From 9c3a4facebd52bfd3c16126108cf43306f0cd4da Mon Sep 17 00:00:00 2001
From: nipunrajk <nipunraj99@gmail.com>
Date: Fri, 26 Jun 2026 15:19:34 +0530
Subject: [PATCH] feat(cdp): signal when the ref list is truncated in look()

---
 packages/cdp/src/actions.ts       | 8 ++++++--
 packages/cdp/src/snapshot.test.ts | 6 ++++--
 packages/cdp/src/snapshot.ts      | 7 +++++--
 3 files changed, 15 insertions(+), 6 deletions(-)

diff --git a/packages/cdp/src/actions.ts b/packages/cdp/src/actions.ts
index 5c17348..eb84c6c 100644
--- a/packages/cdp/src/actions.ts
+++ b/packages/cdp/src/actions.ts
@@ -62,7 +62,7 @@ export async function look(ctx: BrowserContext, opts: LookOptions = {}): Promise
 
   // a11y (default)
   const tree = await ctx.session.send<{ nodes: AXNode[] }>("Accessibility.getFullAXTree", {});
-  const { refs, refMap, truncated } = compactAxTree(tree.nodes ?? []);
+  const { refs, refMap, truncated, truncatedCount } = compactAxTree(tree.nodes ?? []);
 
   ctx.lastRefs.clear();
   for (const [k, v] of refMap) ctx.lastRefs.set(k, v);
@@ -74,7 +74,11 @@ export async function look(ctx: BrowserContext, opts: LookOptions = {}): Promise
     filtered = refs.filter((r) => r.role.toLowerCase().includes(f) || r.name.toLowerCase().includes(f));
   }
   const header = `${title}\n${url}\n${filtered.length} of ${refs.length} refs${truncated ? " (TRUNCATED at 200)" : ""}`;
-  return { snapshot, text: `${header}\n${renderRefs(filtered)}` };
+  let text = `${header}\n${renderRefs(filtered)}`;
+  if (truncated && truncatedCount > 0) {
+    text += `\n… ${truncatedCount} more elements below — scroll or filter`;
+  }
+  return { snapshot, text };
 }
 
 function delta(snapshot: Snapshot, summary: string): SnapshotDelta {
diff --git a/packages/cdp/src/snapshot.test.ts b/packages/cdp/src/snapshot.test.ts
index 9a4ff28..9d47054 100644
--- a/packages/cdp/src/snapshot.test.ts
+++ b/packages/cdp/src/snapshot.test.ts
@@ -56,12 +56,13 @@ const tree: AXNode[] = [
 ];
 
 describe("compactAxTree", () => {
-  const { refs, refMap, truncated } = compactAxTree(tree);
+  const { refs, refMap, truncated, truncatedCount } = compactAxTree(tree);
 
   it("keeps only interactive + named-role nodes that are not ignored and have a backend id", () => {
     expect(refs.map((r) => r.role)).toEqual(["button", "textbox", "checkbox", "heading"]);
     expect(refs.map((r) => r.name)).toEqual(["Sign in", "Email", "Remember me", "Welcome"]);
     expect(truncated).toBe(false);
+    expect(truncatedCount).toBe(0);
   });
 
   it("assigns sequential ref ids from 1", () => {
@@ -117,8 +118,9 @@ describe("compactAxTree truncation", () => {
         backendDOMNodeId: i + 1,
       }),
     );
-    const { refs, truncated } = compactAxTree(many);
+    const { refs, truncated, truncatedCount } = compactAxTree(many);
     expect(refs.length).toBe(200);
     expect(truncated).toBe(true);
+    expect(truncatedCount).toBe(50);
   });
 });
diff --git a/packages/cdp/src/snapshot.ts b/packages/cdp/src/snapshot.ts
index 373f29a..78ed7bc 100644
--- a/packages/cdp/src/snapshot.ts
+++ b/packages/cdp/src/snapshot.ts
@@ -88,6 +88,7 @@ export interface CompactionResult {
   /** ref id -> resolution info needed by act/fill. */
   refMap: Map<number, { backendDOMNodeId: number; role: string; name: string }>;
   truncated: boolean;
+  truncatedCount: number;
 }
 
 /**
@@ -100,6 +101,7 @@ export function compactAxTree(nodes: AXNode[]): CompactionResult {
   const refMap = new Map<number, { backendDOMNodeId: number; role: string; name: string }>();
   let counter = 0;
   let truncated = false;
+  let truncatedCount = 0;
 
   for (const node of nodes) {
     if (node.ignored) continue;
@@ -115,7 +117,8 @@ export function compactAxTree(nodes: AXNode[]): CompactionResult {
 
     if (refs.length >= MAX_REFS) {
       truncated = true;
-      break;
+      truncatedCount++;
+      continue;
     }
 
     const ref = ++counter;
@@ -124,7 +127,7 @@ export function compactAxTree(nodes: AXNode[]): CompactionResult {
     refMap.set(ref, { backendDOMNodeId: node.backendDOMNodeId, role, name });
   }
 
-  return { refs, refMap, truncated };
+  return { refs, refMap, truncated, truncatedCount };
 }
 
 /** Render refs as compact "[ref] role \"name\" (state)" lines. */