feat: add uwf skill cli command and Prepare section in role prompt

- Add 'uwf skill cli' command that prints markdown CLI reference
- buildRolePrompt now generates ## Prepare section:
  - Always prompts agent to run 'uwf skill cli' (explicit skill)
  - Renders capabilities as keyword hints for implicit skill loading

Fixes #369

packages/workflow-agent-kit/__tests__/build-role-prompt.test.ts

@@ -18,13 +18,16 @@ describe("buildRolePrompt", () => {
     expect(result).toContain("## Capabilities");
     expect(result).toContain("- cursor-agent");
     expect(result).toContain("- file-edit");
+    expect(result).toContain("## Prepare");
+    expect(result).toContain("uwf skill cli");
+    expect(result).toContain("cursor-agent, file-edit");
     expect(result).toContain("## Procedure");
     expect(result).toContain("Implement the feature.");
     expect(result).toContain("## Output");
     expect(result).toContain("Summarize changes.");
   });
 
-  test("empty fields are omitted", () => {
+  test("empty fields are omitted but Prepare is always present", () => {
     const role: RoleDefinition = {
       description: "A reviewer",
       goal: "You are a code reviewer.",
@@ -35,12 +38,14 @@ describe("buildRolePrompt", () => {
     };
     const result = buildRolePrompt(role);
     expect(result).toContain("## Goal");
+    expect(result).toContain("## Prepare");
+    expect(result).toContain("uwf skill cli");
     expect(result).toContain("## Procedure");
     expect(result).not.toContain("## Capabilities");
     expect(result).not.toContain("## Output");
   });
 
-  test("all empty returns empty string", () => {
+  test("all empty still includes Prepare section", () => {
     const role: RoleDefinition = {
       description: "Minimal",
       goal: "",
@@ -50,7 +55,12 @@ describe("buildRolePrompt", () => {
       meta: "placeholder00000" as string,
     };
     const result = buildRolePrompt(role);
-    expect(result).toBe("");
+    expect(result).toContain("## Prepare");
+    expect(result).toContain("uwf skill cli");
+    expect(result).not.toContain("## Goal");
+    expect(result).not.toContain("## Capabilities");
+    expect(result).not.toContain("## Procedure");
+    expect(result).not.toContain("## Output");
   });
 
   test("capabilities rendered as bullet list", () => {

packages/workflow-agent-kit/src/build-role-prompt.ts

@@ -3,8 +3,12 @@ import type { RoleDefinition } from "@uncaged/workflow-protocol";
 /**
  * Build the role prompt from a RoleDefinition.
  *
- * Assembles structured sections: Goal, Capabilities, Procedure, Output.
+ * Assembles structured sections: Goal, Capabilities, Prepare, Procedure, Output.
  * Empty strings and empty arrays are omitted from the output.
+ *
+ * The Prepare section always instructs the agent to run `uwf skill cli` to load
+ * workflow knowledge, plus renders the capabilities array as keyword hints for
+ * implicit skill loading.
  */
 export function buildRolePrompt(role: RoleDefinition): string {
   const sections: string[] = [];
@@ -18,6 +22,22 @@ export function buildRolePrompt(role: RoleDefinition): string {
     sections.push(`## Capabilities\n\n${list}`);
   }
 
+  const prepareLines: string[] = [
+    "Run the following command to load workflow CLI knowledge before starting work:",
+    "",
+    "```",
+    "uwf skill cli",
+    "```",
+  ];
+  if (role.capabilities.length > 0) {
+    const keywords = role.capabilities.join(", ");
+    prepareLines.push(
+      "",
+      `You have the following capabilities: ${keywords}. Load relevant skills matching these keywords before starting work.`,
+    );
+  }
+  sections.push(`## Prepare\n\n${prepareLines.join("\n")}`);
+
   if (role.procedure !== "") {
     sections.push(`## Procedure\n\n${role.procedure}`);
   }