fix(agents): add anti-duplication rules to Atlas agent prompts

src/agents/atlas/atlas-prompt.test.ts

@@ -77,6 +77,21 @@ describe("Atlas prompts auto-continue policy", () => {
   })
 })
 
+describe("Atlas prompts anti-duplication coverage", () => {
+  test("all variants should include anti-duplication rules for delegated exploration", () => {
+    // given
+    const prompts = [ATLAS_SYSTEM_PROMPT, ATLAS_GPT_SYSTEM_PROMPT, ATLAS_GEMINI_SYSTEM_PROMPT]
+
+    // when / then
+    for (const prompt of prompts) {
+      expect(prompt).toContain("<Anti_Duplication>")
+      expect(prompt).toContain("Anti-Duplication Rule")
+      expect(prompt).toContain("DO NOT perform the same search yourself")
+      expect(prompt).toContain("non-overlapping work")
+    }
+  })
+})
+
 describe("Atlas prompts plan path consistency", () => {
   test("default variant should use .sisyphus/plans/{plan-name}.md path", () => {
     // given

src/agents/atlas/default.ts

@@ -8,6 +8,8 @@
  * - Extended reasoning sections
  */
 
+import { buildAntiDuplicationSection } from "../dynamic-agent-prompt-builder"
+
 export const ATLAS_SYSTEM_PROMPT = `
 <identity>
 You are Atlas - the Master Orchestrator from OhMyOpenCode.
@@ -24,6 +26,8 @@ Implementation tasks are the means. Final Wave approval is the goal.
 One task per delegation. Parallel when independent. Verify everything.
 </mission>
 
+${buildAntiDuplicationSection()}
+
 <delegation_system>
 ## How to Delegate
 

src/agents/atlas/gemini.ts

@@ -8,6 +8,8 @@
  * - Consequence-driven framing (Gemini ignores soft warnings)
  */
 
+import { buildAntiDuplicationSection } from "../dynamic-agent-prompt-builder"
+
 export const ATLAS_GEMINI_SYSTEM_PROMPT = `
 <identity>
 You are Atlas - Master Orchestrator from OhMyOpenCode.
@@ -51,6 +53,8 @@ Implementation tasks are the means. Final Wave approval is the goal.
 - **Your creativity should go into ORCHESTRATION QUALITY, not implementation decisions.**
 </scope_and_design_constraints>
 
+${buildAntiDuplicationSection()}
+
 <delegation_system>
 ## How to Delegate
 

src/agents/atlas/gpt.ts

@@ -8,6 +8,8 @@
  * - Scope discipline (no extra features)
  */
 
+import { buildAntiDuplicationSection } from "../dynamic-agent-prompt-builder"
+
 export const ATLAS_GPT_SYSTEM_PROMPT = `
 <identity>
 You are Atlas - Master Orchestrator from OhMyOpenCode.
@@ -61,6 +63,8 @@ Implementation tasks are the means. Final Wave approval is the goal.
   3. \`Read\` for changed files
 </tool_usage_rules>
 
+${buildAntiDuplicationSection()}
+
 <delegation_system>
 ## Delegation API