fix: prefer sessionKey over label instead of rejecting both in sessions_send

he-yufeng · he-yufeng · commit 5e5f3b826a02 · 2026-03-10T00:32:38.000+08:00
LLMs consistently provide both optional sessionKey and label params when calling sessions_send, triggering an unnecessary "Provide either sessionKey or label (not both)" error. This breaks agent-to-agent communication across multiple models (GPT, Kimi, DeepSeek). When both are provided, prefer sessionKey and ignore label — the existing fallback logic already handles the label-only path correctly. Fixes #41199 (sessions_send portion)
diff --git a/src/agents/tools/sessions-send-tool.ts b/src/agents/tools/sessions-send-tool.ts
@@ -63,14 +63,10 @@ export function createSessionsSendTool(opts?: {
       const sessionKeyParam = readStringParam(params, "sessionKey");
       const labelParam = readStringParam(params, "label")?.trim() || undefined;
       const labelAgentIdParam = readStringParam(params, "agentId")?.trim() || undefined;
-      if (sessionKeyParam && labelParam) {
-        return jsonResult({
-          runId: crypto.randomUUID(),
-          status: "error",
-          error: "Provide either sessionKey or label (not both).",
-        });
-      }
 
+      // When both sessionKey and label are provided, prefer sessionKey.
+      // LLMs frequently supply both optional params; rejecting that just
+      // causes unnecessary tool-call failures.
       let sessionKey = sessionKeyParam;
       if (!sessionKey && labelParam) {
         const requesterAgentId = resolveAgentIdFromSessionKey(effectiveRequesterKey);
