refactor mode selection into delegate tool that spawns subagents (#265)

test/agnostic/delegateEffort.ts

@@ -0,0 +1,53 @@
+import type { AgentResult, TestRunnerOptions, ValidationCheck } from "../utils.ts";
+import { defineFixture, getAgentOutput, getStructuredOutput } from "../utils.ts";
+
+/**
+ * delegateEffort test - validates effort selection for delegation.
+ *
+ * the orchestrator delegates to Plan mode with mini effort.
+ * validates that the subagent runs at mini effort (visible in agent logs
+ * as "effort=mini" or sonnet model selection for claude).
+ */
+
+// orchestrator runs at "auto" (opus) while delegating with "mini" (sonnet).
+// this tests that the delegate tool's effort parameter actually overrides
+// the model selection — if it were ignored, the subagent would also run at auto.
+const fixture = defineFixture(
+  {
+    prompt: `This is a simple task. Delegate to the Plan mode with MINI effort (this is a trivial task).
+Pass these instructions to the subagent:
+"Call set_output with the value 'EFFORT_TEST_PASSED'. Do not create plans or PRs. Just call set_output."`,
+    effort: "auto",
+    timeout: "5m",
+  },
+  { localOnly: true }
+);
+
+function validator(result: AgentResult): ValidationCheck[] {
+  const output = getStructuredOutput(result);
+  const agentOutput = getAgentOutput(result);
+
+  const setOutputCalled = output !== null;
+  const correctValue = setOutputCalled && /EFFORT_TEST_PASSED/i.test(output);
+
+  // the orchestrator runs at auto (effort=auto in its log line).
+  // the delegate tool should spawn the subagent at mini (effort=mini in its log line).
+  // if effort override works, we should see BOTH effort=auto AND effort=mini in the output.
+  const orchestratorEffort = /running \w+ with effort=auto/i.test(agentOutput);
+  const subagentEffort = /running \w+ with effort=mini/i.test(agentOutput);
+
+  return [
+    { name: "set_output", passed: setOutputCalled },
+    { name: "correct_value", passed: correctValue },
+    { name: "orchestrator_auto", passed: orchestratorEffort },
+    { name: "subagent_mini", passed: subagentEffort },
+  ];
+}
+
+export const test: TestRunnerOptions = {
+  name: "delegate-effort",
+  fixture,
+  validator,
+  env: { GITHUB_REPOSITORY: "pullfrog/test-repo" },
+  tags: ["agnostic"],
+};