diff --git a/packages/ai/src/auth/oauth/aimlapi.ts b/packages/ai/src/auth/oauth/aimlapi.ts
new file mode 100644
index 00000000000..3a97838de12
--- /dev/null
+++ b/packages/ai/src/auth/oauth/aimlapi.ts
@@ -0,0 +1,161 @@
+/**
+ * AI/ML API passwordless email sign-in.
+ *
+ * Unlike OpenRouter's PKCE browser-redirect flow, AI/ML API's login is a
+ * terminal-native email + one-time-code exchange (no browser or loopback
+ * server involved): resolve whether the email signs in or signs up, collect
+ * a verification code (existing accounts only), exchange it for a session
+ * token, then mint a permanent API key scoped to this login. The result is
+ * wrapped as an "oauth" credential the same way OpenRouter's key exchange
+ * is — a permanent key, not an expiring access/refresh pair.
+ */
+
+import type { OAuthAuth, OAuthCredential, ProviderAuthInteraction } from "../types.ts";
+
+const AUTH_BASE_URL = "https://auth.aimlapi.com";
+const APP_BASE_URL = "https://app.aimlapi.com";
+const REQUEST_TIMEOUT_MS = 30_000;
+const KEY_NAME = "pi CLI";
+
+type JsonObject = Record<string, unknown>;
+
+function isRecord(value: unknown): value is JsonObject {
+	return typeof value === "object" && value !== null;
+}
+
+function errorDetail(body: JsonObject): string | undefined {
+	if (typeof body.message === "string") return body.message;
+	if (typeof body.error === "string") return body.error;
+	return undefined;
+}
+
+async function request(
+	method: "GET" | "POST" | "PATCH",
+	url: string,
+	options: { body?: unknown; bearer?: string; expectJson?: boolean; signal: AbortSignal },
+): Promise<JsonObject | undefined> {
+	const controller = new AbortController();
+	const onAbort = () => controller.abort(options.signal.reason);
+	options.signal.addEventListener("abort", onAbort, { once: true });
+	const timeout = setTimeout(
+		() => controller.abort(new Error(`AI/ML API request to ${url} timed out`)),
+		REQUEST_TIMEOUT_MS,
+	);
+
+	let response: Response;
+	try {
+		response = await fetch(url, {
+			method,
+			headers: {
+				accept: "application/json",
+				...(options.body !== undefined ? { "content-type": "application/json" } : {}),
+				...(options.bearer ? { authorization: `Bearer ${options.bearer}` } : {}),
+			},
+			...(options.body !== undefined ? { body: JSON.stringify(options.body) } : {}),
+			signal: controller.signal,
+		});
+	} catch (error) {
+		if (options.signal.aborted) throw new Error("Login cancelled");
+		if (controller.signal.aborted) throw new Error(`AI/ML API request to ${url} timed out`);
+		throw error;
+	} finally {
+		clearTimeout(timeout);
+		options.signal.removeEventListener("abort", onAbort);
+	}
+
+	if (options.expectJson === false) {
+		if (!response.ok) throw new Error(`AI/ML API request failed (HTTP ${response.status})`);
+		return undefined;
+	}
+
+	let body: JsonObject = {};
+	try {
+		const parsed = (await response.json()) as unknown;
+		if (isRecord(parsed)) body = parsed;
+	} catch {
+		if (response.ok) throw new Error("AI/ML API returned invalid JSON");
+	}
+
+	if (!response.ok) {
+		const detail = errorDetail(body);
+		throw new Error(`AI/ML API request failed (HTTP ${response.status})${detail ? `: ${detail}` : ""}`);
+	}
+	return body;
+}
+
+async function checkAccount(
+	email: string,
+	signal: AbortSignal,
+): Promise<{ action: "sign-in" | "sign-up"; provider?: string }> {
+	const body = await request("PATCH", `${AUTH_BASE_URL}/v1/auth/account`, { body: { email }, signal });
+	const action = body?.action;
+	if (action !== "sign-in" && action !== "sign-up") throw new Error("AI/ML API returned an invalid account response");
+	return { action, provider: typeof body?.provider === "string" ? body.provider : undefined };
+}
+
+async function sendSignInCode(email: string, signal: AbortSignal): Promise<void> {
+	await request("POST", `${AUTH_BASE_URL}/v1/auth/sign-in/code`, { body: { email }, expectJson: false, signal });
+}
+
+async function exchangeForToken(path: string, body: JsonObject, signal: AbortSignal): Promise<string> {
+	const result = await request("POST", `${AUTH_BASE_URL}${path}`, { body, signal });
+	const token = result?.token;
+	if (typeof token !== "string" || token.length === 0) throw new Error("AI/ML API did not return an auth token");
+	return token;
+}
+
+async function createKey(bearer: string, signal: AbortSignal): Promise<string> {
+	const result = await request("POST", `${APP_BASE_URL}/v1/keys`, { body: { name: KEY_NAME }, bearer, signal });
+	const key = result?.key;
+	if (typeof key !== "string" || key.length === 0) throw new Error("AI/ML API did not return an API key");
+	return key;
+}
+
+async function loginAimlapi(interaction: ProviderAuthInteraction): Promise<OAuthCredential> {
+	const rawEmail = await interaction.prompt({ type: "text", message: "Enter your AI/ML API account email" });
+	const email = rawEmail.trim();
+	if (!email) throw new Error("Email is required");
+
+	interaction.notify({ type: "progress", message: "Checking your AI/ML API account..." });
+	const account = await checkAccount(email, interaction.signal);
+
+	let sessionToken: string;
+	if (account.action === "sign-up") {
+		interaction.notify({ type: "progress", message: "Creating your AI/ML API account..." });
+		sessionToken = await exchangeForToken("/v1/auth/account/passwordless", { email }, interaction.signal);
+	} else {
+		if (account.provider) {
+			throw new Error(
+				`This email signs in via ${account.provider} on AI/ML API — sign in at https://aimlapi.com/app and create an API key manually instead.`,
+			);
+		}
+		await sendSignInCode(email, interaction.signal);
+		interaction.notify({ type: "info", message: `A 6-digit code was sent to ${email}.` });
+		const rawCode = await interaction.prompt({ type: "text", message: "Enter the 6-digit code" });
+		const code = rawCode.trim();
+		if (!code) throw new Error("Code is required");
+		sessionToken = await exchangeForToken("/v1/auth/sign-in/code/verify", { email, code }, interaction.signal);
+	}
+
+	interaction.notify({ type: "progress", message: "Creating an AI/ML API key for pi..." });
+	const key = await createKey(sessionToken, interaction.signal);
+
+	return {
+		type: "oauth",
+		access: key,
+		refresh: "",
+		expires: Number.MAX_SAFE_INTEGER,
+	};
+}
+
+export const aimlapiOAuth: OAuthAuth = {
+	name: "AI/ML API sign-in",
+	loginLabel: "Sign in with AI/ML API",
+	login: loginAimlapi,
+	async refresh(credential, _signal) {
+		return credential;
+	},
+	async toAuth(credential) {
+		return { apiKey: credential.access };
+	},
+};
diff --git a/packages/ai/src/auth/oauth/load.ts b/packages/ai/src/auth/oauth/load.ts
index e9c72d87d67..46e6061f153 100644
--- a/packages/ai/src/auth/oauth/load.ts
+++ b/packages/ai/src/auth/oauth/load.ts
@@ -12,6 +12,7 @@ const importOAuthModule = (specifier: string): Promise<unknown> => {
 };
 
 type OAuthFlowLoaders = {
+	aimlapi: () => OAuthAuth | Promise<OAuthAuth>;
 	anthropic: () => OAuthAuth | Promise<OAuthAuth>;
 	openaiCodex: () => OAuthAuth | Promise<OAuthAuth>;
 	githubCopilot: () => OAuthAuth | Promise<OAuthAuth>;
@@ -28,6 +29,11 @@ export function registerBundledOAuthFlowLoaders(loaders: OAuthFlowLoaders): void
 	bundledLoaders = loaders;
 }
 
+export const loadAimlapiOAuth = async (): Promise<OAuthAuth> => {
+	if (bundledLoaders) return bundledLoaders.aimlapi();
+	return ((await importOAuthModule("./aimlapi.ts")) as { aimlapiOAuth: OAuthAuth }).aimlapiOAuth;
+};
+
 export const loadAnthropicOAuth = async (): Promise<OAuthAuth> => {
 	if (bundledLoaders) return bundledLoaders.anthropic();
 	return ((await importOAuthModule("./anthropic.ts")) as { anthropicOAuth: OAuthAuth }).anthropicOAuth;
diff --git a/packages/ai/src/bun-oauth.ts b/packages/ai/src/bun-oauth.ts
index d1370214df1..2dc677b1360 100644
--- a/packages/ai/src/bun-oauth.ts
+++ b/packages/ai/src/bun-oauth.ts
@@ -1,3 +1,4 @@
+import { aimlapiOAuth } from "./auth/oauth/aimlapi.ts";
 import { anthropicOAuth } from "./auth/oauth/anthropic.ts";
 import { githubCopilotOAuth } from "./auth/oauth/github-copilot.ts";
 import { kimiCodingOAuth } from "./auth/oauth/kimi-coding.ts";
@@ -10,6 +11,7 @@ import { xaiOAuth } from "./auth/oauth/xai.ts";
 /** Register OAuth flows statically embedded in the standalone Bun binary. */
 export function registerBunOAuthFlows(): void {
 	registerBundledOAuthFlowLoaders({
+		aimlapi: () => aimlapiOAuth,
 		anthropic: () => anthropicOAuth,
 		openaiCodex: () => openaiCodexOAuth,
 		githubCopilot: () => githubCopilotOAuth,
diff --git a/packages/ai/src/providers/aimlapi.ts b/packages/ai/src/providers/aimlapi.ts
index d283ffac575..ad461cb8e32 100644
--- a/packages/ai/src/providers/aimlapi.ts
+++ b/packages/ai/src/providers/aimlapi.ts
@@ -1,5 +1,6 @@
 import { openAICompletionsApi } from "../api/openai-completions.lazy.ts";
-import { envApiKeyAuth } from "../auth/helpers.ts";
+import { envApiKeyAuth, lazyOAuth } from "../auth/helpers.ts";
+import { loadAimlapiOAuth } from "../auth/oauth/load.ts";
 import { createProvider, type Provider } from "../models.ts";
 import { AIMLAPI_MODELS } from "./aimlapi.models.ts";
 
@@ -10,6 +11,11 @@ export function aimlapiProvider(): Provider<"openai-completions"> {
 		baseUrl: "https://api.aimlapi.com/v1",
 		auth: {
 			apiKey: envApiKeyAuth("AI/ML API key", ["AIMLAPI_API_KEY"]),
+			oauth: lazyOAuth({
+				name: "AI/ML API sign-in",
+				loginLabel: "Sign in with AI/ML API",
+				load: loadAimlapiOAuth,
+			}),
 		},
 		models: Object.values(AIMLAPI_MODELS),
 		api: openAICompletionsApi(),
diff --git a/packages/ai/test/aimlapi-oauth.test.ts b/packages/ai/test/aimlapi-oauth.test.ts
new file mode 100644
index 00000000000..3bc0eb4e48a
--- /dev/null
+++ b/packages/ai/test/aimlapi-oauth.test.ts
@@ -0,0 +1,173 @@
+import { afterEach, describe, expect, it, vi } from "vitest";
+import { aimlapiOAuth } from "../src/auth/oauth/aimlapi.ts";
+import { aimlapiProvider } from "../src/providers/aimlapi.ts";
+
+const ACCOUNT_URL = "https://auth.aimlapi.com/v1/auth/account";
+const SEND_CODE_URL = "https://auth.aimlapi.com/v1/auth/sign-in/code";
+const VERIFY_CODE_URL = "https://auth.aimlapi.com/v1/auth/sign-in/code/verify";
+const PASSWORDLESS_URL = "https://auth.aimlapi.com/v1/auth/account/passwordless";
+const KEYS_URL = "https://app.aimlapi.com/v1/keys";
+const neverAbortedSignal = new AbortController().signal;
+
+function jsonResponse(body: unknown, status = 200): Response {
+	return new Response(JSON.stringify(body), { status, headers: { "content-type": "application/json" } });
+}
+
+function requestBody(init: RequestInit | undefined): Record<string, unknown> {
+	return JSON.parse(String(init?.body)) as Record<string, unknown>;
+}
+
+describe.sequential("AI/ML API OAuth", () => {
+	afterEach(() => {
+		vi.unstubAllGlobals();
+	});
+
+	it("is exposed alongside API-key auth", () => {
+		const provider = aimlapiProvider();
+		expect(provider.auth.apiKey).toBeDefined();
+		expect(provider.auth.oauth).toBeDefined();
+		expect(provider.auth.oauth?.loginLabel).toBe("Sign in with AI/ML API");
+	});
+
+	it("signs in an existing account with an emailed code and mints an API key", async () => {
+		const calls: string[] = [];
+		let verifyBody: Record<string, unknown> | undefined;
+		let keyBody: Record<string, unknown> | undefined;
+		let keyAuthHeader: string | null | undefined;
+		vi.stubGlobal(
+			"fetch",
+			vi.fn(async (input: string | URL | Request, init?: RequestInit) => {
+				const url = input instanceof Request ? input.url : String(input);
+				calls.push(url);
+				if (url === ACCOUNT_URL) return jsonResponse({ action: "sign-in" });
+				if (url === SEND_CODE_URL) return new Response(null, { status: 204 });
+				if (url === VERIFY_CODE_URL) {
+					verifyBody = requestBody(init);
+					return jsonResponse({ token: "session-token", exp: 9999999999 });
+				}
+				if (url === KEYS_URL) {
+					keyBody = requestBody(init);
+					keyAuthHeader = new Headers(init?.headers).get("authorization");
+					return jsonResponse({ key: "aiml-test-key", id: "key-1" });
+				}
+				throw new Error(`Unexpected request: ${url}`);
+			}),
+		);
+
+		const prompts = ["user@example.com", "123456"];
+		const credential = await aimlapiOAuth.login({
+			signal: neverAbortedSignal,
+			prompt: async () => prompts.shift() ?? "",
+			notify: () => {},
+		});
+
+		expect(credential).toEqual({
+			type: "oauth",
+			access: "aiml-test-key",
+			refresh: "",
+			expires: Number.MAX_SAFE_INTEGER,
+		});
+		expect(calls).toEqual([ACCOUNT_URL, SEND_CODE_URL, VERIFY_CODE_URL, KEYS_URL]);
+		expect(verifyBody).toEqual({ email: "user@example.com", code: "123456" });
+		expect(keyBody).toEqual({ name: "pi CLI" });
+		expect(keyAuthHeader).toBe("Bearer session-token");
+	});
+
+	it("creates a new account without requesting a code when the account does not exist", async () => {
+		const calls: string[] = [];
+		vi.stubGlobal(
+			"fetch",
+			vi.fn(async (input: string | URL | Request) => {
+				const url = input instanceof Request ? input.url : String(input);
+				calls.push(url);
+				if (url === ACCOUNT_URL) return jsonResponse({ action: "sign-up" });
+				if (url === PASSWORDLESS_URL) return jsonResponse({ token: "new-session-token", exp: 9999999999 });
+				if (url === KEYS_URL) return jsonResponse({ key: "aiml-new-key", id: "key-2" });
+				throw new Error(`Unexpected request: ${url}`);
+			}),
+		);
+
+		const credential = await aimlapiOAuth.login({
+			signal: neverAbortedSignal,
+			prompt: async () => "new-user@example.com",
+			notify: () => {},
+		});
+
+		expect(credential).toMatchObject({ access: "aiml-new-key" });
+		expect(calls).toEqual([ACCOUNT_URL, PASSWORDLESS_URL, KEYS_URL]);
+	});
+
+	it("rejects an account linked to a third-party sign-in provider", async () => {
+		vi.stubGlobal(
+			"fetch",
+			vi.fn(async () => jsonResponse({ action: "sign-in", provider: "google" })),
+		);
+
+		await expect(
+			aimlapiOAuth.login({
+				signal: neverAbortedSignal,
+				prompt: async () => "user@example.com",
+				notify: () => {},
+			}),
+		).rejects.toThrow(/signs in via google/);
+	});
+
+	it("reports an invalid verification code", async () => {
+		vi.stubGlobal(
+			"fetch",
+			vi.fn(async (input: string | URL | Request) => {
+				const url = input instanceof Request ? input.url : String(input);
+				if (url === ACCOUNT_URL) return jsonResponse({ action: "sign-in" });
+				if (url === SEND_CODE_URL) return new Response(null, { status: 204 });
+				if (url === VERIFY_CODE_URL) return jsonResponse({ message: "invalid code" }, 400);
+				throw new Error(`Unexpected request: ${url}`);
+			}),
+		);
+
+		const prompts = ["user@example.com", "000000"];
+		await expect(
+			aimlapiOAuth.login({
+				signal: neverAbortedSignal,
+				prompt: async () => prompts.shift() ?? "",
+				notify: () => {},
+			}),
+		).rejects.toThrow("AI/ML API request failed (HTTP 400): invalid code");
+	});
+
+	it("rejects a successful key response that carries no key", async () => {
+		vi.stubGlobal(
+			"fetch",
+			vi.fn(async (input: string | URL | Request) => {
+				const url = input instanceof Request ? input.url : String(input);
+				if (url === ACCOUNT_URL) return jsonResponse({ action: "sign-in" });
+				if (url === SEND_CODE_URL) return new Response(null, { status: 204 });
+				if (url === VERIFY_CODE_URL) return jsonResponse({ token: "session-token", exp: 9999999999 });
+				if (url === KEYS_URL) return jsonResponse({ id: "key-1" });
+				throw new Error(`Unexpected request: ${url}`);
+			}),
+		);
+
+		const prompts = ["user@example.com", "123456"];
+		await expect(
+			aimlapiOAuth.login({
+				signal: neverAbortedSignal,
+				prompt: async () => prompts.shift() ?? "",
+				notify: () => {},
+			}),
+		).rejects.toThrow("AI/ML API did not return an API key");
+	});
+
+	it("rejects an empty email without making a request", async () => {
+		const fetchMock = vi.fn();
+		vi.stubGlobal("fetch", fetchMock);
+
+		await expect(
+			aimlapiOAuth.login({
+				signal: neverAbortedSignal,
+				prompt: async () => "   ",
+				notify: () => {},
+			}),
+		).rejects.toThrow("Email is required");
+		expect(fetchMock).not.toHaveBeenCalled();
+	});
+});