feat: 试用过程中的细节优化

server/services/prompts/common.py

@@ -134,11 +134,28 @@ def build_context(raw: dict, fallback_name: str = "", fallback_desc: str = "") -
                 break
 
     dimensions = raw.get("dimensions") or {}
-    dimension_values = (dimensions.get("length"), dimensions.get("width"), dimensions.get("height")) if isinstance(dimensions, dict) else ()
-    dimensions_line = ""
-    if len(dimension_values) == 3 and all(value is not None for value in dimension_values):
-        unit = dimensions.get("unit") or "mm"
-        dimensions_line = "L × W × H: " + " × ".join(str(value) for value in dimension_values) + f" {unit}"
+    known_dimensions: list[tuple[str, object]] = []
+    if isinstance(dimensions, dict):
+        known_dimensions = [
+            (label, dimensions[key]) for key, label in (("length", "length"), ("width", "width"), ("height", "height"))
+            if dimensions.get(key) is not None
+        ]
+    unit = (dimensions.get("unit") or "mm") if isinstance(dimensions, dict) else "mm"
+    dimensions_line = "; ".join(f"{label}: {value} {unit}" for label, value in known_dimensions)
+    known_labels = [label for label, _ in known_dimensions]
+    missing_labels = [label for label in ("length", "width", "height") if label not in known_labels]
+    dimension_annotation_instruction = (
+        "STRICT MEASUREMENT OUTPUT RULE: render exactly "
+        + str(len(known_labels))
+        + " measurement arrows and labels, only for: "
+        + ", ".join(known_labels)
+        + ". The only permitted dimension values are: "
+        + dimensions_line
+        + ". Do not infer product measurements. Do not draw, label, or show an arrow for: "
+        + ", ".join(missing_labels or ["any additional direction"])
+        + ", depth, thickness, diameter, or any other unlisted dimension."
+        if known_dimensions else ""
+    )
     params_line = "; ".join(
         f"{p.get('key')}: {p.get('value')}" for p in (raw.get("params") or [])[:8]
     )
@@ -158,6 +175,7 @@ def build_context(raw: dict, fallback_name: str = "", fallback_desc: str = "") -
             dimensions_line,
         ))),
         "price": raw.get("price") or "",
+        "dimension_annotation_instruction": dimension_annotation_instruction,
     }
 
 def selling_point_lines(ctx: dict, lang: str, max_n: int = 3) -> str: