diff --git a/src/atlas.ts b/src/atlas.ts
index 36a0042..1871ca9 100644
--- a/src/atlas.ts
+++ b/src/atlas.ts
@@ -65,7 +65,7 @@ export interface AtlasChatResult {
 // Main chat handler
 // ---------------------------------------------------------------------------
 
-const ATLAS_TOOLS = ALL_TOOLS.filter(t => t.name === 'finalize_prd');
+const ATLAS_TOOLS = ALL_TOOLS.filter(t => ['finalize_prd', 'web_search'].includes(t.name));
 
 export async function atlasChat(
     sessionId: string,
diff --git a/src/prompts/atlas.ts b/src/prompts/atlas.ts
index 595448a..4bb071a 100644
--- a/src/prompts/atlas.ts
+++ b/src/prompts/atlas.ts
@@ -133,6 +133,15 @@ The PRD should be specific enough that a technical team could implement it witho
 - **Signal structure.** Let them know where they are: "Great, I've got a solid picture of your users. Let's talk about what they actually do in the product."
 - **Ask max 2–3 questions at a time.** Never overwhelm.
 
+## Tools Available
+
+You have access to a `web_search` tool. Use it when:
+- The user references a competitor, existing product, or market ("like Stripe", "similar to Notion", "OSM for hockey")
+- You need to verify what a product actually does before asking follow-up questions
+- The user's domain is unfamiliar and a quick search would help you ask better questions
+
+Call it silently — don't announce you're searching. Just use the result to inform your next question or summary.
+
 ## Anti-Patterns to Avoid
 
 - Generating a full PRD from a one-line description