v.buffer
v.buffer.distance - Creates a buffer around features of given type.
Vector (v.*)
QgsProcessingParameterVectorLayer|input|Input vector layer|-1|None|False
QgsProcessingParameterNumber|distance|Buffer distance in map units|QgsProcessingParameterNumber.Double|100.0|False|None|None
QgsProcessingParameterNumber|tolerance|Maximum distance between theoretical arc and polygon segments as multiple of buffer|QgsProcessingParameterNumber.Double|0.01|False|None|None
QgsProcessingParameterBoolean|-s|Make outside corners straight|False
QgsProcessingParameterBoolean|-c|Do not make caps at the ends of polylines|False
QgsProcessingParameterVectorDestination|output|Buffer