diff --git a/src/browserNodeProvider.ts b/src/browserNodeProvider.ts
index 01081f4..8ef5b54 100644
--- a/src/browserNodeProvider.ts
+++ b/src/browserNodeProvider.ts
@@ -20,6 +20,7 @@
 import { maskTunnelUrl } from "./iicpConsumer.js";
 import type { ChatMessage } from "./iicpConsumer.js";
 import { createCxKeyPair, decryptPayload } from "./cxConfidentiality.js";
+import type { EffectiveCapability } from "./effectiveCapability.js";
 import {
   BROWSER_NODE_SDK_COMPATIBILITY_VERSION,
   BROWSER_NODE_SDK_VERSION,
@@ -42,6 +43,9 @@ export interface BrowserProviderConfig {
   directoryUrl?: string;
   /** Model name advertised to the directory (the loaded WebLLM model id). */
   model: string;
+  /** Complete service-path variants. When present, these replace the legacy
+   * text-only browser advertisement without merging fields across variants. */
+  effectiveCapabilities?: EffectiveCapability[];
   region?: string;
   onLog?: (line: string) => void;
   /** Called after each served task with the running total. */
@@ -74,6 +78,23 @@ export interface BrowserProviderDiagnostic {
 const CHAT_INTENT = "urn:iicp:intent:llm:chat:v1";
 export { BROWSER_NODE_SDK_VERSION } from "./version.js";
 
+/** Resolve the exact variants sent to the directory. Explicit effective
+ * capabilities take precedence; the historical browser default is preserved
+ * for callers that do not opt in. */
+export function advertisedBrowserCapabilities(
+  explicit: readonly EffectiveCapability[],
+  model: string,
+): EffectiveCapability[] {
+  return explicit.length > 0
+    ? explicit.map((capability) => ({ ...capability }))
+    : [{
+        intent: CHAT_INTENT,
+        models: [model],
+        max_tokens: 1024,
+        input_modalities: ["text"],
+      }];
+}
+
 /**
  * Coarse region autodetect from the browser's timezone (no network, no
  * geolocation permission). Matches the mesh's region convention
@@ -355,14 +376,10 @@ export class BrowserNodeProvider {
           node_id: this.nodeId,
           endpoint,
           region: this.cfg.region ?? detectRegion(),
-          capabilities: [
-            {
-              intent: CHAT_INTENT,
-              models: [this.cfg.model],
-              max_tokens: 1024,
-              input_modalities: ["text"],
-            },
-          ],
+          capabilities: advertisedBrowserCapabilities(
+            this.cfg.effectiveCapabilities ?? [],
+            this.cfg.model,
+          ),
           limits: { max_concurrent: 1, tokens_per_min: 6000 },
           transport_method: "turn_relay",
           exposure_mode: "relay_required",
diff --git a/tests/provider.test.ts b/tests/provider.test.ts
index b036ac3..c240660 100644
--- a/tests/provider.test.ts
+++ b/tests/provider.test.ts
@@ -9,6 +9,7 @@ import {
   BROWSER_NODE_SDK_VERSION,
   BROWSER_NODE_VERSION,
   discoverRelay,
+  advertisedBrowserCapabilities,
   encryptPayload,
   type BrowserProviderRuntime,
 } from "../src/index.ts";
@@ -34,6 +35,20 @@ function runtime(reply = "ok"): BrowserProviderRuntime {
   };
 }
 
+test("explicit effective variants replace the legacy browser advertisement", () => {
+  const explicit = [{
+    intent: "urn:iicp:intent:llm:chat:v1",
+    variant_id: "browser-vision",
+    models: ["custom-browser-model"],
+    input_modalities: ["text", "image"],
+    claim_provenance: { source: "runtime_introspection" as const },
+  }];
+  assert.deepEqual(
+    advertisedBrowserCapabilities(explicit, "legacy-browser-model"),
+    explicit,
+  );
+});
+
 test("discoverRelay requests a short-lived ticket and uses its relay route", async () => {
   let url = "";
   let requestBody: Record<string, unknown> | null = null;
@@ -119,6 +134,48 @@ test("start registers browser provider with CX key, relay exposure and current b
   assert.deepEqual(order.slice(0, 3), ["register", "ticket", "bind"]);
 });
 
+test("start sends configured effective capability variants to the directory", async () => {
+  let registerBody: Record<string, any> | null = null;
+  const effectiveCapabilities = [{
+    intent: "urn:iicp:intent:llm:chat:v1",
+    variant_id: "browser-vision",
+    models: ["custom-browser-model"],
+    input_modalities: ["text", "image"],
+    output_modalities: ["text"],
+    claim_provenance: { source: "runtime_introspection" as const },
+  }];
+  await withFetch(async (input, init) => {
+    const url = String(input);
+    if (url.endsWith("/v1/register") && init?.method === "POST") {
+      registerBody = JSON.parse(String(init.body));
+      return new Response(JSON.stringify({ node_token: "node-token" }));
+    }
+    if (url.endsWith("/v1/relay/ticket")) {
+      return new Response(JSON.stringify({ ticket: "signed-bind-ticket" }), { status: 201 });
+    }
+    if (url.endsWith("/v1/relay/bind")) {
+      return new Response(JSON.stringify({ session_token: "relay-session" }));
+    }
+    if (url.endsWith("/v1/heartbeat")) return new Response(JSON.stringify({ ok: true }));
+    if (url.endsWith("/v1/relay/pull")) return new Promise<Response>(() => undefined);
+    if (url.endsWith("/v1/relay/unbind") || (url.endsWith("/v1/register") && init?.method === "DELETE")) {
+      return new Response(JSON.stringify({ ok: true }));
+    }
+    throw new Error(`unexpected fetch ${url}`);
+  }, async () => {
+    const provider = new BrowserNodeProvider(runtime(), {
+      relayUrl: "https://relay.example",
+      relayNodeId: "relay-1",
+      directoryUrl: "https://directory.test/api",
+      model: "legacy-browser-model",
+      effectiveCapabilities,
+    });
+    await provider.start();
+    await provider.stop();
+  });
+  assert.deepEqual(registerBody?.capabilities, effectiveCapabilities);
+});
+
 test("provider exposes deterministic recovery state transitions", async () => {
   const diagnostics: string[] = [];
   await withFetch(async (input, init) => {