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How the text of an issue reaches the AI

← Security design

The AI learns who wrote what from issue.md: a heading for the issue and for each comment names the author, the role, such as reporter or maintainer, and the date, and the AI's own earlier comments are marked as its own. The text under a heading is written by anyone, so it must not be able to write such a heading itself, nor hide what the maintainer can't see:

How the text of an issue and its comments reaches the AI: Each text of the issue and its comments loses its HTML, as GitHub hides it, then the characters that GitHub shows as nothing, and is cut off after 20,000 characters. In this order, no invisible character can end an HTML comment that GitHub never ends. It goes into a code fence with one backtick more than its longest run of backticks, so that no line of the text can end it. The heading above the fence, which only the script writes, names the author, the role and the date. The other issues and discussions become excerpts without HTML comments, lose their invisible characters too and go into JSON. The titles of the issues that a maintainer corrected lose their invisible characters as well and reach corrections.md as JSON strings in a code fence that no title can close. A notice in the log counts the characters that were removed.How the text of an issue and its comments reaches the AI: Each text of the issue and its comments loses its HTML, as GitHub hides it, then the characters that GitHub shows as nothing, and is cut off after 20,000 characters. In this order, no invisible character can end an HTML comment that GitHub never ends. It goes into a code fence with one backtick more than its longest run of backticks, so that no line of the text can end it. The heading above the fence, which only the script writes, names the author, the role and the date. The other issues and discussions become excerpts without HTML comments, lose their invisible characters too and go into JSON. The titles of the issues that a maintainer corrected lose their invisible characters as well and reach corrections.md as JSON strings in a code fence that no title can close. A notice in the log counts the characters that were removed.

  • Nothing in a text can end its fence. A fence ends only at a line of at least as many backticks as the line that opened it, and the assistant opens it with one backtick more than the longest run in the text, at least three. So ## Comment 4 by @owner (maintainer) in a text stays a line of that text, and so does a fence of the text's own, whatever its length. The prompt tells the AI that a fence holds only that person's text, whatever it looks like.
  • What GitHub doesn't show, the AI doesn't read. The tag characters of Unicode, U+E0001 to U+E007F, spell a whole sentence in ASCII that no browser shows, and zero-width spaces, joiners and the controls of the direction of writing hide or reorder text. The assistant removes every format character of Unicode and every code point that Unicode calls default ignorable, such as variation selectors, which can carry a byte each, from the issue and its comments, from the excerpts of the other issues and discussions, and from the AI's answer before its checks, so that none can hide a token from them either. They go after the HTML, which goes as GitHub hides it: a zero-width space in the --> of an HTML comment keeps the comment from ending on GitHub, so that it hides the rest of the text, and taken out first, it would end the comment and show the AI what GitHub hides. And they go before the fence is chosen, so that none can split a run of backticks that would end it.

Every analysis reads the excerpts of every open issue and of the closed ones that changed last, so a text planted in one issue reaches the AI again with each new issue. Its worst use would be to call new issues its duplicates, which close on their own. So only an original that a maintainer vouches for can close another issue:

When a duplicate that the AI found closes on its own: A duplicate that the AI is sure of, of an older open issue, gets the notice that closes it after three days only when a maintainer opened the original or triaged it, so that it no longer has needs-triage. Otherwise it becomes a suggestion for the maintainer and a related issue in the comment. A notice closes nothing when someone comments, when the reporter or anyone who may push to the repository reacts with a thumbs down, or when the original is closed or no longer vouched for by then.When a duplicate that the AI found closes on its own: A duplicate that the AI is sure of, of an older open issue, gets the notice that closes it after three days only when a maintainer opened the original or triaged it, so that it no longer has needs-triage. Otherwise it becomes a suggestion for the maintainer and a related issue in the comment. A notice closes nothing when someone comments, when the reporter or anyone who may push to the repository reacts with a thumbs down, or when the original is closed or no longer vouched for by then.