diff --git a/src/cli/boulder/formatter.test.ts b/src/cli/boulder/formatter.test.ts
new file mode 100644
index 000000000..cd787bf91
--- /dev/null
+++ b/src/cli/boulder/formatter.test.ts
@@ -0,0 +1,62 @@
+import { describe, expect, it } from "bun:test"
+
+import { formatJsonOutput, formatTextOutput } from "./formatter"
+import type { BoulderCliResult } from "./types"
+
+describe("boulder formatter", () => {
+  it("renders text output with statuses and progress", () => {
+    const result: BoulderCliResult = {
+      works: [
+        {
+          work_id: "w1",
+          plan_name: "alpha",
+          active_plan: "/tmp/alpha.md",
+          status: "active",
+          started_at: "2026-05-10T00:00:00.000Z",
+          elapsed_human: "30m 0s",
+          total_tasks: 2,
+          completed_tasks: 1,
+          remaining_tasks: 1,
+          percentage: 50,
+          session_count: 2,
+          current_task: {
+            task_key: "todo:2",
+            task_title: "Alpha task",
+            elapsed_human: "1m 0s",
+          },
+        },
+      ],
+    }
+
+    const textOutput = formatTextOutput(result)
+    expect(textOutput).toContain("boulder progress")
+    expect(textOutput).toContain("plan: alpha")
+    expect(textOutput).toContain("status: active")
+    expect(textOutput).toContain("progress: 50% (1/2)")
+    expect(textOutput).toContain("elapsed: 30m 0s")
+  })
+
+  it("renders parseable json output", () => {
+    const result: BoulderCliResult = {
+      works: [
+        {
+          work_id: "w1",
+          plan_name: "alpha",
+          active_plan: "/tmp/alpha.md",
+          status: "completed",
+          started_at: "2026-05-10T00:00:00.000Z",
+          ended_at: "2026-05-10T00:01:00.000Z",
+          elapsed_ms: 60_000,
+          total_tasks: 2,
+          completed_tasks: 2,
+          remaining_tasks: 0,
+          percentage: 100,
+          session_count: 1,
+        },
+      ],
+    }
+
+    const jsonOutput = formatJsonOutput(result)
+    expect(JSON.parse(jsonOutput)).toEqual(result)
+  })
+})
diff --git a/src/cli/boulder/formatter.ts b/src/cli/boulder/formatter.ts
new file mode 100644
index 000000000..94af0b603
--- /dev/null
+++ b/src/cli/boulder/formatter.ts
@@ -0,0 +1,75 @@
+import color from "picocolors"
+
+import type { BoulderWorkStatus } from "../../features/boulder-state"
+import type { BoulderCliResult, BoulderCliWork } from "./types"
+
+function colorizeStatus(status: BoulderWorkStatus): string {
+  if (status === "active") {
+    return color.cyan(status)
+  }
+
+  if (status === "completed") {
+    return color.green(status)
+  }
+
+  if (status === "paused") {
+    return color.yellow(status)
+  }
+
+  return color.red(status)
+}
+
+function formatCurrentTask(work: BoulderCliWork): string {
+  if (!work.current_task) {
+    return "-"
+  }
+
+  const elapsed = work.current_task.elapsed_human
+    ? ` (${work.current_task.elapsed_human})`
+    : ""
+  return `${work.current_task.task_title}${elapsed}`
+}
+
+function formatWorkBlock(work: BoulderCliWork): string {
+  const elapsed = work.elapsed_human ?? "-"
+  const progress = `${work.percentage}% (${work.completed_tasks}/${work.total_tasks})`
+
+  return [
+    `plan: ${work.plan_name}`,
+    `status: ${colorizeStatus(work.status)}`,
+    `progress: ${progress}`,
+    `elapsed: ${elapsed}`,
+    `sessions: ${work.session_count}`,
+    `current task: ${formatCurrentTask(work)}`,
+  ].join("\n")
+}
+
+export function formatTextOutput(result: BoulderCliResult): string {
+  const separator = color.dim("----------------------------------------")
+  const blocks = result.works.map((work) => formatWorkBlock(work))
+  return ["boulder progress", ...blocks].join(`\n${separator}\n`)
+}
+
+export function formatJsonOutput(result: BoulderCliResult): string {
+  return JSON.stringify(result, null, 2)
+}
+
+export function formatNoBoulderMessage(isJson: boolean | undefined): string {
+  if (isJson) {
+    return JSON.stringify({
+      error: "No boulder state found.",
+    })
+  }
+
+  return "No boulder state found."
+}
+
+export function formatReadErrorMessage(isJson: boolean | undefined): string {
+  if (isJson) {
+    return JSON.stringify({
+      error: "Failed to read boulder state.",
+    })
+  }
+
+  return "Failed to read boulder state."
+}
diff --git a/src/cli/boulder/types.ts b/src/cli/boulder/types.ts
new file mode 100644
index 000000000..adefc72c5
--- /dev/null
+++ b/src/cli/boulder/types.ts
@@ -0,0 +1,33 @@
+import type { BoulderWorkStatus } from "../../features/boulder-state"
+
+export interface BoulderOptions {
+  directory?: string
+  workId?: string
+  json?: boolean
+}
+
+export interface BoulderCliWork {
+  work_id: string
+  plan_name: string
+  active_plan: string
+  worktree_path?: string
+  status: BoulderWorkStatus
+  started_at: string
+  ended_at?: string
+  elapsed_human?: string
+  elapsed_ms?: number
+  total_tasks: number
+  completed_tasks: number
+  remaining_tasks: number
+  percentage: number
+  session_count: number
+  current_task?: {
+    task_key: string
+    task_title: string
+    elapsed_human?: string
+  }
+}
+
+export interface BoulderCliResult {
+  works: BoulderCliWork[]
+}