",
+    getRequest: (config) => ({
+      model: config.model,
+      input: [
+        {
+          type: "message",
+          role: "user",
+          content: [{ type: "input_text", text: "My name is Alice." }],
+        },
+        {
+          type: "message",
+          role: "assistant",
+          content: [
+            {
+              type: "output_text",
+              text: "Hello Alice! Nice to meet you. How can I help you today?",
+            },
+          ],
+        },
+        {
+          type: "message",
+          role: "user",
+          content: [{ type: "input_text", text: "What is my name?" }],
+        },
+      ],
+    }),
+    validators: [hasOutput, completedStatus],
+  },
+];
+
+// ============================================================
+// Test Runner
+// ============================================================
+
+async function makeRequest(
+  config: TestConfig,
+  body: Record<string, unknown>,
+  streaming = false,
+): Promise<Response> {
+  const headers: Record<string, string> = {
+    "Content-Type": "application/json",
+  };
+
+  if (config.apiKey) {
+    const authValue = config.useBearerPrefix
+      ? `Bearer ${config.apiKey}`
+      : config.apiKey;
+    headers[config.authHeaderName] = authValue;
+  }
+
+  return fetch(`${config.baseUrl}/v1/responses`, {
+    method: "POST",
+    headers,
+    body: JSON.stringify({ ...body, stream: streaming }),
+  });
+}
+
+async function runTest(
+  template: TestTemplate,
+  config: TestConfig,
+): Promise<TestResult> {
+  const startTime = Date.now();
+  const requestBody = template.getRequest(config);
+  const streaming = template.streaming ?? false;
+
+  try {
+    const response = await makeRequest(config, requestBody, streaming);
+    const duration = Date.now() - startTime;
+
+    if (!response.ok) {
+      const errorText = await response.text();
+      return {
+        id: template.id,
+        name: template.name,
+        description: template.description,
+        status: "failed",
+        duration,
+        request: requestBody,
+        response: errorText,
+        errors: [`HTTP ${response.status}: ${errorText}`],
+      };
+    }
+
+    let rawData: unknown;
+    let sseResult: SSEParseResult | undefined;
+
+    if (streaming) {
+      sseResult = await parseSSEStream(response);
+      rawData = sseResult.finalResponse;
+    } else {
+      rawData = await response.json();
+    }
+
+    // Schema validation with Zod
+    const parseResult = responseResourceSchema.safeParse(rawData);
+    if (!parseResult.success) {
+      return {
+        id: template.id,
+        name: template.name,
+        description: template.description,
+        status: "failed",
+        duration,
+        request: streaming ? { ...requestBody, stream: true } : requestBody,
+        response: rawData,
+        errors: parseResult.error.issues.map(
+          (issue) => `${issue.path.join(".")}: ${issue.message}`,
+        ),
+        streamEvents: sseResult?.events.length,
+      };
+    }
+
+    // Semantic validators
+    const context: ValidatorContext = { streaming, sseResult };
+    const errors = template.validators.flatMap((v) =>
+      v(parseResult.data, context),
+    );
+
+    return {
+      id: template.id,
+      name: template.name,
+      description: template.description,
+      status: errors.length === 0 ? "passed" : "failed",
+      duration,
+      request: streaming ? { ...requestBody, stream: true } : requestBody,
+      response: parseResult.data,
+      errors,
+      streamEvents: sseResult?.events.length,
+    };
+  } catch (error) {
+    return {
+      id: template.id,
+      name: template.name,
+      description: template.description,
+      status: "failed",
+      duration: Date.now() - startTime,
+      request: requestBody,
+      errors: [error instanceof Error ? error.message : String(error)],
+    };
+  }
+}
+
+export async function runAllTests(
+  config: TestConfig,
+  onProgress: (result: TestResult) => void,
+): Promise<TestResult[]> {
+  const promises = testTemplates.map(async (template) => {
+    onProgress({
+      id: template.id,
+      name: template.name,
+      description: template.description,
+      status: "running",
+    });
+
+    const result = await runTest(template, config);
+    onProgress(result);
+    return result;
+  });
+
+  return Promise.all(promises);
+}
diff --git a/tests/src/schemas.ts b/tests/src/schemas.ts
new file mode 100644
index 0000000..6f9ae5a
--- /dev/null
+++ b/tests/src/schemas.ts
@@ -0,0 +1,253 @@
+import { z } from "zod";
+
+// ============================================================
+// Content Parts
+// ============================================================
+
+const outputTextContentSchema = z.object({
+  type: z.literal("output_text"),
+  text: z.string(),
+  annotations: z.array(z.object({
+    type: z.string(),
+  })),
+});
+
+const inputTextContentSchema = z.object({
+  type: z.literal("input_text"),
+  text: z.string(),
+});
+
+const refusalContentSchema = z.object({
+  type: z.literal("refusal"),
+  refusal: z.string(),
+});
+
+const contentPartSchema = z.discriminatedUnion("type", [
+  outputTextContentSchema,
+  inputTextContentSchema,
+  refusalContentSchema,
+]);
+
+// ============================================================
+// Output Items
+// ============================================================
+
+const messageOutputItemSchema = z.object({
+  type: z.literal("message"),
+  id: z.string(),
+  status: z.enum(["in_progress", "completed", "incomplete"]),
+  role: z.enum(["user", "assistant", "system", "developer"]),
+  content: z.array(contentPartSchema),
+});
+
+const functionCallOutputItemSchema = z.object({
+  type: z.literal("function_call"),
+  id: z.string(),
+  call_id: z.string(),
+  name: z.string(),
+  arguments: z.string(),
+  status: z.enum(["in_progress", "completed", "incomplete"]),
+});
+
+const outputItemSchema = z.discriminatedUnion("type", [
+  messageOutputItemSchema,
+  functionCallOutputItemSchema,
+]);
+
+// ============================================================
+// Usage
+// ============================================================
+
+const usageSchema = z.object({
+  input_tokens: z.number().int(),
+  output_tokens: z.number().int(),
+  total_tokens: z.number().int(),
+  input_tokens_details: z.object({
+    cached_tokens: z.number().int(),
+  }),
+  output_tokens_details: z.object({
+    reasoning_tokens: z.number().int(),
+  }),
+});
+
+// ============================================================
+// ResponseResource
+// ============================================================
+
+export const responseResourceSchema = z.object({
+  id: z.string(),
+  object: z.literal("response"),
+  created_at: z.number().int(),
+  completed_at: z.number().int().nullable(),
+  status: z.string(),
+  incomplete_details: z.object({ reason: z.string() }).nullable(),
+  model: z.string(),
+  previous_response_id: z.string().nullable(),
+  instructions: z.string().nullable(),
+  output: z.array(outputItemSchema),
+  error: z.object({ type: z.string(), message: z.string() }).nullable(),
+  tools: z.any(),
+  tool_choice: z.any(),
+  truncation: z.string(),
+  parallel_tool_calls: z.boolean(),
+  text: z.any(),
+  top_p: z.number(),
+  presence_penalty: z.number(),
+  frequency_penalty: z.number(),
+  top_logprobs: z.number().int(),
+  temperature: z.number(),
+  reasoning: z.any().nullable(),
+  usage: usageSchema.nullable(),
+  max_output_tokens: z.number().int().nullable(),
+  max_tool_calls: z.number().int().nullable(),
+  store: z.boolean(),
+  background: z.boolean(),
+  service_tier: z.string(),
+  metadata: z.any(),
+  safety_identifier: z.string().nullable(),
+  prompt_cache_key: z.string().nullable(),
+});
+
+export type ResponseResource = z.infer<typeof responseResourceSchema>;
+
+// ============================================================
+// Streaming Event Schemas
+// ============================================================
+
+const responseCreatedEventSchema = z.object({
+  type: z.literal("response.created"),
+  sequence_number: z.number().int(),
+  response: responseResourceSchema,
+});
+
+const responseInProgressEventSchema = z.object({
+  type: z.literal("response.in_progress"),
+  sequence_number: z.number().int(),
+  response: responseResourceSchema,
+});
+
+const responseCompletedEventSchema = z.object({
+  type: z.literal("response.completed"),
+  sequence_number: z.number().int(),
+  response: responseResourceSchema,
+});
+
+const responseFailedEventSchema = z.object({
+  type: z.literal("response.failed"),
+  sequence_number: z.number().int(),
+  response: responseResourceSchema,
+});
+
+const outputItemAddedEventSchema = z.object({
+  type: z.literal("response.output_item.added"),
+  sequence_number: z.number().int(),
+  output_index: z.number().int(),
+  item: z.object({
+    id: z.string(),
+    type: z.string(),
+    status: z.string(),
+    role: z.string().optional(),
+    content: z.array(z.any()).optional(),
+  }),
+});
+
+const outputItemDoneEventSchema = z.object({
+  type: z.literal("response.output_item.done"),
+  sequence_number: z.number().int(),
+  output_index: z.number().int(),
+  item: z.object({
+    id: z.string(),
+    type: z.string(),
+    status: z.string(),
+    role: z.string().optional(),
+    content: z.array(z.any()).optional(),
+  }),
+});
+
+const contentPartAddedEventSchema = z.object({
+  type: z.literal("response.content_part.added"),
+  sequence_number: z.number().int(),
+  item_id: z.string(),
+  output_index: z.number().int(),
+  content_index: z.number().int(),
+  part: z.object({
+    type: z.string(),
+    text: z.string().optional(),
+    annotations: z.array(z.any()).optional(),
+  }),
+});
+
+const contentPartDoneEventSchema = z.object({
+  type: z.literal("response.content_part.done"),
+  sequence_number: z.number().int(),
+  item_id: z.string(),
+  output_index: z.number().int(),
+  content_index: z.number().int(),
+  part: z.object({
+    type: z.string(),
+    text: z.string().optional(),
+    annotations: z.array(z.any()).optional(),
+  }),
+});
+
+const outputTextDeltaEventSchema = z.object({
+  type: z.literal("response.output_text.delta"),
+  sequence_number: z.number().int(),
+  item_id: z.string(),
+  output_index: z.number().int(),
+  content_index: z.number().int(),
+  delta: z.string(),
+});
+
+const outputTextDoneEventSchema = z.object({
+  type: z.literal("response.output_text.done"),
+  sequence_number: z.number().int(),
+  item_id: z.string(),
+  output_index: z.number().int(),
+  content_index: z.number().int(),
+  text: z.string(),
+});
+
+const functionCallArgsDeltaEventSchema = z.object({
+  type: z.literal("response.function_call_arguments.delta"),
+  sequence_number: z.number().int(),
+  item_id: z.string(),
+  output_index: z.number().int(),
+  delta: z.string(),
+});
+
+const functionCallArgsDoneEventSchema = z.object({
+  type: z.literal("response.function_call_arguments.done"),
+  sequence_number: z.number().int(),
+  item_id: z.string(),
+  output_index: z.number().int(),
+  arguments: z.string(),
+});
+
+const errorEventSchema = z.object({
+  type: z.literal("error"),
+  sequence_number: z.number().int(),
+  error: z.object({
+    type: z.string(),
+    message: z.string(),
+    code: z.string().nullable().optional(),
+  }),
+});
+
+export const streamingEventSchema = z.discriminatedUnion("type", [
+  responseCreatedEventSchema,
+  responseInProgressEventSchema,
+  responseCompletedEventSchema,
+  responseFailedEventSchema,
+  outputItemAddedEventSchema,
+  outputItemDoneEventSchema,
+  contentPartAddedEventSchema,
+  contentPartDoneEventSchema,
+  outputTextDeltaEventSchema,
+  outputTextDoneEventSchema,
+  functionCallArgsDeltaEventSchema,
+  functionCallArgsDoneEventSchema,
+  errorEventSchema,
+]);
+
+export type StreamingEvent = z.infer<typeof streamingEventSchema>;
diff --git a/tests/src/sse-parser.ts b/tests/src/sse-parser.ts
new file mode 100644
index 0000000..222b542
--- /dev/null
+++ b/tests/src/sse-parser.ts
@@ -0,0 +1,92 @@
+import type { z } from "zod";
+import {
+  streamingEventSchema,
+  type StreamingEvent,
+  type ResponseResource,
+} from "./schemas.ts";
+
+export interface ParsedEvent {
+  event: string;
+  data: unknown;
+  validationResult: z.SafeParseReturnType<unknown, StreamingEvent>;
+}
+
+export interface SSEParseResult {
+  events: ParsedEvent[];
+  errors: string[];
+  finalResponse: ResponseResource | null;
+}
+
+export async function parseSSEStream(
+  response: Response,
+): Promise<SSEParseResult> {
+  const events: ParsedEvent[] = [];
+  const errors: string[] = [];
+  let finalResponse: ResponseResource | null = null;
+
+  const reader = response.body?.getReader();
+  if (!reader) {
+    return { events, errors: ["No response body"], finalResponse };
+  }
+
+  const decoder = new TextDecoder();
+  let buffer = "";
+
+  try {
+    while (true) {
+      const { done, value } = await reader.read();
+      if (done) break;
+
+      buffer += decoder.decode(value, { stream: true });
+      const lines = buffer.split("\n");
+      buffer = lines.pop() || "";
+
+      let currentEvent = "";
+      let currentData = "";
+
+      for (const line of lines) {
+        if (line.startsWith("event:")) {
+          currentEvent = line.slice(6).trim();
+        } else if (line.startsWith("data:")) {
+          currentData = line.slice(5).trim();
+        } else if (line === "" && currentData) {
+          if (currentData === "[DONE]") {
+            // Skip sentinel
+          } else {
+            try {
+              const parsed = JSON.parse(currentData);
+              const validationResult = streamingEventSchema.safeParse(parsed);
+
+              events.push({
+                event: currentEvent || parsed.type || "unknown",
+                data: parsed,
+                validationResult,
+              });
+
+              if (!validationResult.success) {
+                errors.push(
+                  `Event validation failed for ${parsed.type || "unknown"}: ${JSON.stringify(validationResult.error.issues)}`,
+                );
+              }
+
+              if (
+                parsed.type === "response.completed" ||
+                parsed.type === "response.failed"
+              ) {
+                finalResponse = parsed.response;
+              }
+            } catch {
+              errors.push(`Failed to parse event data: ${currentData}`);
+            }
+          }
+          currentEvent = "";
+          currentData = "";
+        }
+      }
+    }
+  } finally {
+    reader.releaseLock();
+  }
+
+  return { events, errors, finalResponse };
+}
diff --git a/tests/tsconfig.json b/tests/tsconfig.json
new file mode 100644
index 0000000..d055c5c
--- /dev/null
+++ b/tests/tsconfig.json
@@ -0,0 +1,14 @@
+{
+  "compilerOptions": {
+    "target": "ES2022",
+    "module": "NodeNext",
+    "moduleResolution": "NodeNext",
+    "strict": true,
+    "esModuleInterop": true,
+    "skipLibCheck": true,
+    "outDir": "dist",
+    "rootDir": ".",
+    "declaration": true
+  },
+  "include": ["src/**/*.ts", "bin/**/*.ts"]
+}