Exercise 2 — Solution

Task: The old R1 recovery rule and the modern @rules/ include
mechanism both solve the same underlying problem. Describe that
problem, and explain specifically what changed between the two
solutions in terms of what a human has to remember to do.

The underlying problem both solve: a brand-new Claude session starts
with no guaranteed memory of this project's own conventions, so
without some mechanism to reintroduce them, every session would have
to have its rules explained from scratch, or worse, would silently
proceed without them at all.

What changed between the two solutions:

Under the old R1 system, a human had to actively remember, at the
start of every single session, to paste a specific recovery prompt
("Please read the permanent_rules.md file stored in [path]...") before
any real work could safely begin. If that step was skipped - forgotten
in a rush, or simply not known by whoever was starting the session -
the rules were entirely absent for that session, with no automatic
fallback.

Under the current @rules/ system, the human's own remembering is
removed from the loop entirely for this specific purpose. CLAUDE.md
itself is read automatically at the start of every session in the
repository, and its own @rules/<filename> lines pull in every
referenced rules file's full content with no prompt needed at all.
The only thing a human still needs to remember is a genuinely
different, one-time task: when a NEW rules file is created, it has to
be added to that @rules/ list at least once (covered in Chapter 10) -
but from that point on, every future session picks it up automatically
with zero further action needed.

Notes:
- The chapter's own comparison table captures this exact shift in its
  "Trigger" and "What's still needed" rows - the manual step didn't
  disappear entirely, it moved from "every session" (R1) to "once, when
  a rules file is first created" (@rules/).
- This is a genuine reliability improvement, not just a convenience
  one - a single missed manual prompt used to mean an entire session
  ran with zero rules in effect, a much larger failure than forgetting
  to register one new file.