diff --git a/src/tools/delegate-task/subagent-resolver.ts b/src/tools/delegate-task/subagent-resolver.ts
index 1d67f24b4..104917c5a 100644
--- a/src/tools/delegate-task/subagent-resolver.ts
+++ b/src/tools/delegate-task/subagent-resolver.ts
@@ -60,6 +60,14 @@ Create the work plan directly - that's your job as the planning agent.`,
     }
   }
 
+  if (parentAgent && getAgentConfigKey(agentName) === getAgentConfigKey(parentAgent)) {
+    return {
+      agentToUse: "",
+      categoryModel: undefined,
+      error: `Cannot spawn "${agentName}" from within itself. Self-delegation creates infinite recursion. Use category-based delegation to spawn a Sisyphus-Junior worker instead (e.g., category="quick" or category="deep").`,
+    }
+  }
+
   let agentToUse = agentName
   let categoryModel: DelegatedModelConfig | undefined
   let fallbackChain: FallbackEntry[] | undefined = undefined
diff --git a/src/tools/delegate-task/sync-continuation.test.ts b/src/tools/delegate-task/sync-continuation.test.ts
index fa05e93ab..1f749e9f1 100644
--- a/src/tools/delegate-task/sync-continuation.test.ts
+++ b/src/tools/delegate-task/sync-continuation.test.ts
@@ -530,6 +530,7 @@ describe("executeSyncContinuation - toast cleanup error paths", () => {
       task: false,
       call_omo_agent: false,
       question: false,
+      switch_agent: false,
       write: false,
       edit: false,
     })
@@ -600,6 +601,7 @@ describe("executeSyncContinuation - toast cleanup error paths", () => {
       task: false,
       call_omo_agent: false,
       question: false,
+      switch_agent: false,
       write: false,
       edit: false,
     })