test(agent): pin harness resource formatting

packages/agent/test/harness/resource-formatting.test.ts

@@ -0,0 +1,24 @@
+import { describe, expect, it } from "vitest";
+import { formatPromptTemplateInvocation } from "../../src/harness/prompt-templates.js";
+import { formatSkillInvocation } from "../../src/harness/skills.js";
+
+describe("resource formatting helpers", () => {
+	it("formats skill invocations with additional instructions", () => {
+		const skill = {
+			name: "inspect",
+			description: "Inspect things",
+			content: "Use inspection tools.",
+			filePath: "/project/.pi/skills/inspect/SKILL.md",
+		};
+
+		expect(formatSkillInvocation(skill, "Check errors.")).toBe(
+			'<skill name="inspect" location="/project/.pi/skills/inspect/SKILL.md">\nReferences are relative to /project/.pi/skills/inspect.\n\nUse inspection tools.\n</skill>\n\nCheck errors.',
+		);
+	});
+
+	it("formats prompt template invocations with positional arguments", () => {
+		expect(
+			formatPromptTemplateInvocation({ name: "review", content: "Review $1 with $ARGUMENTS" }, ["a.ts", "care"]),
+		).toBe("Review a.ts with a.ts care");
+	});
+});