Groundwork for the step's real change. The operator's decision is that the
floor is chosen and adjusted by the model using it, not shipped as a value
somebody has to defend:
"we need a model consistent surface for the adjustment of these floor values.
the user should be able to touch it but the model should be the thing
handling it 9 times out of 10."
A tuning surface cannot be consistent across six arms that each spell their
configuration differently, so the arms stop owning their numbers.
`retrieval_surfaces.SURFACES` names each one, its floor key and default, its
budget key and default, and — because they are rendered by the tuning tool and
the Settings UI — what it asks, over what corpus, and how often it fires. A
floor cannot be moved responsibly by anyone who does not know those three.
Three things fall out:
- **`k` becomes a real budget everywhere.** Only auto-inject had a configurable
one; `RULEHINT_LIMIT`, `PROMPTRULE_LIMIT` and `reply_preferences.LIMIT` were
constants. `k` is what binds under a low floor, so it has to be settable per
surface — and per surface is the point, since `pre_tool_rule` fires before
every Bash call while `prompt_rule` fires once a turn.
- **`write_path` gets its own budget, inherited not reset.** It shared
auto-inject's outright on the argument that "how many titles at once" means
the same thing on both. It does not, for the same reason. Unset, it still
reads auto-inject's key, so an install that tuned the shared knob does not
silently drop to a new default.
- **The duplicated read-and-clamp goes.** That shape is canon #2860 across 295
of 372 judged siblings. Survivable while the numbers were constants; not once
they are meant to move.
The long measurement comments stay exactly where they are — #2223's noise-floor
probe, #3853's command-vs-code split, #3851's band measurement. The constants
they annotate now alias the registry, so there is one value and the reasoning
still sits beside it.
Tests build the write-path config from the registry (`helpers.writepath_cfg`)
instead of from hand-written dicts. That is not tidiness: the rule arms read
their numbers inside a fail-open `except`, so a dict missing one key does not
raise where a reader would see it — the arm silently becomes a no-op that reads
exactly like "fired and found nothing". Ten hand-written dicts each looked
complete on the day they were typed.
tests/test_retrieval_surfaces.py pins the identity everything rests on: a
surface's name IS its telemetry source. Nothing in the type system says so —
`record_retrieval(source="pre_tool_rule")` is a literal in another file — and
renaming one without the other yields an arm that can be tuned and not
measured, or measured and not tuned, with no symptom either way.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01821k5B3Ysecp9fNYs92Kuy
bvandeusenandClaude Opus 5
09b48457ff