refactor: rename status to $status, default to _ when absent

- evaluate() reads $status instead of status, defaults to _ when missing
- Update all YAML examples and .workflows to use $status
- Update cli-workflow resolveEvaluateArgs to use $status
- 10 moderator tests pass including new default _ test
- Single-exit roles no longer need to declare status field

Phase 1 of #499 (closes #500)

packages/cli-workflow/src/__tests__/solve-issue-tea-worktree.test.ts

@@ -81,7 +81,7 @@ describe("solve-issue workflow: tea pr create worktree fix", () => {
     expect(workflow.roles.committer?.frontmatter).toBeDefined();
   });
 
-  test("committer frontmatter schema should require status field", async () => {
+  test("committer frontmatter schema should require $status field", async () => {
     const yamlContent = await readFile(workflowPath, "utf-8");
     // Parse as any to access the raw YAML structure (frontmatter is inline JSON Schema in YAML)
     // eslint-disable-next-line @typescript-eslint/no-explicit-any
@@ -90,8 +90,8 @@ describe("solve-issue workflow: tea pr create worktree fix", () => {
     const frontmatter = workflow.roles.committer?.frontmatter;
     expect(frontmatter).toBeDefined();
     expect(frontmatter?.type).toBe("object");
-    expect(frontmatter?.properties?.status).toBeDefined();
-    expect(frontmatter?.properties?.status?.enum).toContain("committed");
-    expect(frontmatter?.required).toContain("status");
+    expect(frontmatter?.properties?.["$status"]).toBeDefined();
+    expect(frontmatter?.properties?.["$status"]?.enum).toContain("committed");
+    expect(frontmatter?.required).toContain("$status");
   });
 });

packages/cli-workflow/src/commands/thread.ts

@@ -669,14 +669,16 @@ function formatThreadReadMarkdown(options: {
   return parts.join("\n\n---\n\n");
 }
 
-type EvaluateLastOutput = Record<string, unknown> & { status: string };
+type EvaluateLastOutput = Record<string, unknown>;
+
+const STATUS_KEY = "$status";
 
 function resolveEvaluateArgs(
   uwf: UwfStore,
   chain: ChainState,
 ): { lastRole: string; lastOutput: EvaluateLastOutput } {
   if (chain.headIsStart) {
-    return { lastRole: START_ROLE, lastOutput: { status: "_" } };
+    return { lastRole: START_ROLE, lastOutput: { [STATUS_KEY]: "_" } };
   }
 
   const lastStep = chain.stepsNewestFirst[0];
@@ -689,11 +691,10 @@ function resolveEvaluateArgs(
     typeof raw === "object" && raw !== null && !Array.isArray(raw)
       ? (raw as Record<string, unknown>)
       : {};
-  const status = typeof base.status === "string" ? base.status : "_";
 
   return {
     lastRole: lastStep.role,
-    lastOutput: { ...base, status },
+    lastOutput: base,
   };
 }
 

packages/workflow-moderator/__tests__/evaluate.test.ts

@@ -21,7 +21,7 @@ const solveIssueGraph: WorkflowPayload["graph"] = {
 
 describe("evaluate", () => {
   test("$START → first role (unit status _)", () => {
-    const result = evaluate(solveIssueGraph, "$START", { status: "_" });
+    const result = evaluate(solveIssueGraph, "$START", { $status: "_" });
     expect(result).toEqual({
       ok: true,
       value: { role: "planner", prompt: "Start planning from the issue in the task." },
@@ -30,7 +30,7 @@ describe("evaluate", () => {
 
   test("status-based routing (reviewer rejected → developer)", () => {
     const result = evaluate(solveIssueGraph, "reviewer", {
-      status: "rejected",
+      $status: "rejected",
       comments: "missing tests",
     });
     expect(result).toEqual({
@@ -40,7 +40,7 @@ describe("evaluate", () => {
   });
 
   test("status-based routing (reviewer approved → $END)", () => {
-    const result = evaluate(solveIssueGraph, "reviewer", { status: "approved" });
+    const result = evaluate(solveIssueGraph, "reviewer", { $status: "approved" });
     expect(result).toEqual({
       ok: true,
       value: { role: "$END", prompt: "Done." },
@@ -48,7 +48,7 @@ describe("evaluate", () => {
   });
 
   test("missing role in graph → error", () => {
-    const result = evaluate(solveIssueGraph, "unknown-role", { status: "_" });
+    const result = evaluate(solveIssueGraph, "unknown-role", { $status: "_" });
     expect(result.ok).toBe(false);
     if (!result.ok) {
       expect(result.error.message).toBe('no transitions defined for role "unknown-role"');
@@ -56,7 +56,7 @@ describe("evaluate", () => {
   });
 
   test("missing status in graph → error", () => {
-    const result = evaluate(solveIssueGraph, "reviewer", { status: "pending" });
+    const result = evaluate(solveIssueGraph, "reviewer", { $status: "pending" });
     expect(result.ok).toBe(false);
     if (!result.ok) {
       expect(result.error.message).toBe('no transition for role "reviewer" with status "pending"');
@@ -65,7 +65,7 @@ describe("evaluate", () => {
 
   test("mustache template rendering with simple fields", () => {
     const result = evaluate(solveIssueGraph, "planner", {
-      status: "_",
+      $status: "_",
       plan: "Add auth middleware",
     });
     expect(result).toEqual({
@@ -76,7 +76,7 @@ describe("evaluate", () => {
 
   test("mustache does not HTML-escape prompt content", () => {
     const result = evaluate(solveIssueGraph, "reviewer", {
-      status: "rejected",
+      $status: "rejected",
       comments: 'use <T> & "Result<T, E>" types',
     });
     expect(result).toEqual({
@@ -92,7 +92,7 @@ describe("evaluate", () => {
       },
     };
     const result = evaluate(graph, "reviewer", {
-      status: "_",
+      $status: "_",
       comments: "<script>alert(1)</script>",
     });
     expect(result).toEqual({
@@ -101,6 +101,16 @@ describe("evaluate", () => {
     });
   });
 
+  test("missing $status defaults to _ (unit routing)", () => {
+    const result = evaluate(solveIssueGraph, "planner", {
+      plan: "Add auth middleware",
+    });
+    expect(result).toEqual({
+      ok: true,
+      value: { role: "developer", prompt: "Implement the plan: Add auth middleware" },
+    });
+  });
+
   test("mustache template with nested object paths", () => {
     const graph: Record<string, Record<string, Target>> = {
       reviewer: {
@@ -111,7 +121,7 @@ describe("evaluate", () => {
       },
     };
     const result = evaluate(graph, "reviewer", {
-      status: "_",
+      $status: "_",
       review: { comments: "refactor the handler" },
     });
     expect(result).toEqual({

packages/workflow-moderator/src/evaluate.ts

@@ -9,14 +9,21 @@ mustache.escape = (text: string) => text;
 const START_ROLE = "$START";
 const UNIT_STATUS = "_";
 
-type LastOutput = Record<string, unknown> & { status: string };
+type LastOutput = Record<string, unknown>;
+
+const STATUS_KEY = "$status";
 
 export function evaluate(
   graph: Record<string, Record<string, Target>>,
   lastRole: string,
   lastOutput: LastOutput,
 ): Result<EvaluateResult, Error> {
-  const status = lastRole === START_ROLE ? UNIT_STATUS : lastOutput.status;
+  const status =
+    lastRole === START_ROLE
+      ? UNIT_STATUS
+      : typeof lastOutput[STATUS_KEY] === "string"
+        ? (lastOutput[STATUS_KEY] as string)
+        : UNIT_STATUS;
 
   const roleTargets = graph[lastRole];
   if (roleTargets === undefined) {