+### Attributes added during parsing
+
+⛩️📰 书社 will add a few attributes to the output of the parsing step,
+ namely :—
+
+- A `@书社:cksum` attribute on toplevel result elements, giving the
+ `cksum` checksum of the corresponding source file.
+
+- For the elements which result from parsing plaintext `<html:script>`
+ elements :—
+
+ - A `@书社:parsed-by` attribute, giving a space‐separated list of
+ parsers which parsed the node.
+ (Generally, this will be a list of one, but it is possible for the
+ result of a parse to be another plaintext node, which may be
+ parsed by a different parser.)
+
+ - A `@书社:media-type` attribute, giving the identified media type of
+ the plaintext node.
+