feat(wellness): add update_wellness write tool, computed Form (TSB), date-label fix

Add an update_wellness MCP tool that writes nutrition macros, hydration, vitals,
sleep, and subjective ratings to Intervals.icu via PUT /athlete/{id}/wellness/{date}.
Only provided fields are sent; pass -1 to clear a numeric field and locked=True to
stop device/app syncs from overwriting the values. Sleep is taken in hours and
stored as seconds (with -1 passing through as the clear sentinel).

Also surface computed Form (TSB = CTL - ATL) in wellness output, and prefer an
explicit `date` field over the record `id` for the Date label.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01NGzHtDvJur9U7ysgRKRUTN

tests/ressources/wellness_entry_formatted.txt

@@ -4,6 +4,7 @@ Date: 2025-05-24
 Training Metrics:
 - Fitness (CTL): 70.87253
 - Fatigue (ATL): 91.97159
+- Form (TSB): -21.1
 - Ramp Rate: 6.997368
 - CTL Load: 299
 - ATL Load: 299

tests/test_formatting.py

@@ -64,6 +64,24 @@ def test_format_wellness_entry():
     assert result == expected_result
 
 
+def test_format_wellness_entry_computes_form_tsb():
+    """Form (TSB) is computed as CTL - ATL when both are present."""
+    result = format_wellness_entry({"id": "2024-06-01", "ctl": 50, "atl": 65})
+    assert "Form (TSB): -15.0" in result
+
+
+def test_format_wellness_entry_no_form_without_both_components():
+    """Form is omitted if either CTL or ATL is missing."""
+    result = format_wellness_entry({"id": "2024-06-01", "ctl": 50})
+    assert "Form (TSB)" not in result
+
+
+def test_format_wellness_entry_prefers_explicit_date_over_id():
+    """An explicit `date` field wins over `id` for the Date line."""
+    result = format_wellness_entry({"id": "2024-06-01", "date": "2024-06-02", "ctl": 50})
+    assert "Date: 2024-06-02" in result
+
+
 def test_format_wellness_entry_include_all_fields():
     """
     Test that format_wellness_entry with include_all_fields=True includes additional unknown fields.

tests/test_wellness.py

@@ -0,0 +1,128 @@
+"""
+Tests for intervals_mcp_server.tools.wellness.
+
+Covers the wellness write tool (``update_wellness``): field mapping to the
+Intervals.icu camelCase schema, the sleep hours->seconds conversion and the
+``-1`` clear sentinel, request shape (PUT + path), the empty-payload guard, and
+the error / credential branches. The default caller credentials come from the
+autouse fixture in conftest (athlete ``i1``).
+"""
+
+import asyncio
+
+from intervals_mcp_server import credentials
+from intervals_mcp_server.credentials import CredentialError
+from intervals_mcp_server.tools import wellness
+
+
+def _patch_request(monkeypatch, result):
+    """Patch make_intervals_request; capture the call kwargs, return ``result``."""
+    calls: list[dict] = []
+
+    async def fake(**kwargs):
+        calls.append(kwargs)
+        return result
+
+    monkeypatch.setattr(wellness, "make_intervals_request", fake)
+    return calls
+
+
+def test_update_wellness_maps_fields_and_puts(monkeypatch):
+    calls = _patch_request(monkeypatch, {"id": "2025-05-24", "weight": 78})
+    out = asyncio.run(
+        wellness.update_wellness(
+            date="2025-05-24",
+            weight=78,
+            resting_hr=50,
+            hrv=65.5,
+            sleep_hours=8,
+            calories_consumed=2200,
+            carbohydrates=300,
+            protein=140,
+            fat=70,
+            hydration_volume=2.5,
+            comments="felt good",
+        )
+    )
+
+    assert len(calls) == 1
+    call = calls[0]
+    assert call["method"] == "PUT"
+    assert call["url"] == "/athlete/i1/wellness/2025-05-24"
+    assert call["api_key"] == "testkey"
+
+    payload = call["data"]
+    assert payload["weight"] == 78
+    assert payload["restingHR"] == 50
+    assert payload["hrv"] == 65.5
+    assert payload["sleepSecs"] == 8 * 3600  # hours -> seconds
+    assert payload["kcalConsumed"] == 2200
+    assert payload["carbohydrates"] == 300
+    assert payload["protein"] == 140
+    assert payload["fatTotal"] == 70
+    assert payload["hydrationVolume"] == 2.5
+    assert payload["comments"] == "felt good"
+    # Omitted fields must not be sent.
+    assert "mood" not in payload
+    assert "locked" not in payload
+
+    assert "Updated wellness for 2025-05-24" in out
+
+
+def test_update_wellness_defaults_date_to_today(monkeypatch):
+    calls = _patch_request(monkeypatch, {"id": "today"})
+    asyncio.run(wellness.update_wellness(weight=80))
+    # URL date segment defaults to today's date (YYYY-MM-DD, 10 chars).
+    date_seg = calls[0]["url"].rsplit("/", 1)[1]
+    assert len(date_seg) == 10 and date_seg.count("-") == 2
+
+
+def test_update_wellness_no_fields_returns_message(monkeypatch):
+    calls = _patch_request(monkeypatch, {})
+    out = asyncio.run(wellness.update_wellness(date="2025-05-24"))
+    assert "No wellness fields provided" in out
+    assert calls == []  # no request made
+
+
+def test_update_wellness_clear_with_negative_one(monkeypatch):
+    calls = _patch_request(monkeypatch, {"id": "2025-05-24"})
+    asyncio.run(wellness.update_wellness(date="2025-05-24", weight=-1, sleep_hours=-1))
+    payload = calls[0]["data"]
+    assert payload["weight"] == -1
+    # -1 is the clear sentinel and must NOT be scaled to -3600.
+    assert payload["sleepSecs"] == -1
+
+
+def test_update_wellness_locked_false_is_sent(monkeypatch):
+    calls = _patch_request(monkeypatch, {"id": "2025-05-24"})
+    asyncio.run(wellness.update_wellness(date="2025-05-24", locked=False))
+    assert calls[0]["data"]["locked"] is False
+
+
+def test_update_wellness_error_path(monkeypatch):
+    _patch_request(monkeypatch, {"error": True, "message": "boom"})
+    out = asyncio.run(wellness.update_wellness(date="2025-05-24", weight=80))
+    assert "Error updating wellness data: boom" in out
+
+
+def test_update_wellness_invalid_date(monkeypatch):
+    calls = _patch_request(monkeypatch, {})
+    out = asyncio.run(wellness.update_wellness(date="not-a-date", weight=80))
+    assert out.startswith("Error:")
+    assert calls == []
+
+
+def test_update_wellness_credential_error(monkeypatch):
+    async def _deny():
+        raise CredentialError("not approved")
+
+    monkeypatch.setattr(credentials, "resolve_caller_credentials", _deny)
+    out = asyncio.run(wellness.update_wellness(date="2025-05-24", weight=80))
+    assert "not approved" in out
+
+
+def test_update_wellness_non_dict_result(monkeypatch):
+    # If the API returns a list (unexpected), we still confirm the write.
+    _patch_request(monkeypatch, [])
+    out = asyncio.run(wellness.update_wellness(date="2025-05-24", weight=80))
+    assert out == "Updated wellness for 2025-05-24."