Specification for Trusted PLs?

Folks,

I feel dumb.

I have been looking for a document which specifies what trusted and
untrusted PLs must do and forbid, so far without result.

Where do we document this, and if we don't where *should* we document
this?

Cheers,
David.
-- 
David Fetter <david@fetter.org> http://fetter.org/
Phone: +1 415 235 3778  AIM: dfetter666  Yahoo!: dfetter
Skype: davidfetter      XMPP: david.fetter@gmail.com
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