diff --git a/README.md b/README.md
index f560a4f..4b955e1 100644
--- a/README.md
+++ b/README.md
@@ -123,8 +123,8 @@ View logs: `journalctl --user -u claude-usage-daemon -f`
 ## How it works
 
 1. The daemon reads your Claude Code OAuth token — from the macOS Keychain (service `Claude Code-credentials`) on macOS, or from `~/.claude/.credentials.json` on Linux.
-2. It GETs `api.anthropic.com/api/oauth/usage` (the same endpoint `claude /usage` uses) — costs zero tokens.
-3. The response is JSON with `five_hour`, `seven_day`, `seven_day_sonnet`, `seven_day_opus`, `extra_usage` blocks; each window carries a `utilization` (0..1) and `resets_at` (ISO8601).
+2. It makes a minimal API call to `api.anthropic.com/v1/messages` — one token of Haiku, basically free.
+3. The usage numbers come straight out of the response headers (`anthropic-ratelimit-unified-5h-utilization` and friends).
 4. The daemon connects to the ESP32 over BLE and writes a JSON payload to the GATT RX characteristic.
 5. The firmware parses it and updates the LVGL dashboard.
 6. The firmware also tracks the rate of change of session % over a 5-minute window and picks splash animations from the matching mood group.
diff --git a/daemon/claude-usage-daemon.sh b/daemon/claude-usage-daemon.sh
index a9f1110..0663904 100755
--- a/daemon/claude-usage-daemon.sh
+++ b/daemon/claude-usage-daemon.sh
@@ -1,10 +1,8 @@
 #!/bin/bash
 # Claude Usage Tracker Daemon (BLE)
-# Reads Claude Code OAuth token, polls usage via the OAuth usage endpoint
-# (api.anthropic.com/api/oauth/usage — same one `claude /usage` uses, costs
-# zero tokens), sends results to the ESP32 over BLE GATT.
+# Reads Claude Code OAuth token, polls usage via API, sends to ESP32 over BLE GATT.
 # Auto-connects and reconnects to the Claude Controller BLE device.
-# Dependencies: curl, awk, python3, bluetoothctl
+# Dependencies: curl, awk, bluetoothctl
 
 DEVICE_NAME="Claude Controller"
 DEVICE_MAC="${DEVICE_MAC:-}"  # auto-discovered if empty
@@ -196,56 +194,42 @@ write_gatt() {
 poll() {
     local token
     token=$(read_token) || { log "Error: could not read token"; return 1; }
+    local now
+    now=$(date +%s)
 
-    local body
-    body=$(curl -s \
-        "https://api.anthropic.com/api/oauth/usage" \
+    local headers
+    headers=$(curl -s -D - -o /dev/null \
+        "https://api.anthropic.com/v1/messages" \
         -H "Authorization: Bearer $token" \
+        -H "anthropic-version: 2023-06-01" \
         -H "anthropic-beta: oauth-2025-04-20" \
-        -H "Accept: application/json" \
+        -H "Content-Type: application/json" \
         -H "User-Agent: claude-code/2.1.5" \
+        -d '{"model":"claude-haiku-4-5-20251001","max_tokens":1,"messages":[{"role":"user","content":"hi"}]}' \
         2>/dev/null) || { log "Error: API call failed"; return 1; }
 
+    local s5h_util s5h_reset s7d_util s7d_reset status
+    s5h_util=$(echo "$headers" | grep -i "anthropic-ratelimit-unified-5h-utilization" | tr -d '\r' | awk '{print $2}')
+    s5h_reset=$(echo "$headers" | grep -i "anthropic-ratelimit-unified-5h-reset" | tr -d '\r' | awk '{print $2}')
+    s7d_util=$(echo "$headers" | grep -i "anthropic-ratelimit-unified-7d-utilization" | tr -d '\r' | awk '{print $2}')
+    s7d_reset=$(echo "$headers" | grep -i "anthropic-ratelimit-unified-7d-reset" | tr -d '\r' | awk '{print $2}')
+    status=$(echo "$headers" | grep -i "anthropic-ratelimit-unified-5h-status" | tr -d '\r' | awk '{print $2}')
+
+    s5h_util=${s5h_util:-0}
+    s5h_reset=${s5h_reset:-0}
+    s7d_util=${s7d_util:-0}
+    s7d_reset=${s7d_reset:-0}
+    status=${status:-unknown}
+
     local payload
-    payload=$(python3 -c '
-import datetime, json, sys, time
-
-try:
-    data = json.loads(sys.stdin.read())
-except json.JSONDecodeError:
-    sys.exit(1)
-
-def pct(w):
-    if not isinstance(w, dict):
-        return 0
-    u = w.get("utilization")
-    return int(round(u)) if isinstance(u, (int, float)) else 0
-
-def reset_mins(w):
-    if not isinstance(w, dict):
-        return -1
-    s = w.get("resets_at")
-    if not isinstance(s, str):
-        return -1
-    try:
-        ts = datetime.datetime.fromisoformat(s.replace("Z", "+00:00")).timestamp()
-    except ValueError:
-        return -1
-    m = (ts - time.time()) / 60.0
-    return int(round(m)) if m > 0 else 0
-
-fh = data.get("five_hour")
-sd = data.get("seven_day")
-s = pct(fh)
-print(json.dumps({
-    "s": s,
-    "sr": reset_mins(fh),
-    "w": pct(sd),
-    "wr": reset_mins(sd),
-    "st": "limited" if s >= 100 else "allowed",
-    "ok": True,
-}, separators=(",", ":")))
-' <<< "$body") || { log "Error: failed to parse usage JSON"; return 1; }
+    payload=$(awk -v u5="$s5h_util" -v r5="$s5h_reset" -v u7="$s7d_util" -v r7="$s7d_reset" -v st="$status" -v now="$now" \
+        'BEGIN {
+            sp = sprintf("%.0f", u5 * 100);
+            sr = (r5 - now) / 60; sr = sr > 0 ? sprintf("%.0f", sr) : 0;
+            wp = sprintf("%.0f", u7 * 100);
+            wr = (r7 - now) / 60; wr = wr > 0 ? sprintf("%.0f", wr) : 0;
+            printf "{\"s\":%s,\"sr\":%s,\"w\":%s,\"wr\":%s,\"st\":\"%s\",\"ok\":true}", sp, sr, wp, wr, st;
+        }')
 
     log "Sending: $payload"
     write_gatt "$RX_CHAR_PATH" "$payload" || { log "Write failed"; return 1; }
diff --git a/daemon/claude_usage_daemon.py b/daemon/claude_usage_daemon.py
index a660dbd..8484ba5 100755
--- a/daemon/claude_usage_daemon.py
+++ b/daemon/claude_usage_daemon.py
@@ -1,10 +1,9 @@
 #!/usr/bin/env python3
 """Claude Usage Tracker Daemon (BLE) — macOS port of claude-usage-daemon.sh.
 
-Polls the Claude OAuth usage endpoint (the same one Claude Code's `/usage`
-command uses) and writes a JSON payload to the ESP32 "Claude Controller"
-peripheral over a custom GATT service. Uses bleak (CoreBluetooth backend
-on macOS).
+Polls Claude API rate-limit headers and writes a JSON payload to the
+ESP32 "Claude Controller" peripheral over a custom GATT service. Uses
+bleak (CoreBluetooth backend on macOS).
 """
 
 import asyncio
@@ -16,7 +15,6 @@ import signal
 import subprocess
 import sys
 import time
-from datetime import datetime
 from pathlib import Path
 
 import httpx
@@ -38,12 +36,18 @@ KEYCHAIN_SERVICE = "Claude Code-credentials"
 CREDENTIALS_PATH = Path.home() / ".claude" / ".credentials.json"
 SAVED_ADDR_FILE = Path.home() / ".config" / "claude-usage-monitor" / "ble-address"
 
-API_URL = "https://api.anthropic.com/api/oauth/usage"
+API_URL = "https://api.anthropic.com/v1/messages"
 API_HEADERS_TEMPLATE = {
+    "anthropic-version": "2023-06-01",
     "anthropic-beta": "oauth-2025-04-20",
-    "Accept": "application/json",
+    "Content-Type": "application/json",
     "User-Agent": "claude-code/2.1.5",
 }
+API_BODY = {
+    "model": "claude-haiku-4-5-20251001",
+    "max_tokens": 1,
+    "messages": [{"role": "user", "content": "hi"}],
+}
 
 
 def log(msg: str) -> None:
@@ -153,40 +157,12 @@ async def scan_for_device() -> str | None:
     return None
 
 
-def _parse_iso8601(s: object) -> float | None:
-    if not isinstance(s, str) or not s:
-        return None
-    try:
-        return datetime.fromisoformat(s.replace("Z", "+00:00")).timestamp()
-    except ValueError:
-        return None
-
-
-def _window_pct(window: object) -> int:
-    if not isinstance(window, dict):
-        return 0
-    util = window.get("utilization")
-    if not isinstance(util, (int, float)):
-        return 0
-    return int(round(float(util)))
-
-
-def _window_reset_mins(window: object, now: float) -> int:
-    if not isinstance(window, dict):
-        return -1
-    ts = _parse_iso8601(window.get("resets_at"))
-    if ts is None:
-        return -1
-    mins = (ts - now) / 60.0
-    return int(round(mins)) if mins > 0 else 0
-
-
 async def poll_api(token: str) -> dict | None:
     headers = dict(API_HEADERS_TEMPLATE)
     headers["Authorization"] = f"Bearer {token}"
     try:
         async with httpx.AsyncClient(timeout=20.0) as http:
-            resp = await http.get(API_URL, headers=headers)
+            resp = await http.post(API_URL, headers=headers, json=API_BODY)
     except httpx.HTTPError as e:
         log(f"API call failed: {e}")
         return None
@@ -194,24 +170,34 @@ async def poll_api(token: str) -> dict | None:
         log(f"API HTTP {resp.status_code}: {resp.text[:200]}")
         return None
 
-    try:
-        body = resp.json()
-    except json.JSONDecodeError as e:
-        log(f"API returned non-JSON: {e}")
-        return None
+    def hdr(name: str, default: str = "0") -> str:
+        return resp.headers.get(name, default)
 
     now = time.time()
-    five_hour = body.get("five_hour")
-    seven_day = body.get("seven_day")
-    s_pct = _window_pct(five_hour)
-    return {
-        "s": s_pct,
-        "sr": _window_reset_mins(five_hour, now),
-        "w": _window_pct(seven_day),
-        "wr": _window_reset_mins(seven_day, now),
-        "st": "limited" if s_pct >= 100 else "allowed",
+
+    def reset_minutes(reset_ts: str) -> int:
+        try:
+            r = float(reset_ts)
+        except ValueError:
+            return 0
+        mins = (r - now) / 60.0
+        return int(round(mins)) if mins > 0 else 0
+
+    def pct(util: str) -> int:
+        try:
+            return int(round(float(util) * 100))
+        except ValueError:
+            return 0
+
+    payload = {
+        "s": pct(hdr("anthropic-ratelimit-unified-5h-utilization")),
+        "sr": reset_minutes(hdr("anthropic-ratelimit-unified-5h-reset")),
+        "w": pct(hdr("anthropic-ratelimit-unified-7d-utilization")),
+        "wr": reset_minutes(hdr("anthropic-ratelimit-unified-7d-reset")),
+        "st": hdr("anthropic-ratelimit-unified-5h-status", "unknown"),
         "ok": True,
     }
+    return payload
 
 
 class Session:
diff --git a/install.sh b/install.sh
index 0b323a4..2357258 100755
--- a/install.sh
+++ b/install.sh
@@ -11,7 +11,7 @@ echo ""
 
 # Check dependencies
 echo "[1/3] Checking dependencies..."
-for cmd in curl awk python3 bluetoothctl busctl; do
+for cmd in curl awk bluetoothctl busctl; do
     command -v "$cmd" >/dev/null || { echo "Error: $cmd is required but not installed"; exit 1; }
 done
 echo "  All dependencies found"