diff --git a/src/agents/tools/sessions-history-tool.ts b/src/agents/tools/sessions-history-tool.ts
index 0cc378f7b..5288fc839 100644
--- a/src/agents/tools/sessions-history-tool.ts
+++ b/src/agents/tools/sessions-history-tool.ts
@@ -18,7 +18,7 @@ import {
 
 const SessionsHistoryToolSchema = Type.Object({
   sessionKey: Type.String(),
-  limit: Type.Optional(Type.Integer({ minimum: 1 })),
+  limit: Type.Optional(Type.Number({ minimum: 1 })),
   includeTools: Type.Optional(Type.Boolean()),
 });
 
diff --git a/src/agents/tools/sessions-list-tool.ts b/src/agents/tools/sessions-list-tool.ts
index 87108fad7..68e14506c 100644
--- a/src/agents/tools/sessions-list-tool.ts
+++ b/src/agents/tools/sessions-list-tool.ts
@@ -46,9 +46,9 @@ type SessionListRow = {
 
 const SessionsListToolSchema = Type.Object({
   kinds: Type.Optional(Type.Array(Type.String())),
-  limit: Type.Optional(Type.Integer({ minimum: 1 })),
-  activeMinutes: Type.Optional(Type.Integer({ minimum: 1 })),
-  messageLimit: Type.Optional(Type.Integer({ minimum: 0 })),
+  limit: Type.Optional(Type.Number({ minimum: 1 })),
+  activeMinutes: Type.Optional(Type.Number({ minimum: 1 })),
+  messageLimit: Type.Optional(Type.Number({ minimum: 0 })),
 });
 
 function resolveSandboxSessionToolsVisibility(
diff --git a/src/agents/tools/sessions-send-tool.ts b/src/agents/tools/sessions-send-tool.ts
index 1c6a06e93..7640d314b 100644
--- a/src/agents/tools/sessions-send-tool.ts
+++ b/src/agents/tools/sessions-send-tool.ts
@@ -30,25 +30,13 @@ import {
   resolvePingPongTurns,
 } from "./sessions-send-helpers.js";
 
-const SessionsSendToolSchema = Type.Union([
-  Type.Object(
-    {
-      sessionKey: Type.String(),
-      message: Type.String(),
-      timeoutSeconds: Type.Optional(Type.Integer({ minimum: 0 })),
-    },
-    { additionalProperties: false },
-  ),
-  Type.Object(
-    {
-      label: Type.String({ minLength: 1, maxLength: SESSION_LABEL_MAX_LENGTH }),
-      agentId: Type.Optional(Type.String({ minLength: 1, maxLength: 64 })),
-      message: Type.String(),
-      timeoutSeconds: Type.Optional(Type.Integer({ minimum: 0 })),
-    },
-    { additionalProperties: false },
-  ),
-]);
+const SessionsSendToolSchema = Type.Object({
+  sessionKey: Type.Optional(Type.String()),
+  label: Type.Optional(Type.String()),
+  agentId: Type.Optional(Type.String()),
+  message: Type.String(),
+  timeoutSeconds: Type.Optional(Type.Number({ minimum: 0 })),
+});
 
 export function createSessionsSendTool(opts?: {
   agentSessionKey?: string;
diff --git a/src/agents/tools/sessions-spawn-tool.ts b/src/agents/tools/sessions-spawn-tool.ts
index e6260a38a..f4391e5c3 100644
--- a/src/agents/tools/sessions-spawn-tool.ts
+++ b/src/agents/tools/sessions-spawn-tool.ts
@@ -25,9 +25,9 @@ const SessionsSpawnToolSchema = Type.Object({
   label: Type.Optional(Type.String()),
   agentId: Type.Optional(Type.String()),
   model: Type.Optional(Type.String()),
-  runTimeoutSeconds: Type.Optional(Type.Integer({ minimum: 0 })),
+  runTimeoutSeconds: Type.Optional(Type.Number({ minimum: 0 })),
   // Back-compat alias. Prefer runTimeoutSeconds.
-  timeoutSeconds: Type.Optional(Type.Integer({ minimum: 0 })),
+  timeoutSeconds: Type.Optional(Type.Number({ minimum: 0 })),
   cleanup: Type.Optional(
     Type.Union([Type.Literal("delete"), Type.Literal("keep")]),
   ),