refactor(agents): split tools + PI subscribe

src/agents/pi-tools.abort.ts

@@ -0,0 +1,43 @@
+import type { AnyAgentTool } from "./pi-tools.types.js";
+
+function throwAbortError(): never {
+  const err = new Error("Aborted");
+  err.name = "AbortError";
+  throw err;
+}
+
+function combineAbortSignals(
+  a?: AbortSignal,
+  b?: AbortSignal,
+): AbortSignal | undefined {
+  if (!a && !b) return undefined;
+  if (a && !b) return a;
+  if (b && !a) return b;
+  if (a?.aborted) return a;
+  if (b?.aborted) return b;
+  if (typeof AbortSignal.any === "function") {
+    return AbortSignal.any([a as AbortSignal, b as AbortSignal]);
+  }
+  const controller = new AbortController();
+  const onAbort = () => controller.abort();
+  a?.addEventListener("abort", onAbort, { once: true });
+  b?.addEventListener("abort", onAbort, { once: true });
+  return controller.signal;
+}
+
+export function wrapToolWithAbortSignal(
+  tool: AnyAgentTool,
+  abortSignal?: AbortSignal,
+): AnyAgentTool {
+  if (!abortSignal) return tool;
+  const execute = tool.execute;
+  if (!execute) return tool;
+  return {
+    ...tool,
+    execute: async (toolCallId, params, signal, onUpdate) => {
+      const combined = combineAbortSignals(signal, abortSignal);
+      if (combined?.aborted) throwAbortError();
+      return await execute(toolCallId, params, combined, onUpdate);
+    },
+  };
+}