Tooltips
Use the macro metadata element <help> in <block> or <parameter> to add tooltips for a custom Wires block or for individual properties in a custom block.
Tooltip text should be fairly short. It must be valid text for XML, so you must escape any XML delimiters, such as &.
<macros xmlns="http://www.open-mashup.org/schemas/v1.0/EMML"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.openmashup.org/schemas/v1.0/EMML/..
/schemas/EMMLPrestoSpec.xsd"
domain="myBlocks">
<macro name="helloWorld"
xmlns:presto="http://www.jackbe.com/v1.0/EMMLPrestoExtensions"
xmlns:macro="http://www.openmashup.org/schemas/v1.0/EMMLMacro">
<presto:macro-meta>
<block usage="Wires">
<label>Hello world!</label>
<help>Hello world block tooltip</help>
...
</block>
<parameters>
<parameter name="aString">
<label>Your name</label>
<help>Tooltip for this property</help>
</parameter>
...
</parameters>
</presto:macro-meta>
....
</macro>
...
</macros>