fix(sessions): clarify cross-agent visibility guidance (#90489)

sahibzada-allahyar · vincentkoc · web-flow · commit de60f4276793 · 2026-06-22T16:45:01.000Z
* fix(sessions): clarify cross-agent visibility guidance

* fix(sessions): clarify optional agent allow policy

---------

Co-authored-by: Vincent Koc &lt;vincentkoc@ieee.org&gt;
diff --git a/src/agents/tools/sessions-access.test.ts b/src/agents/tools/sessions-access.test.ts
@@ -278,7 +278,7 @@ describe("createSessionVisibilityGuard", () => {
       allowed: false,
       status: "forbidden",
       error:
-        "Session list visibility is restricted. Set tools.sessions.visibility=all to allow cross-agent access.",
+        "Session list visibility is restricted. Set tools.sessions.visibility=all and tools.agentToAgent.enabled=true to allow cross-agent access; use tools.agentToAgent.allow to restrict permitted agent pairs.",
     });
   });
 
@@ -340,7 +340,7 @@ describe("createSessionVisibilityGuard", () => {
       allowed: false,
       status: "forbidden",
       error:
-        "Session history visibility is restricted. Set tools.sessions.visibility=all to allow cross-agent access.",
+        "Session history visibility is restricted. Set tools.sessions.visibility=all and tools.agentToAgent.enabled=true to allow cross-agent access; use tools.agentToAgent.allow to restrict permitted agent pairs.",
     });
   });
 
diff --git a/src/plugin-sdk/session-visibility.ts b/src/plugin-sdk/session-visibility.ts
@@ -246,16 +246,18 @@ function a2aDeniedMessage(action: SessionAccessAction): string {
 }
 
 function crossVisibilityMessage(action: SessionAccessAction): string {
+  const suffix =
+    "Set tools.sessions.visibility=all and tools.agentToAgent.enabled=true to allow cross-agent access; use tools.agentToAgent.allow to restrict permitted agent pairs.";
   if (action === "history") {
-    return "Session history visibility is restricted. Set tools.sessions.visibility=all to allow cross-agent access.";
+    return `Session history visibility is restricted. ${suffix}`;
   }
   if (action === "send") {
-    return "Session send visibility is restricted. Set tools.sessions.visibility=all to allow cross-agent access.";
+    return `Session send visibility is restricted. ${suffix}`;
   }
   if (action === "status") {
-    return "Session status visibility is restricted. Set tools.sessions.visibility=all to allow cross-agent access.";
+    return `Session status visibility is restricted. ${suffix}`;
   }
-  return "Session list visibility is restricted. Set tools.sessions.visibility=all to allow cross-agent access.";
+  return `Session list visibility is restricted. ${suffix}`;
 }
 
 function selfVisibilityMessage(action: SessionAccessAction): string {

Original file line number	Diff line number	Diff line change
`@@ -246,16 +246,18 @@ function a2aDeniedMessage(action: SessionAccessAction): string {`
`246`	`246`	`}`
`247`	`247`
`248`	`248`	`function crossVisibilityMessage(action: SessionAccessAction): string {`
	`249`	`+ const suffix =`
	`250`	`+ "Set tools.sessions.visibility=all and tools.agentToAgent.enabled=true to allow cross-agent access; use tools.agentToAgent.allow to restrict permitted agent pairs.";`
`249`	`251`	`if (action === "history") {`
`250`		`- return "Session history visibility is restricted. Set tools.sessions.visibility=all to allow cross-agent access.";`
	`252`	+ return `Session history visibility is restricted. ${suffix}`;
`251`	`253`	`}`
`252`	`254`	`if (action === "send") {`
`253`		`- return "Session send visibility is restricted. Set tools.sessions.visibility=all to allow cross-agent access.";`
	`255`	+ return `Session send visibility is restricted. ${suffix}`;
`254`	`256`	`}`
`255`	`257`	`if (action === "status") {`
`256`		`- return "Session status visibility is restricted. Set tools.sessions.visibility=all to allow cross-agent access.";`
	`258`	+ return `Session status visibility is restricted. ${suffix}`;
`257`	`259`	`}`
`258`		`- return "Session list visibility is restricted. Set tools.sessions.visibility=all to allow cross-agent access.";`
	`260`	+ return `Session list visibility is restricted. ${suffix}`;
`259`	`261`	`}`
`260`	`262`
`261`	`263`	`function selfVisibilityMessage(action: SessionAccessAction): string {`