refactor(cli-workflow): reduce cmdStepRead cognitive complexity

Extract four helper functions from cmdStepRead to reduce cognitive
complexity from 27 to ≤15:
- loadStepDetail: Load and validate step detail node
- loadTurnData: Load all turn nodes and extract content
- selectTurnsForQuota: Select turns within quota (≥1 always shown)
- formatStepMarkdown: Assemble final markdown output

All 6 existing tests pass. Zero Biome warnings. CLAUDE.md compliant.

Fixes #487

README.md

@@ -80,7 +80,7 @@ Global options: `-V, --version`, `--format <json|yaml>`, `-h, --help`.
 | Group | Commands |
 |-------|----------|
 | **thread** | `start`, `exec`, `show`, `list`, `stop`, `cancel`, `read` |
-| **step** | `list`, `show`, `fork` |
+| **step** | `list`, `show`, `read`, `fork` |
 | **workflow** | `add`, `show`, `list` |
 | **cas** | `get`, `put`, `put-text`, `has`, `refs`, `walk`, `reindex`, `schema list`, `schema get` |
 | **setup** | Interactive or `--provider`, `--base-url`, `--api-key`, `--model`, `--agent` |

packages/cli-workflow/README.md

@@ -77,6 +77,7 @@ uwf thread stop 01ARZ3NDEKTSV4RRFFQ69G5FAV
 |---------|-------------|
 | `uwf step list <thread-id>` | List all steps in a thread chronologically |
 | `uwf step show <step-hash>` | Show step metadata and frontmatter |
+| `uwf step read <step-hash> [--quota <chars>]` | Read a step's turns as human-readable markdown |
 | `uwf step fork <step-hash>` | Fork a thread from a specific step |
 
 Examples:
@@ -84,6 +85,7 @@ Examples:
 ```bash
 uwf step list 01ARZ3NDEKTSV4RRFFQ69G5FAV
 uwf step show 32GCDE899RRQ3
+uwf step read 32GCDE899RRQ3 --quota 2000
 uwf step fork 32GCDE899RRQ3
 ```
 

packages/cli-workflow/src/__tests__/cas-exit-code.test.ts

@@ -0,0 +1,152 @@
+import { execSync } from "node:child_process";
+import { mkdir, rm } from "node:fs/promises";
+import { tmpdir } from "node:os";
+import { join } from "node:path";
+import { afterEach, beforeEach, describe, expect, test } from "vitest";
+import { cmdCasPutText } from "../commands/cas.js";
+
+let storageRoot: string;
+let uwfPath: string;
+
+beforeEach(async () => {
+  storageRoot = join(
+    tmpdir(),
+    `uwf-cas-exit-test-${Date.now()}-${Math.random().toString(36).slice(2)}`,
+  );
+  await mkdir(storageRoot, { recursive: true });
+
+  // Find the uwf CLI path
+  uwfPath = join(__dirname, "../../src/cli.ts");
+});
+
+afterEach(async () => {
+  await rm(storageRoot, { recursive: true, force: true });
+});
+
+type ExecResult = {
+  stdout: string;
+  stderr: string;
+  exitCode: number;
+};
+
+function execUwf(args: string[]): ExecResult {
+  try {
+    const stdout = execSync(`bun ${uwfPath} ${args.join(" ")}`, {
+      env: { ...process.env, WORKFLOW_STORAGE_ROOT: storageRoot },
+      encoding: "utf-8",
+      stdio: ["pipe", "pipe", "pipe"],
+    });
+    return { stdout, stderr: "", exitCode: 0 };
+  } catch (error: unknown) {
+    if (
+      error &&
+      typeof error === "object" &&
+      "stdout" in error &&
+      "stderr" in error &&
+      "status" in error
+    ) {
+      return {
+        stdout: (error.stdout as Buffer | string).toString(),
+        stderr: (error.stderr as Buffer | string).toString(),
+        exitCode: error.status as number,
+      };
+    }
+    throw error;
+  }
+}
+
+describe("uwf cas has CLI exit codes", () => {
+  test("exits 0 when hash exists", async () => {
+    // Setup: Create a temp storage root, put a text node, capture hash
+    const putResult = await cmdCasPutText(storageRoot, "test content");
+    const hash = putResult.hash;
+
+    // Execute: uwf cas has <hash>
+    const result = execUwf(["cas", "has", hash]);
+
+    // Assert: stdout contains {"exists":true}, exit code === 0
+    expect(result.stdout).toContain('"exists":true');
+    expect(result.exitCode).toBe(0);
+  });
+
+  test("exits 1 when hash does not exist", () => {
+    // Setup: Create a temp storage root (empty CAS store)
+    // Execute: uwf cas has NOSUCHHASH123
+    const result = execUwf(["cas", "has", "NOSUCHHASH123"]);
+
+    // Assert: stdout contains {"exists":false}, exit code === 1
+    expect(result.stdout).toContain('"exists":false');
+    expect(result.exitCode).toBe(1);
+  });
+
+  test("JSON output format unchanged for exists=true", async () => {
+    // Setup: Create store, put node
+    const putResult = await cmdCasPutText(storageRoot, "test");
+    const hash = putResult.hash;
+
+    // Execute: uwf cas has <hash>
+    const result = execUwf(["cas", "has", hash]);
+
+    // Assert: stdout JSON parses correctly to {exists: true}
+    const parsed = JSON.parse(result.stdout.trim());
+    expect(parsed).toEqual({ exists: true });
+  });
+
+  test("JSON output format unchanged for exists=false", () => {
+    // Setup: Create empty store
+    // Execute: uwf cas has INVALID
+    const result = execUwf(["cas", "has", "INVALID"]);
+
+    // Assert: stdout JSON parses correctly to {exists: false}
+    const parsed = JSON.parse(result.stdout.trim());
+    expect(parsed).toEqual({ exists: false });
+  });
+
+  test("YAML output format preserves exit code behavior for exists=true", async () => {
+    // Setup: Create store with node
+    const putResult = await cmdCasPutText(storageRoot, "test");
+    const hash = putResult.hash;
+
+    // Execute: uwf --format yaml cas has <hash>
+    const result = execUwf(["--format", "yaml", "cas", "has", hash]);
+
+    // Assert: exit code === 0, output is YAML format
+    expect(result.exitCode).toBe(0);
+    expect(result.stdout).toContain("exists:");
+    expect(result.stdout).toContain("true");
+  });
+
+  test("YAML output format preserves exit code behavior for exists=false", () => {
+    // Setup: Create empty store
+    // Execute: uwf --format yaml cas has INVALID
+    const result = execUwf(["--format", "yaml", "cas", "has", "INVALID"]);
+
+    // Assert: exit code === 1, output is YAML format
+    expect(result.exitCode).toBe(1);
+    expect(result.stdout).toContain("exists:");
+    expect(result.stdout).toContain("false");
+  });
+});
+
+describe("regression: other cas commands unaffected", () => {
+  test("uwf cas get still exits 1 on not-found with error message", () => {
+    // Execute: uwf cas get NOSUCHHASH
+    const result = execUwf(["cas", "get", "NOSUCHHASH"]);
+
+    // Assert: exit code === 1, stderr contains "Node not found"
+    expect(result.exitCode).toBe(1);
+    expect(result.stderr).toContain("Node not found");
+  });
+
+  test("uwf cas put-text behavior unchanged", () => {
+    // Execute: uwf cas put-text "hello"
+    const result = execUwf(["cas", "put-text", "hello"]);
+
+    // Assert: exit code === 0, returns hash
+    expect(result.exitCode).toBe(0);
+    const parsed = JSON.parse(result.stdout.trim());
+    expect(parsed).toHaveProperty("hash");
+    expect(typeof parsed.hash).toBe("string");
+    expect(parsed.hash.length).toBe(13); // Crockford Base32 XXH64 hash length
+  });
+});

packages/cli-workflow/src/__tests__/cas.test.ts

@@ -0,0 +1,74 @@
+import { mkdir, rm } from "node:fs/promises";
+import { tmpdir } from "node:os";
+import { join } from "node:path";
+import { afterEach, beforeEach, describe, expect, test } from "vitest";
+import { cmdCasHas, cmdCasPutText } from "../commands/cas.js";
+
+let storageRoot: string;
+
+beforeEach(async () => {
+  storageRoot = join(tmpdir(), `uwf-cas-test-${Date.now()}-${Math.random().toString(36).slice(2)}`);
+  await mkdir(storageRoot, { recursive: true });
+});
+
+afterEach(async () => {
+  await rm(storageRoot, { recursive: true, force: true });
+});
+
+describe("cmdCasHas", () => {
+  test("returns {exists: true} for existing hash", async () => {
+    // Setup: Create a test store, put a node, get its hash
+    const putResult = await cmdCasPutText(storageRoot, "test content");
+    const hash = putResult.hash;
+
+    // Execute: Call cmdCasHas with the valid hash
+    const result = await cmdCasHas(storageRoot, hash);
+
+    // Assert: Result equals {exists: true}
+    expect(result).toEqual({ exists: true });
+  });
+
+  test("returns {exists: false} for non-existent hash", async () => {
+    // Setup: Create an empty test store
+    // (storageRoot already created in beforeEach)
+
+    // Execute: Call cmdCasHas with an invalid hash
+    const result = await cmdCasHas(storageRoot, "INVALIDHASH12");
+
+    // Assert: Result equals {exists: false}
+    expect(result).toEqual({ exists: false });
+  });
+
+  test("does not throw for non-existent hash", async () => {
+    // Setup: Create an empty test store
+    // Execute & Assert: Does not throw, returns {exists: false}
+    await expect(cmdCasHas(storageRoot, "NOSUCHHASH123")).resolves.toEqual({
+      exists: false,
+    });
+  });
+
+  test("handles malformed hash gracefully", async () => {
+    // Setup: Create a test store
+    // Execute: Call cmdCasHas with a too-short hash
+    const result = await cmdCasHas(storageRoot, "xyz");
+
+    // Assert: Returns {exists: false} (store.has() returns false)
+    expect(result).toEqual({ exists: false });
+  });
+
+  test("handles empty hash string", async () => {
+    // Execute: Call cmdCasHas with an empty string
+    const result = await cmdCasHas(storageRoot, "");
+
+    // Assert: Returns {exists: false}
+    expect(result).toEqual({ exists: false });
+  });
+
+  test("handles hash with special characters", async () => {
+    // Execute: Call cmdCasHas with special characters
+    const result = await cmdCasHas(storageRoot, "HASH!@#");
+
+    // Assert: Returns {exists: false}
+    expect(result).toEqual({ exists: false });
+  });
+});

packages/cli-workflow/src/__tests__/step-read.test.ts

@@ -0,0 +1,519 @@
+import { mkdir, mkdtemp, rm } from "node:fs/promises";
+import { tmpdir } from "node:os";
+import { join } from "node:path";
+import { bootstrap, putSchema } from "@uncaged/json-cas";
+import { createFsStore } from "@uncaged/json-cas-fs";
+import type { CasRef } from "@uncaged/workflow-protocol";
+import { afterEach, beforeEach, describe, expect, test } from "vitest";
+import { cmdStepRead } from "../commands/step.js";
+import { registerUwfSchemas } from "../schemas.js";
+
+// ── schemas used in tests ────────────────────────────────────────────────────
+
+const TURN_SCHEMA = {
+  title: "hermes-turn",
+  type: "object" as const,
+  required: ["index", "role", "content"],
+  properties: {
+    index: { type: "integer" as const },
+    role: { type: "string" as const },
+    content: { type: "string" as const },
+    toolCalls: {
+      anyOf: [
+        { type: "array" as const, items: { type: "object" as const } },
+        { type: "null" as const },
+      ],
+    },
+    reasoning: { anyOf: [{ type: "string" as const }, { type: "null" as const }] },
+  },
+  additionalProperties: false,
+};
+
+const DETAIL_SCHEMA = {
+  title: "hermes-detail",
+  type: "object" as const,
+  required: ["sessionId", "model", "duration", "turnCount", "turns"],
+  properties: {
+    sessionId: { type: "string" as const },
+    model: { type: "string" as const },
+    duration: { type: "integer" as const },
+    turnCount: { type: "integer" as const },
+    turns: {
+      type: "array" as const,
+      items: { type: "string" as const, format: "cas_ref" },
+    },
+  },
+  additionalProperties: false,
+};
+
+// ── helpers ───────────────────────────────────────────────────────────────────
+
+async function registerDetailSchemas(store: ReturnType<typeof createFsStore>) {
+  await bootstrap(store);
+  const [turn, detail] = await Promise.all([
+    putSchema(store, TURN_SCHEMA),
+    putSchema(store, DETAIL_SCHEMA),
+  ]);
+  return { turn, detail };
+}
+
+function generateContent(size: number, prefix = "Content"): string {
+  const base = `${prefix} `;
+  const repeat = Math.ceil(size / base.length);
+  return base.repeat(repeat).slice(0, size);
+}
+
+// ── fixture ───────────────────────────────────────────────────────────────────
+
+let tmpDir: string;
+
+beforeEach(async () => {
+  tmpDir = await mkdtemp(join(tmpdir(), "cli-uwf-step-read-test-"));
+});
+
+afterEach(async () => {
+  await rm(tmpDir, { recursive: true, force: true });
+});
+
+// ── step read tests ───────────────────────────────────────────────────────────
+
+describe("step read", () => {
+  test("test 1: basic single-step read with 3 turns", async () => {
+    const casDir = join(tmpDir, "cas");
+    await mkdir(casDir, { recursive: true });
+    const store = createFsStore(casDir);
+    const schemas = await registerUwfSchemas(store);
+    const detailSchemas = await registerDetailSchemas(store);
+
+    const workflowHash = await store.put(schemas.workflow, {
+      name: "test-wf",
+      description: "desc",
+      roles: {
+        worker: {
+          description: "Worker",
+          goal: "You are a worker agent.",
+          capabilities: [],
+          procedure: "Do the work.",
+          output: "Summarize the work.",
+          meta: "placeholder00" as CasRef,
+        },
+      },
+      conditions: {},
+      graph: {},
+    });
+
+    const startHash = await store.put(schemas.startNode, {
+      workflow: workflowHash,
+      prompt: "Test task",
+    });
+
+    const outputHash = await store.put(schemas.workflow, {
+      name: "out",
+      description: "",
+      roles: {},
+      conditions: {},
+      graph: {},
+    });
+
+    // Create 3 turns
+    const turnHashes: CasRef[] = [];
+    for (let i = 1; i <= 3; i++) {
+      const content = `Turn ${i} content with some text to make it readable.`;
+      const turnHash = await store.put(detailSchemas.turn, {
+        index: i - 1,
+        role: "assistant",
+        content,
+        toolCalls: null,
+        reasoning: null,
+      });
+      turnHashes.push(turnHash);
+    }
+
+    const detailHash = await store.put(detailSchemas.detail, {
+      sessionId: "session-1",
+      model: "test-model",
+      duration: 1000,
+      turnCount: 3,
+      turns: turnHashes,
+    });
+
+    const stepHash = await store.put(schemas.stepNode, {
+      start: startHash,
+      prev: null,
+      role: "worker",
+      output: outputHash,
+      detail: detailHash,
+      agent: "uwf-test",
+    });
+
+    // Read step with large quota
+    const markdown = await cmdStepRead(tmpDir, stepHash, 10000);
+
+    // Assert structure
+    expect(markdown).toContain(`# Step ${stepHash}`);
+    expect(markdown).toContain("**Role:** worker");
+    expect(markdown).toContain("**Agent:** uwf-test");
+    expect(markdown).toContain("## Turn 1");
+    expect(markdown).toContain("## Turn 2");
+    expect(markdown).toContain("## Turn 3");
+    expect(markdown).toContain("Turn 1 content with some text to make it readable.");
+    expect(markdown).toContain("Turn 2 content with some text to make it readable.");
+    expect(markdown).toContain("Turn 3 content with some text to make it readable.");
+  });
+
+  test("test 2: quota enforcement - multiple turns", async () => {
+    const casDir = join(tmpDir, "cas");
+    await mkdir(casDir, { recursive: true });
+    const store = createFsStore(casDir);
+    const schemas = await registerUwfSchemas(store);
+    const detailSchemas = await registerDetailSchemas(store);
+
+    const workflowHash = await store.put(schemas.workflow, {
+      name: "test-wf",
+      description: "desc",
+      roles: {
+        worker: {
+          description: "Worker",
+          goal: "You are a worker agent.",
+          capabilities: [],
+          procedure: "Do the work.",
+          output: "Summarize the work.",
+          meta: "placeholder00" as CasRef,
+        },
+      },
+      conditions: {},
+      graph: {},
+    });
+
+    const startHash = await store.put(schemas.startNode, {
+      workflow: workflowHash,
+      prompt: "Test task",
+    });
+
+    const outputHash = await store.put(schemas.workflow, {
+      name: "out",
+      description: "",
+      roles: {},
+      conditions: {},
+      graph: {},
+    });
+
+    // Create 4 turns of ~300 chars each
+    const turnHashes: CasRef[] = [];
+    for (let i = 1; i <= 4; i++) {
+      const content = generateContent(300, `Turn${i}`);
+      const turnHash = await store.put(detailSchemas.turn, {
+        index: i - 1,
+        role: "assistant",
+        content,
+        toolCalls: null,
+        reasoning: null,
+      });
+      turnHashes.push(turnHash);
+    }
+
+    const detailHash = await store.put(detailSchemas.detail, {
+      sessionId: "session-1",
+      model: "test-model",
+      duration: 1000,
+      turnCount: 4,
+      turns: turnHashes,
+    });
+
+    const stepHash = await store.put(schemas.stepNode, {
+      start: startHash,
+      prev: null,
+      role: "worker",
+      output: outputHash,
+      detail: detailHash,
+      agent: "uwf-test",
+    });
+
+    // Read step with limited quota (700 chars)
+    const markdown = await cmdStepRead(tmpDir, stepHash, 700);
+
+    // Assert only most recent turns fit
+    expect(markdown).toContain(`# Step ${stepHash}`);
+    // Should have skip hint
+    expect(markdown).toContain("Earlier turns omitted");
+    // Should include at least Turn 4 (most recent)
+    expect(markdown).toContain("Turn4");
+    // Total length should respect quota (with tolerance for structural overhead)
+    expect(markdown.length).toBeLessThanOrEqual(900); // 700 quota + 200 buffer tolerance
+  });
+
+  test("test 3: minimal quota edge case - always show at least one turn", async () => {
+    const casDir = join(tmpDir, "cas");
+    await mkdir(casDir, { recursive: true });
+    const store = createFsStore(casDir);
+    const schemas = await registerUwfSchemas(store);
+    const detailSchemas = await registerDetailSchemas(store);
+
+    const workflowHash = await store.put(schemas.workflow, {
+      name: "test-wf",
+      description: "desc",
+      roles: {
+        worker: {
+          description: "Worker",
+          goal: "You are a worker agent.",
+          capabilities: [],
+          procedure: "Do the work.",
+          output: "Summarize the work.",
+          meta: "placeholder00" as CasRef,
+        },
+      },
+      conditions: {},
+      graph: {},
+    });
+
+    const startHash = await store.put(schemas.startNode, {
+      workflow: workflowHash,
+      prompt: "Test task",
+    });
+
+    const outputHash = await store.put(schemas.workflow, {
+      name: "out",
+      description: "",
+      roles: {},
+      conditions: {},
+      graph: {},
+    });
+
+    // Create 1 turn of 500 chars
+    const content = generateContent(500, "LongTurn");
+    const turnHash = await store.put(detailSchemas.turn, {
+      index: 0,
+      role: "assistant",
+      content,
+      toolCalls: null,
+      reasoning: null,
+    });
+
+    const detailHash = await store.put(detailSchemas.detail, {
+      sessionId: "session-1",
+      model: "test-model",
+      duration: 1000,
+      turnCount: 1,
+      turns: [turnHash],
+    });
+
+    const stepHash = await store.put(schemas.stepNode, {
+      start: startHash,
+      prev: null,
+      role: "worker",
+      output: outputHash,
+      detail: detailHash,
+      agent: "uwf-test",
+    });
+
+    // Read step with minimal quota (1 char)
+    const markdown = await cmdStepRead(tmpDir, stepHash, 1);
+
+    // Assert at least one turn is always shown
+    expect(markdown).toContain("LongTurn");
+    expect(markdown.length).toBeGreaterThan(1);
+  });
+
+  test("test 4: step with no detail field", async () => {
+    const casDir = join(tmpDir, "cas");
+    await mkdir(casDir, { recursive: true });
+    const store = createFsStore(casDir);
+    const schemas = await registerUwfSchemas(store);
+
+    const workflowHash = await store.put(schemas.workflow, {
+      name: "test-wf",
+      description: "desc",
+      roles: {
+        worker: {
+          description: "Worker",
+          goal: "You are a worker agent.",
+          capabilities: [],
+          procedure: "Do the work.",
+          output: "Summarize the work.",
+          meta: "placeholder00" as CasRef,
+        },
+      },
+      conditions: {},
+      graph: {},
+    });
+
+    const startHash = await store.put(schemas.startNode, {
+      workflow: workflowHash,
+      prompt: "Test task",
+    });
+
+    const outputHash = await store.put(schemas.workflow, {
+      name: "out",
+      description: "",
+      roles: {},
+      conditions: {},
+      graph: {},
+    });
+
+    const stepHash = await store.put(schemas.stepNode, {
+      start: startHash,
+      prev: null,
+      role: "worker",
+      output: outputHash,
+      detail: null,
+      agent: "uwf-test",
+    });
+
+    // Read step - should return metadata only (no error)
+    const markdown = await cmdStepRead(tmpDir, stepHash, 4000);
+
+    // Assert metadata is present
+    expect(markdown).toContain(`# Step ${stepHash}`);
+    expect(markdown).toContain("**Role:** worker");
+    expect(markdown).toContain("**Agent:** uwf-test");
+    // Should not have turn sections
+    expect(markdown).not.toContain("## Turn");
+  });
+
+  test("test 5: step with detail but no turns array", async () => {
+    const casDir = join(tmpDir, "cas");
+    await mkdir(casDir, { recursive: true });
+    const store = createFsStore(casDir);
+    const schemas = await registerUwfSchemas(store);
+    await registerDetailSchemas(store);
+
+    const workflowHash = await store.put(schemas.workflow, {
+      name: "test-wf",
+      description: "desc",
+      roles: {
+        worker: {
+          description: "Worker",
+          goal: "You are a worker agent.",
+          capabilities: [],
+          procedure: "Do the work.",
+          output: "Summarize the work.",
+          meta: "placeholder00" as CasRef,
+        },
+      },
+      conditions: {},
+      graph: {},
+    });
+
+    const startHash = await store.put(schemas.startNode, {
+      workflow: workflowHash,
+      prompt: "Test task",
+    });
+
+    const outputHash = await store.put(schemas.workflow, {
+      name: "out",
+      description: "",
+      roles: {},
+      conditions: {},
+      graph: {},
+    });
+
+    // Create detail with different schema (no turns)
+    const SIMPLE_DETAIL_SCHEMA = {
+      title: "simple-detail",
+      type: "object" as const,
+      required: ["sessionId"],
+      properties: {
+        sessionId: { type: "string" as const },
+      },
+      additionalProperties: false,
+    };
+
+    await bootstrap(store);
+    const simpleDetailType = await putSchema(store, SIMPLE_DETAIL_SCHEMA);
+    const detailHash = await store.put(simpleDetailType, {
+      sessionId: "session-1",
+    });
+
+    const stepHash = await store.put(schemas.stepNode, {
+      start: startHash,
+      prev: null,
+      role: "worker",
+      output: outputHash,
+      detail: detailHash,
+      agent: "uwf-test",
+    });
+
+    // Read step - should return metadata only (no error)
+    const markdown = await cmdStepRead(tmpDir, stepHash, 4000);
+
+    // Assert metadata is present
+    expect(markdown).toContain(`# Step ${stepHash}`);
+    expect(markdown).toContain("**Role:** worker");
+    // Should not have turn sections
+    expect(markdown).not.toContain("## Turn");
+  });
+
+  test("test 6: turn content with special characters", async () => {
+    const casDir = join(tmpDir, "cas");
+    await mkdir(casDir, { recursive: true });
+    const store = createFsStore(casDir);
+    const schemas = await registerUwfSchemas(store);
+    const detailSchemas = await registerDetailSchemas(store);
+
+    const workflowHash = await store.put(schemas.workflow, {
+      name: "test-wf",
+      description: "desc",
+      roles: {
+        worker: {
+          description: "Worker",
+          goal: "You are a worker agent.",
+          capabilities: [],
+          procedure: "Do the work.",
+          output: "Summarize the work.",
+          meta: "placeholder00" as CasRef,
+        },
+      },
+      conditions: {},
+      graph: {},
+    });
+
+    const startHash = await store.put(schemas.startNode, {
+      workflow: workflowHash,
+      prompt: "Test task",
+    });
+
+    const outputHash = await store.put(schemas.workflow, {
+      name: "out",
+      description: "",
+      roles: {},
+      conditions: {},
+      graph: {},
+    });
+
+    // Create turn with special markdown characters
+    const content = "This has `backticks`, **bold**, *italic*, and [links](http://example.com)";
+    const turnHash = await store.put(detailSchemas.turn, {
+      index: 0,
+      role: "assistant",
+      content,
+      toolCalls: null,
+      reasoning: null,
+    });
+
+    const detailHash = await store.put(detailSchemas.detail, {
+      sessionId: "session-1",
+      model: "test-model",
+      duration: 1000,
+      turnCount: 1,
+      turns: [turnHash],
+    });
+
+    const stepHash = await store.put(schemas.stepNode, {
+      start: startHash,
+      prev: null,
+      role: "worker",
+      output: outputHash,
+      detail: detailHash,
+      agent: "uwf-test",
+    });
+
+    // Read step
+    const markdown = await cmdStepRead(tmpDir, stepHash, 4000);
+
+    // Assert content is rendered correctly without corruption
+    expect(markdown).toContain("`backticks`");
+    expect(markdown).toContain("**bold**");
+    expect(markdown).toContain("*italic*");
+    expect(markdown).toContain("[links](http://example.com)");
+  });
+});

packages/cli-workflow/src/cli.ts

@@ -16,7 +16,7 @@ import {
 import { cmdLogClean, cmdLogList, cmdLogShow } from "./commands/log.js";
 import { cmdSetup, cmdSetupInteractive } from "./commands/setup.js";
 import { cmdSkillCli } from "./commands/skill.js";
-import { cmdStepFork, cmdStepList, cmdStepShow } from "./commands/step.js";
+import { cmdStepFork, cmdStepList, cmdStepRead, cmdStepShow } from "./commands/step.js";
 import {
   cmdThreadCancel,
   cmdThreadExec,
@@ -346,7 +346,23 @@ step
     });
   });
 
-// step read is not yet registered (half-baked, see step.ts cmdStepRead)
+step
+  .command("read")
+  .description("Read a step's turns as human-readable markdown")
+  .argument("<step-hash>", "CAS hash of the StepNode")
+  .option("--quota <chars>", "Max output characters", "4000")
+  .action((stepHash: string, opts: { quota: string }) => {
+    const storageRoot = resolveStorageRoot();
+    runAction(async () => {
+      const quota = Number.parseInt(opts.quota, 10);
+      if (!Number.isFinite(quota) || quota < 1) {
+        process.stderr.write("invalid --quota: must be a positive integer\n");
+        process.exit(1);
+      }
+      const markdown = await cmdStepRead(storageRoot, stepHash as CasRef, quota);
+      process.stdout.write(markdown.endsWith("\n") ? markdown : `${markdown}\n`);
+    });
+  });
 
 step
   .command("fork")
@@ -549,7 +565,11 @@ cas
   .action((hash: string) => {
     const storageRoot = resolveStorageRoot();
     runAction(async () => {
-      writeOutput(await cmdCasHas(storageRoot, hash));
+      const result = await cmdCasHas(storageRoot, hash);
+      writeOutput(result);
+      if (!result.exists) {
+        process.exit(1);
+      }
     });
   });
 

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

@@ -1,3 +1,4 @@
+import type { BootstrapCapableStore } from "@uncaged/json-cas";
 import type {
   CasRef,
   StartEntry,
@@ -18,6 +19,11 @@ import {
   walkChain,
 } from "./shared.js";
 
+type TurnData = {
+  index: number;
+  content: string;
+};
+
 /**
  * List all steps in a thread (previously: thread steps)
  */
@@ -111,13 +117,114 @@ export async function cmdStepFork(
 }
 
 /**
- * Read a step's agent output as markdown (new command - requires #462)
- * TODO: Implement once unified agent detail/turn schema is available
+ * Load and validate step detail node from CAS store
+ */
+function loadStepDetail(store: BootstrapCapableStore, detailRef: CasRef): Record<string, unknown> {
+  const detailNode = store.get(detailRef);
+  if (detailNode === null) {
+    fail(`detail node not found: ${detailRef}`);
+  }
+  return detailNode.payload as Record<string, unknown>;
+}
+
+/**
+ * Load all turn nodes from CAS store and extract content
+ */
+function loadTurnData(store: BootstrapCapableStore, turns: unknown): TurnData[] {
+  if (!Array.isArray(turns) || turns.length === 0) {
+    return [];
+  }
+
+  const turnData: TurnData[] = [];
+  for (const turnRef of turns) {
+    if (typeof turnRef !== "string") {
+      continue;
+    }
+    const turnNode = store.get(turnRef as CasRef);
+    if (turnNode === null) {
+      continue;
+    }
+    const turn = turnNode.payload as Record<string, unknown>;
+    if (typeof turn.content === "string") {
+      turnData.push({
+        index: typeof turn.index === "number" ? turn.index : turnData.length,
+        content: turn.content,
+      });
+    }
+  }
+  return turnData;
+}
+
+/**
+ * Select turns that fit within quota, working backwards from most recent
+ */
+function selectTurnsForQuota(turnData: TurnData[], availableQuota: number): TurnData[] {
+  const selectedTurns: TurnData[] = [];
+  let totalChars = 0;
+
+  for (let i = turnData.length - 1; i >= 0; i--) {
+    const turn = turnData[i];
+    if (turn === undefined) continue;
+
+    const turnHeader = `## Turn ${turn.index + 1}\n\n`;
+    const turnBlock = turnHeader + turn.content;
+    const separatorCost = selectedTurns.length > 0 ? 2 : 0;
+    const addCost = turnBlock.length + separatorCost;
+
+    if (totalChars + addCost > availableQuota && selectedTurns.length > 0) {
+      break;
+    }
+
+    selectedTurns.unshift(turn);
+    totalChars += addCost;
+  }
+
+  return selectedTurns;
+}
+
+/**
+ * Assemble final markdown output from header and selected turns
+ */
+function formatStepMarkdown(
+  stepHash: CasRef,
+  role: string,
+  agent: string,
+  turnData: TurnData[],
+  selectedTurns: TurnData[],
+): string {
+  const parts: string[] = [];
+  parts.push(`# Step ${stepHash}`);
+  parts.push("");
+  parts.push(`**Role:** ${role}`);
+  parts.push(`**Agent:** ${agent}`);
+
+  if (selectedTurns.length === 0) {
+    return parts.join("\n");
+  }
+
+  const skippedCount = turnData.length - selectedTurns.length;
+  if (skippedCount > 0) {
+    parts.push("");
+    parts.push(`_[Earlier turns omitted due to quota. Use --quota to increase.]_`);
+  }
+
+  for (const turn of selectedTurns) {
+    parts.push("");
+    parts.push(`## Turn ${turn.index + 1}`);
+    parts.push("");
+    parts.push(turn.content);
+  }
+
+  return parts.join("\n");
+}
+
+/**
+ * Read a step's agent turns as human-readable markdown with quota enforcement
  */
 export async function cmdStepRead(
   storageRoot: string,
   stepHash: CasRef,
-  _before: number | null = null,
+  quota: number,
 ): Promise<string> {
   const uwf = await createUwfStore(storageRoot);
   const node = uwf.store.get(stepHash);
@@ -128,18 +235,22 @@ export async function cmdStepRead(
     fail(`node ${stepHash} is not a StepNode`);
   }
   const payload = node.payload as StepNodePayload;
-  if (!payload.output) {
-    fail(`step ${stepHash} has no output`);
+
+  if (payload.detail === null) {
+    return formatStepMarkdown(stepHash, payload.role, payload.agent, [], []);
   }
 
-  // TODO: Implement progressive turn reading with --before N
-  // For now, return a placeholder
-  const outputNode = uwf.store.get(payload.output);
-  if (outputNode === null) {
-    fail(`output node not found: ${payload.output}`);
+  const detail = loadStepDetail(uwf.store, payload.detail);
+  const turnData = loadTurnData(uwf.store, detail.turns);
+
+  if (turnData.length === 0) {
+    return formatStepMarkdown(stepHash, payload.role, payload.agent, [], []);
   }
 
-  // Return the output as JSON for now
-  // Once #462 is implemented, this will properly format frontmatter + markdown
-  return JSON.stringify(outputNode.payload, null, 2);
+  const headerSection = formatStepMarkdown(stepHash, payload.role, payload.agent, [], []);
+  const BUFFER = 200;
+  const availableQuota = quota - headerSection.length - BUFFER;
+  const selectedTurns = selectTurnsForQuota(turnData, availableQuota);
+
+  return formatStepMarkdown(stepHash, payload.role, payload.agent, turnData, selectedTurns);
 }

packages/workflow-agent-claude-code/__tests__/claude-code.test.ts

@@ -39,7 +39,7 @@ describe("buildClaudeCodePrompt", () => {
     expect(result).toContain("## Task\nFix the bug");
   });
 
-  test("includes previous steps as history summary", () => {
+  test("includes previous steps with content on first visit", () => {
     const ctx = makeCtx({
       steps: [
         {
@@ -48,18 +48,50 @@ describe("buildClaudeCodePrompt", () => {
           agent: "hermes",
           detail: "detail-1",
           edgePrompt: "Create a plan.",
+          content: "Here is my detailed plan for doing X.",
         },
       ],
     });
     const result = buildClaudeCodePrompt(ctx);
-    expect(result).toContain("## Previous Steps");
+    expect(result).toContain("## What Happened Since Your Last Turn");
     expect(result).toContain("Step 1: planner");
     expect(result).toContain("do X");
+    // First visit should include step content
+    expect(result).toContain("Here is my detailed plan for doing X.");
+  });
+
+  test("re-entry shows steps since last visit without content", () => {
+    const ctx = makeCtx({
+      isFirstVisit: false,
+      steps: [
+        {
+          role: "developer",
+          output: '{"status":"done"}',
+          agent: "claude-code",
+          detail: "detail-1",
+          edgePrompt: "Implement.",
+          content: "I implemented everything.",
+        },
+        {
+          role: "reviewer",
+          output: '{"approved":false}',
+          agent: "claude-code",
+          detail: "detail-2",
+          edgePrompt: "Review.",
+          content: "Rejected: complexity too high, refactor cmdStepRead.",
+        },
+      ],
+    });
+    const result = buildClaudeCodePrompt(ctx);
+    expect(result).toContain("## What Happened Since Your Last Turn");
+    expect(result).toContain("reviewer");
+    expect(result).toContain("approved");
   });
 
   test("omits history section when steps array is empty", () => {
     const result = buildClaudeCodePrompt(makeCtx({ steps: [] }));
-    expect(result).not.toContain("## Previous Steps");
+    expect(result).not.toContain("## What Happened Since Your Last Turn");
+    expect(result).toContain("## Current Instruction");
   });
 
   test("works without outputFormatInstruction", () => {

packages/workflow-agent-claude-code/src/claude-code.ts

@@ -3,6 +3,7 @@ import type { Store } from "@uncaged/json-cas";
 import {
   type AgentContext,
   type AgentRunResult,
+  buildContinuationPrompt,
   buildRolePrompt,
   createAgent,
   getCachedSessionId,
@@ -18,25 +19,6 @@ const CLAUDE_COMMAND = "claude";
 const CLAUDE_MAX_TURNS = 90;
 const CLAUDE_MODEL = process.env.CLAUDE_MODEL ?? null;
 
-function buildHistorySummary(steps: AgentContext["steps"]): string {
-  if (steps.length === 0) {
-    return "";
-  }
-
-  const lines: string[] = ["## Previous Steps"];
-  for (let i = 0; i < steps.length; i++) {
-    const step = steps[i];
-    if (step === undefined) {
-      continue;
-    }
-    lines.push("");
-    lines.push(`### Step ${i + 1}: ${step.role}`);
-    lines.push(`Output: ${JSON.stringify(step.output)}`);
-    lines.push(`Agent: ${step.agent}`);
-  }
-  return lines.join("\n");
-}
-
 /** Assemble system prompt, task, and prior step outputs for Claude Code. */
 export function buildClaudeCodePrompt(ctx: AgentContext): string {
   const roleDef = ctx.workflow.roles[ctx.role];
@@ -46,11 +28,23 @@ export function buildClaudeCodePrompt(ctx: AgentContext): string {
     parts.push(ctx.outputFormatInstruction, "");
   }
   parts.push(rolePrompt, "", "## Task", ctx.start.prompt);
-  const historyBlock = buildHistorySummary(ctx.steps);
-  if (historyBlock !== "") {
-    parts.push("", historyBlock);
+
+  if (!ctx.isFirstVisit) {
+    // Re-entry (session will be resumed): show only steps since last visit, meta only
+    parts.push("", buildContinuationPrompt(ctx.steps, ctx.role, ctx.edgePrompt));
+  } else if (ctx.steps.length > 0) {
+    // First visit: show all steps with content for recent ones
+    parts.push(
+      "",
+      buildContinuationPrompt(ctx.steps, ctx.role, ctx.edgePrompt, {
+        includeContent: true,
+        quota: 32000,
+      }),
+    );
+  } else {
+    parts.push("", "## Current Instruction", "", ctx.edgePrompt);
   }
-  parts.push("", "## Current Instruction", "", ctx.edgePrompt);
+
   return parts.join("\n");
 }