Add basis_movement/basis_detail tools; make history + latest fully filterable

New MCP tools:
- basis_movement: aggregated basis trend, one headline line per crop. The cheap
  "how is basis moving overall" view; optional commodity/source/delivery/days.
- basis_detail: per-(elevator, crop, delivery) basis first→last drill-down.

Both do the aggregation MCP-side and return compact markdown to keep token
burn low, so a client can call the cheap aggregate first and drill in only when
needed.

Flexibility/parity changes:
- price_history: commodity is now optional (spans all crops); groups by
  (source, commodity, delivery); surfaces basis first→last in the summary and
  adds a futures column to the raw table.
- latest_prices: expose the `kind` filter (grain/fertilizer) that the API and
  client already supported.
- client.history(): commodity optional.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

ag_bids_mcp/server.py

@@ -103,41 +103,122 @@ def latest_prices(
         str | None,
         Field(description="Filter to one delivery label (e.g. 'May 2026', 'Oct/Nov 2026')."),
     ] = None,
+    kind: Annotated[
+        str | None,
+        Field(description="Filter to one commodity kind: 'grain' or 'fertilizer'. Omit for all."),
+    ] = None,
 ) -> str:
-    """Snapshot of the latest scraped bid per (source, commodity, delivery)."""
+    """Snapshot of the latest scraped bid per (source, commodity, delivery).
+
+    Every filter is optional and AND'd together — pivot by elevator, crop,
+    delivery, or kind in any combination."""
     cm = commodity.strip().lower() if commodity else None
-    with track("latest_prices", commodity=cm, source=source, delivery=delivery):
-        payload = client.latest(commodity=cm, source=source, delivery=delivery)
+    with track("latest_prices", commodity=cm, source=source, delivery=delivery, kind=kind):
+        payload = client.latest(commodity=cm, source=source, delivery=delivery, kind=kind)
         return fmt.fmt_latest(payload)
 
 
+def _filter_source(payload: dict, source: str | None) -> dict:
+    """Narrow a history payload's rows to one source display name, in place."""
+    if source:
+        payload["rows"] = [
+            r for r in payload.get("rows") or [] if r.get("source_name") == source
+        ]
+    return payload
+
+
 @mcp.tool()
 def price_history(
     commodity: Annotated[
-        str, Field(description="One of corn / soy / wheat / map / potash / lime.")
-    ],
+        str | None,
+        Field(description="Filter to one crop (corn / soy / wheat / map / potash / "
+                          "lime). Omit to span every crop."),
+    ] = None,
     source: Annotated[
         str | None,
-        Field(description="Optional source display name to narrow the chart."),
+        Field(description="Filter to one elevator by exact display name. Omit for all."),
     ] = None,
     delivery: Annotated[
         str | None,
-        Field(description="Optional delivery label to narrow the chart."),
+        Field(description="Filter to one delivery label (e.g. 'Jul 2026'). Omit for all."),
     ] = None,
     days: Annotated[
         int, Field(ge=1, le=365, description="Lookback window in days.")
     ] = 30,
 ) -> str:
-    """Compact price history per (source, delivery) for the chosen commodity.
+    """Price history per (elevator, crop, delivery), with every filter optional.
 
-    Returns per-series ▲/▼ trend annotations plus the raw points if the
-    window has fewer than ~60 samples."""
-    cm = commodity.strip().lower()
+    Pivot it however you like — one crop at one elevator, every elevator for one
+    crop, one delivery period across all crops, etc. Each series gets a ▲/▼ bid
+    trend plus its basis first→last; the raw bid/basis/futures points are
+    included when the window has fewer than ~60 samples."""
+    cm = commodity.strip().lower() if commodity else None
     with track("price_history", commodity=cm, source=source, delivery=delivery, days=days):
         payload = client.history(commodity=cm, delivery=delivery, days=days)
-        if source:
-            payload["rows"] = [r for r in payload.get("rows") or [] if r.get("source_name") == source]
-        return fmt.fmt_history(payload)
+        return fmt.fmt_history(_filter_source(payload, source))
+
+
+@mcp.tool()
+def basis_movement(
+    commodity: Annotated[
+        str | None,
+        Field(description="Filter to one grain (corn / soy / wheat). Omit to span all grains."),
+    ] = None,
+    source: Annotated[
+        str | None,
+        Field(description="Filter to one elevator by exact display name. Omit for all."),
+    ] = None,
+    delivery: Annotated[
+        str | None,
+        Field(description="Filter to one delivery label (e.g. 'Jul 2026'). Omit for all."),
+    ] = None,
+    days: Annotated[
+        int, Field(ge=1, le=365, description="Lookback window in days.")
+    ] = 30,
+) -> str:
+    """Aggregated basis trend — one headline line per crop (the cheap overview).
+
+    Rolls every matching elevator/delivery series up to a single average basis
+    first→last per crop, with how far it moved (positive = cash strengthened vs
+    futures). Use this for 'how is basis moving overall', optionally narrowed to
+    a crop and/or elevator. For the per-elevator breakdown use basis_detail."""
+    cm = commodity.strip().lower() if commodity else None
+    with track("basis_movement", commodity=cm, source=source, delivery=delivery, days=days):
+        if cm is not None and cm not in VALID_GRAIN:
+            return f"`commodity` must be one of {sorted(VALID_GRAIN)} (or omit for all grains)"
+        payload = client.history(commodity=cm, delivery=delivery, days=days)
+        return fmt.fmt_basis_movement(_filter_source(payload, source))
+
+
+@mcp.tool()
+def basis_detail(
+    commodity: Annotated[
+        str | None,
+        Field(description="Filter to one grain (corn / soy / wheat). Omit to span all grains."),
+    ] = None,
+    source: Annotated[
+        str | None,
+        Field(description="Filter to one elevator by exact display name. Omit for all."),
+    ] = None,
+    delivery: Annotated[
+        str | None,
+        Field(description="Filter to one delivery label (e.g. 'Jul 2026'). Omit for all."),
+    ] = None,
+    days: Annotated[
+        int, Field(ge=1, le=365, description="Lookback window in days.")
+    ] = 30,
+) -> str:
+    """Per-(elevator, crop, delivery) basis trend — the drill-down for basis_movement.
+
+    One compact row per series: basis first→last over the window and how far it
+    moved. All filters optional, so you can scope to one crop, one elevator, one
+    delivery, or any combination."""
+    cm = commodity.strip().lower() if commodity else None
+    with track("basis_detail", commodity=cm, source=source, delivery=delivery, days=days):
+        if cm is not None and cm not in VALID_GRAIN:
+            return f"`commodity` must be one of {sorted(VALID_GRAIN)} (or omit for all grains)"
+        payload = client.history(commodity=cm, delivery=delivery, days=days)
+        return fmt.fmt_basis_detail(_filter_source(payload, source))
 
 
 @mcp.tool()