diff --git a/moli-cdp-smoke/moli_cdp_smoke/puppeteer_aria_queries.mjs b/moli-cdp-smoke/moli_cdp_smoke/puppeteer_aria_queries.mjs
new file mode 100644
index 0000000000..45bc6cc4b7
--- /dev/null
+++ b/moli-cdp-smoke/moli_cdp_smoke/puppeteer_aria_queries.mjs
@@ -0,0 +1,97 @@
+export async function runPuppeteerAriaQuerySmoke(page) {
+  await page.evaluate(async () => {
+    document.body.innerHTML = `
+      <main id="aria-root"><button id="aria-go">Go</button></main>
+      <button id="aria-stay">Stay</button>
+    `;
+    globalThis.__puppeteerAriaClicks = 0;
+    document.querySelector('#aria-go').addEventListener('click', () => {
+      globalThis.__puppeteerAriaClicks += 1;
+    });
+    const iframe = document.createElement('iframe');
+    iframe.id = 'aria-frame';
+    iframe.srcdoc = '<button id="aria-child">Child Go</button>';
+    await new Promise(resolve => {
+      iframe.addEventListener('load', resolve, { once: true });
+      document.body.append(iframe);
+    });
+  });
+
+  for (const selector of ['aria/Go', 'aria/Go[role="button"]']) {
+    const handle = await page.$(selector);
+    if (!handle) {
+      throw new Error(`Puppeteer ARIA selector did not match: ${selector}`);
+    }
+    try {
+      const id = await handle.evaluate(element => element.id);
+      if (id !== 'aria-go') {
+        throw new Error(`Puppeteer ARIA selector returned ${id}: ${selector}`);
+      }
+    } finally {
+      await handle.dispose();
+    }
+  }
+
+  const buttons = await page.$$('aria/[role="button"]');
+  try {
+    const ids = (await Promise.all(buttons.map(handle => handle.evaluate(element => element.id)))).sort();
+    if (JSON.stringify(ids) !== JSON.stringify(['aria-go', 'aria-stay'])) {
+      throw new Error(`Puppeteer ARIA role query returned unexpected elements: ${JSON.stringify(ids)}`);
+    }
+  } finally {
+    await Promise.all(buttons.map(handle => handle.dispose()));
+  }
+
+  if (await page.$('aria/Missing')) {
+    throw new Error('Puppeteer ARIA query must return null for a missing name');
+  }
+
+  const root = await page.$('#aria-root');
+  if (!root) {
+    throw new Error('Puppeteer ARIA query fixture root is missing');
+  }
+  try {
+    if (await root.$('aria/Stay')) {
+      throw new Error('Puppeteer ARIA query escaped its element subtree');
+    }
+    const go = await root.waitForSelector('aria/Go[role="button"]', { timeout: 3000 });
+    if (!go) {
+      throw new Error('Puppeteer scoped ARIA wait returned no element');
+    }
+    try {
+      await go.evaluate(element => element.click());
+    } finally {
+      await go.dispose();
+    }
+  } finally {
+    await root.dispose();
+  }
+  const clicks = await page.evaluate(() => globalThis.__puppeteerAriaClicks);
+  if (clicks !== 1) {
+    throw new Error(`Puppeteer ARIA handle must activate the matched element once: ${clicks}`);
+  }
+
+  const iframe = await page.$('#aria-frame');
+  if (!iframe) {
+    throw new Error('Puppeteer ARIA query fixture iframe is missing');
+  }
+  try {
+    const frame = await iframe.contentFrame();
+    const child = await frame?.$('aria/Child Go[role="button"]');
+    if (!child) {
+      throw new Error('Puppeteer ARIA selector did not match in the child frame');
+    }
+    try {
+      const id = await child.evaluate(element => element.id);
+      if (id !== 'aria-child') {
+        throw new Error(`Puppeteer child-frame ARIA selector returned ${id}`);
+      }
+    } finally {
+      await child.dispose();
+    }
+  } finally {
+    await iframe.dispose();
+  }
+
+  return { selectors: ['name', 'name-and-role', 'role', 'missing', 'scoped-wait', 'iframe'] };
+}
diff --git a/moli-cdp-smoke/moli_cdp_smoke/puppeteer_smoke.mjs b/moli-cdp-smoke/moli_cdp_smoke/puppeteer_smoke.mjs
index 7f11b24993..bfcbea3304 100644
--- a/moli-cdp-smoke/moli_cdp_smoke/puppeteer_smoke.mjs
+++ b/moli-cdp-smoke/moli_cdp_smoke/puppeteer_smoke.mjs
@@ -4,6 +4,7 @@ import { createRequire } from 'node:module';
 import os from 'node:os';
 import path from 'node:path';
 
+import { runPuppeteerAriaQuerySmoke } from './puppeteer_aria_queries.mjs';
 import {
   activateXPathElement,
   runPuppeteerDomInteractionSmoke,
@@ -437,6 +438,12 @@ async function main() {
     }
     record('puppeteer_evaluate_fetch');
 
+    const ariaQueryResult = await withTimeout(
+      'Puppeteer ARIA selectors',
+      runPuppeteerAriaQuerySmoke(page),
+    );
+    record('puppeteer_aria_selector_workflow', ariaQueryResult);
+
     const domInteractionResult = await withTimeout(
       'Puppeteer DOM interaction matrix',
       runPuppeteerDomInteractionSmoke(page),
diff --git a/moli-protocol/src/domains/accessibility.rs b/moli-protocol/src/domains/accessibility.rs
index e9cae6c689..2876dbf0b0 100644
--- a/moli-protocol/src/domains/accessibility.rs
+++ b/moli-protocol/src/domains/accessibility.rs
@@ -40,7 +40,7 @@ enum PendingAccessibilityCommandKind {
     },
     ChildFrameRoot,
     ObjectAccessibilityPayloads {
-        frame_id: String,
+        frame_id: Option<String>,
         top_frame_id: String,
         operation: AccessibilityNodeOperation,
     },
@@ -412,28 +412,25 @@ fn start_pending_object_reference_command(
     let Some(top_frame_id) = helpers::top_frame_id_for_session(conn, cmd.session_id) else {
         return Err(PendingAccessibilityCommandStartError::no_document_loaded());
     };
-    let resolved_frame_id = frame_id.unwrap_or(top_frame_id.as_str()).to_owned();
     let Some(object_id) = reference.object_id.as_deref() else {
         return Err(PendingAccessibilityCommandStartError {
             code: -32000,
             message: "Could not find node with given id".to_owned(),
         });
     };
+    let inspector_session_id =
+        conn.target_renderer_runtime_inspector_session_id_for_session(cmd.session_id);
     let Some(page) = helpers::loaded_page_mut_for_session(conn, cmd.session_id) else {
         return Err(PendingAccessibilityCommandStartError::no_document_loaded());
     };
-    let pending = start_accessibility_object_page_command(
-        page,
-        cmd.session_id.map(str::to_owned),
-        object_id,
-        &operation,
-    )
-    .map_err(PendingAccessibilityCommandStartError::renderer_error)?;
+    let pending =
+        start_accessibility_object_page_command(page, inspector_session_id, object_id, &operation)
+            .map_err(PendingAccessibilityCommandStartError::renderer_error)?;
     Ok(Some(PendingAccessibilityCommandDispatch::from_command(
         conn,
         cmd,
         PendingAccessibilityCommandKind::ObjectAccessibilityPayloads {
-            frame_id: resolved_frame_id,
+            frame_id: frame_id.map(str::to_owned),
             top_frame_id,
             operation,
         },
@@ -720,7 +717,7 @@ pub(crate) async fn complete_pending_accessibility_command(
 fn complete_object_accessibility_payloads_command(
     page: &mut moli_core::page::Page,
     completion: CompletedPageCommand,
-    frame_id: String,
+    frame_id: Option<String>,
     top_frame_id: String,
     operation: AccessibilityNodeOperation,
 ) -> CommandOutputPlan {
@@ -740,7 +737,11 @@ fn complete_object_accessibility_payloads_command(
         .frame_id
         .as_deref()
         .unwrap_or(top_frame_id.as_str());
-    if object_frame_id != frame_id {
+    // Object IDs identify their own frame unless the caller explicitly constrains it.
+    if frame_id
+        .as_deref()
+        .is_some_and(|frame_id| object_frame_id != frame_id)
+    {
         return CommandOutputPlan::error(-32000, "Could not find node with given id");
     }
     let Some(mut nodes) = payloads.payloads else {
diff --git a/moli-protocol/src/domains/accessibility/native.rs b/moli-protocol/src/domains/accessibility/native.rs
index 0bf45c8c21..7c0d2b2e91 100644
--- a/moli-protocol/src/domains/accessibility/native.rs
+++ b/moli-protocol/src/domains/accessibility/native.rs
@@ -197,9 +197,8 @@ fn reference_operation(
     top_frame_id: String,
     operation: AccessibilityNodeOperation,
 ) -> Result<Operation, StartError> {
-    let frame_id = frame_id.unwrap_or_else(|| top_frame_id.clone());
     if let Some(object_id) = reference.object_id {
-        let session = cmd.session_id.map(str::to_owned);
+        let session = conn.target_renderer_runtime_inspector_session_id_for_session(cmd.session_id);
         let command = match &operation {
             AccessibilityNodeOperation::Ancestors => {
                 Command::accessibility_node_and_ancestor_payloads_for_object_id(session, object_id)
@@ -220,6 +219,7 @@ fn reference_operation(
             project_nodes(reply, frame_id, top_frame_id, operation)
         }));
     }
+    let frame_id = frame_id.unwrap_or_else(|| top_frame_id.clone());
     let reference = if let Some(id) = renderer_backend_node_id_for_reference(&reference) {
         DevToolsDomNodeReference::BackendNodeId(id)
     } else {
@@ -261,13 +261,13 @@ fn node_operation(
         }
     };
     Operation::new(command, move |reply| {
-        project_nodes(reply, frame_id, top_frame_id, operation)
+        project_nodes(reply, Some(frame_id), top_frame_id, operation)
     })
 }
 
 fn project_nodes(
     reply: anyhow::Result<Reply>,
-    frame_id: String,
+    frame_id: Option<String>,
     top_frame_id: String,
     operation: AccessibilityNodeOperation,
 ) -> Response {
@@ -282,7 +282,11 @@ fn project_nodes(
         }
         _ => unreachable!("accessibility node reply"),
     };
-    if payload.frame_id.as_deref().unwrap_or(&top_frame_id) != frame_id {
+    // Object IDs identify their own frame unless the caller explicitly constrains it.
+    if frame_id
+        .as_deref()
+        .is_some_and(|frame_id| payload.frame_id.as_deref().unwrap_or(&top_frame_id) != frame_id)
+    {
         return node_not_found();
     }
     let Some(mut nodes) = payload.payloads else {
diff --git a/moli-protocol/src/domains/accessibility/tests.rs b/moli-protocol/src/domains/accessibility/tests.rs
index 647f20c252..a3b9af97b8 100644
--- a/moli-protocol/src/domains/accessibility/tests.rs
+++ b/moli-protocol/src/domains/accessibility/tests.rs
@@ -2517,6 +2517,131 @@ async fn query_ax_tree_supports_object_id_and_empty_match() {
     assert_eq!(empty["result"]["nodes"], json!([]));
 }
 
+#[tokio::test(flavor = "multi_thread")]
+async fn query_ax_tree_object_id_uses_owning_inspector_session() {
+    let mut ctx = TestContext::new();
+    load_page_async(
+        &mut ctx,
+        "<!doctype html><html><body><button id='go'>Go</button></body></html>",
+    )
+    .await;
+    let browser_context = ctx.conn.browser_context.as_mut().expect("browser context");
+    browser_context.attach_active_session("SID-primary");
+    assert!(browser_context.assign_attached_session_to_target("TID-1", "SID-attached".to_owned()));
+
+    for (session_id, other_session_id) in [
+        ("SID-primary", "SID-attached"),
+        ("SID-attached", "SID-primary"),
+    ] {
+        ctx.process_async(json!({
+            "id": 560,
+            "method": "Runtime.enable",
+            "sessionId": session_id
+        }))
+        .await;
+        ctx.take_all();
+        ctx.process_async(json!({
+            "id": 561,
+            "method": "Page.createIsolatedWorld",
+            "sessionId": session_id,
+            "params": { "frameId": "TID-1", "worldName": format!("ax-query-{session_id}") }
+        }))
+        .await;
+        let context_id = ctx.take_response_by_id(561)["result"]["executionContextId"]
+            .as_i64()
+            .expect("isolated world id");
+        ctx.take_all();
+        ctx.process_async(json!({
+            "id": 562,
+            "method": "Runtime.evaluate",
+            "sessionId": session_id,
+            "params": { "expression": "document", "contextId": context_id }
+        }))
+        .await;
+        let object_id = ctx.take_response_by_id(562)["result"]["result"]["objectId"]
+            .as_str()
+            .expect("document object id")
+            .to_owned();
+
+        ctx.process_async(json!({
+            "id": 563,
+            "method": "Accessibility.queryAXTree",
+            "sessionId": session_id,
+            "params": { "objectId": object_id, "role": "button", "accessibleName": "Go" }
+        }))
+        .await;
+        let message = ctx.take_response_by_id(563);
+        let nodes = message["result"]["nodes"]
+            .as_array()
+            .unwrap_or_else(|| panic!("{session_id} AX query failed: {message}"));
+        assert_eq!(nodes.len(), 1);
+        assert_eq!(nodes[0]["role"]["value"], "button");
+        assert_eq!(nodes[0]["name"]["value"], "Go");
+
+        ctx.process_async(json!({
+            "id": 564,
+            "method": "Accessibility.queryAXTree",
+            "sessionId": other_session_id,
+            "params": { "objectId": object_id, "role": "button" }
+        }))
+        .await;
+        ctx.expect_error(564, -32000, "Could not find node with given id");
+    }
+}
+
+#[tokio::test(flavor = "multi_thread")]
+async fn query_ax_tree_object_id_infers_child_frame_and_checks_explicit_frame() {
+    let mut ctx = TestContext::new();
+    load_page_async(
+        &mut ctx,
+        "<!doctype html><html><body><button>Parent</button><iframe srcdoc=\"<button>Go</button>\"></iframe></body></html>",
+    )
+    .await;
+    enable_runtime_async(&mut ctx).await;
+    let child_frame_id = child_frame_id_for_single_iframe_async(&mut ctx).await;
+    ctx.process_async(json!({
+        "id": 565,
+        "method": "Page.createIsolatedWorld",
+        "params": { "frameId": child_frame_id, "worldName": "ax-query-child-document" }
+    }))
+    .await;
+    let context_id = ctx.take_response_by_id(565)["result"]["executionContextId"]
+        .as_i64()
+        .expect("child isolated world id");
+    ctx.take_all();
+    ctx.process_async(json!({
+        "id": 566,
+        "method": "Runtime.evaluate",
+        "params": { "expression": "document", "contextId": context_id }
+    }))
+    .await;
+    let object_id = ctx.take_response_by_id(566)["result"]["result"]["objectId"]
+        .as_str()
+        .expect("child document object id")
+        .to_owned();
+
+    ctx.process_async(json!({
+        "id": 567,
+        "method": "Accessibility.queryAXTree",
+        "params": { "objectId": object_id, "role": "button" }
+    }))
+    .await;
+    let message = ctx.take_response_by_id(567);
+    let nodes = message["result"]["nodes"]
+        .as_array()
+        .unwrap_or_else(|| panic!("child AX query failed: {message}"));
+    assert_eq!(nodes.len(), 1);
+    assert_eq!(nodes[0]["name"]["value"], "Go");
+
+    ctx.process_async(json!({
+        "id": 568,
+        "method": "Accessibility.queryAXTree",
+        "params": { "objectId": object_id, "frameId": "TID-1", "role": "button" }
+    }))
+    .await;
+    ctx.expect_error(568, -32000, "Could not find node with given id");
+}
+
 #[tokio::test(flavor = "multi_thread")]
 async fn query_ax_tree_requires_context_loaded_page_and_bound_node() {
     let mut ctx = TestContext::new();