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FabledScribe/src/scribe/services/retrieval_telemetry.py
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feat(telemetry): tell a ranker decline from a repeat before the observation window opens (#3497)
Making the rule arms log every call exposed a second ambiguity in the same
row. `result_count == 0` is two unrelated events wearing one number:

  - the ranker found nothing above the bar — the only evidence a threshold is
    set too high; and
  - the ranker found only what this session had already been shown — which
    says nothing whatever about the bar.

A long session excludes its way into the second, so the arm reads worse the
longer it runs correctly. Rows written now carry the ambiguity permanently,
which is why this lands before any watch period rather than after.

`retrieval_logs.suppressed_count` (0095, nullable) holds what the caller
dropped as already-shown. Both rule arms report it; they filter in Python and
always know. The note arms pass exclusions INTO semantic_search_notes and
never see what was dropped, so they store NULL.

THE NULL IS LOAD-BEARING. It means "not measured here", and the readout
renders it as `suppression: null` rather than a zeroed dict. Defaulting to 0
would let an unmeasured surface read as a perfectly clean one — the same
substitution of an artifact for a measurement that #3311 made. No backfill,
for the same reason: existing rows genuinely do not know.

`retrieval_telemetry`'s `sources` gains `suppression` with `measured_calls`,
`calls_with_suppression` and `zero_because_already_shown`; subtract the last
from `zero_result_calls` for the true ranker declines. The MCP tool docstring
says to read the two together and warns against reading the null as a zero.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_011cPyzNnegXHr5iRMzzy5KJ
2026-09-03 21:12:38 -04:00

658 lines
30 KiB
Python

"""Retrieval telemetry — one RetrievalLog row per semantic-retrieval call.
This is the empirical basis for KB-injection tuning: it records what each query
asked for, the score distribution of what came back, and the effective params,
so the similarity threshold and top-k can be tuned from data rather than guessed.
Design notes:
- Fire-and-forget, mirroring upsert_note_embedding: `record_retrieval` extracts
the primitives it needs SYNCHRONOUSLY (while the caller's Note objects are
still valid) and schedules the DB insert as a background task, so logging
never adds latency to — or can break — the search response.
- Result objects are reduced to {id, score, rank} before scheduling; the
background writer touches only plain data, never a possibly-detached ORM row.
- Every failure path is swallowed: telemetry must never take down retrieval.
"""
from __future__ import annotations
import asyncio
import logging
from typing import Any
from datetime import datetime, timedelta, timezone
from sqlalchemy import case, func, select
from scribe.models import async_session
from scribe.models.base import iso
from scribe.models.note import Note
from scribe.models.note_usage import PULLED, SURFACED, NoteUsageEvent
from scribe.models.rule_usage import PULLED as RULE_PULLED
from scribe.models.rule_usage import SURFACED as RULE_SURFACED
from scribe.models.rule_usage import RuleUsageEvent
from scribe.services.rule_usage import is_ambient
from scribe.models.retrieval_log import RetrievalLog
logger = logging.getLogger(__name__)
# Strong references to in-flight inserts — the loop holds tasks only weakly,
# and an unreferenced fire-and-forget task can be collected before it runs
# (same guard as note_usage, found via #2663).
_pending: set[asyncio.Task] = set()
# Whether this process already dropped its one warning about failing writes.
_reported = False
def _build_payload(
*,
user_id: int | None,
source: str,
query: str | None,
threshold: float | None,
limit: int | None,
project_id: int | None,
is_task: bool | None,
results: list[tuple[float, Note]],
duration_ms: float | None,
suppressed: int | None = None,
) -> dict:
"""Reduce a retrieval call to a flat, JSON-safe RetrievalLog payload.
Pure and synchronous (no DB, no event loop) so it is unit-testable and safe
to run inline before scheduling the write. `results` is the
`(score, Note)` list from semantic_search_notes, already highest-first.
`suppressed` is how many scored hits the caller dropped because the session
had already been shown them, and it stays None for callers that cannot
know. See the column's comment: None means "not measured here", which is a
different fact from 0 and must never render as one.
"""
items = [
{"id": int(note.id), "score": round(float(score), 5), "rank": rank}
for rank, (score, note) in enumerate(results)
]
scores = [it["score"] for it in items]
return {
"user_id": user_id,
"source": source,
"query": query,
"threshold": threshold,
"limit_n": limit,
"project_id": project_id,
"is_task": is_task,
"result_count": len(items),
"suppressed_count": (None if suppressed is None else int(suppressed)),
"top_score": (scores[0] if scores else None),
"min_score": (scores[-1] if scores else None),
"result_ids": items,
"duration_ms": (round(duration_ms, 2) if duration_ms is not None else None),
}
async def _insert_retrieval_log(payload: dict) -> None:
"""Persist one RetrievalLog row. Best-effort: failures degrade, visibly.
WARNING rather than debug — this table is the empirical basis for threshold
tuning, and a silent write outage yields a dataset that looks complete while
covering only part of the traffic (#2663's shape). Once per process is
enough to be found; per-call would flood the log with what it already said.
"""
global _reported
try:
async with async_session() as session:
session.add(RetrievalLog(**payload))
await session.commit()
except Exception:
if not _reported:
_reported = True
logger.warning("retrieval telemetry write failed", exc_info=True)
else:
logger.debug("retrieval telemetry write skipped", exc_info=True)
def record_retrieval(
*,
user_id: int | None,
source: str,
query: str | None,
threshold: float | None,
limit: int | None,
project_id: int | None,
is_task: bool | None,
results: list[tuple[float, Any]],
duration_ms: float | None = None,
suppressed: int | None = None,
) -> None:
"""Fire-and-forget: record one retrieval call.
`results` needs only `.id` on each record, which is why it is not typed to
Note: rules are retrieved too (milestone 307) and land here rather than in
note_usage_events. That table's ids are REMAPPED on a backup restore, so a
rule id written into it would come back attached to whatever note happened
to take that number — silent corruption of the very evidence this exists to
provide. retrieval_logs is not restored at all, so it has no such hazard,
and `source` already distinguishes the surfaces.
Builds the payload inline (synchronously) then schedules the insert so the
caller returns immediately. Never raises — telemetry must not affect search.
"""
try:
payload = _build_payload(
user_id=user_id,
source=source,
query=query,
threshold=threshold,
limit=limit,
project_id=project_id,
is_task=is_task,
results=results,
duration_ms=duration_ms,
suppressed=suppressed,
)
except Exception:
logger.debug("retrieval telemetry payload build failed", exc_info=True)
return
try:
task = asyncio.get_running_loop().create_task(_insert_retrieval_log(payload))
except RuntimeError:
# No running loop (e.g. called from sync context outside the app) —
# skip rather than block. The app paths always run on the loop.
logger.debug("retrieval telemetry skipped — no running event loop")
return
_pending.add(task)
task.add_done_callback(_pending.discard)
# --- The read half (#2975) ---------------------------------------------------
# Until this existed, `retrieval_logs` was WRITE-ONLY: rows accrued and the only
# `select()` over them in the whole tree lived in a test. That made #1038's gate
# — "build the reranker once telemetry shows precision is the bottleneck" —
# unsatisfiable by construction, and it is why the one real tuning decision on
# record (the 0.68 write-path threshold, #2223) was reached by hand-probing the
# live instance with eight payloads instead of by reading what was collected.
def _bucket(rows: list) -> dict:
"""A score readout a human can act on, from one aggregate row."""
(calls, zero, cleared, p10, p50, p90, lo, hi, avg_n, dur,
measured, supp_calls, supp_zero) = rows
return {
"calls": int(calls or 0),
# A call that returned nothing is not a low-scoring call — it is a
# different failure (nothing indexed, filter too narrow), and averaging
# it into the score distribution would hide both.
"zero_result_calls": int(zero or 0),
# How often the best hit actually cleared the threshold in force for
# that call. THE precision-adjacent number: a surface that clears its
# bar on almost every call is either well-tuned or too loose, and the
# score spread below says which.
"cleared_threshold": int(cleared or 0),
# Of the zeros above, which were the RANKER declining and which were
# the reader having seen it already? `zero_result_calls` cannot say,
# and only the first kind is evidence about the threshold.
#
# None — not a zeroed dict — when no row in the window reported it. A
# surface that filters inside the search genuinely does not know, and
# rendering that as `{"calls": 0}` would state a measurement nobody
# made. That substitution is the whole of #3311.
"suppression": (
None if not int(measured or 0) else {
"measured_calls": int(measured or 0),
"calls_with_suppression": int(supp_calls or 0),
# Subtract from zero_result_calls for the true ranker declines.
"zero_because_already_shown": int(supp_zero or 0),
}
),
"top_score": {
"p10": _round(p10), "p50": _round(p50), "p90": _round(p90),
"min": _round(lo), "max": _round(hi),
},
"avg_result_count": _round(avg_n),
"p90_duration_ms": _round(dur, 1),
}
def _round(v, places: int = 4):
return None if v is None else round(float(v), places)
async def retrieval_summary(user_id: int | None, *, days: int = 30) -> dict:
"""What the retrieval telemetry says, per surface, over a window.
Three aggregates side by side, each read from the table built for it — NOT
a join. `usage` is notes, `rule_usage` is rules, and they stay apart
because a few dozen eligible rules blended into thousands of notes is the
note ratio with noise on it (milestone 333). `NoteUsageEvent`'s own docstring is explicit that the two are
complements ("RetrievalLog tunes the threshold, this tunes the corpus") and
that RetrievalLog's JSONB `result_ids` "can't be indexed at" the per-note
grain. So the score distribution comes from `retrieval_logs` on its indexed
columns, and surfaced-vs-pulled comes from `note_usage_events` at the grain
it was built for. Reading each from its own table is both cheaper and more
honest than correlating them through JSONB.
`usage["by_source"]` is the one join, and it stays INSIDE
`note_usage_events` — surfaced rows against pulled rows on note_id. That
answers "of the notes this surface chose, how many were opened", which the
top-level ratio averages away. It does not cross into `retrieval_logs`, so
the sentence above still holds.
Scoped to one user's own telemetry. There is no sharing model for a
retrieval log — it records what THIS user's agent asked for, including the
query text — so an owner filter is the whole access rule here rather than a
shortcut around `services/access.py` (P#78 governs shared record kinds).
Never raises: a telemetry readout that can break its caller is worse than
no readout. It does distinguish "no rows" from "the read failed", because
#2663 is exactly the bug where those two looked identical for weeks.
"""
since = datetime.now(timezone.utc) - timedelta(days=max(1, int(days)))
out: dict = {
"window_days": int(days),
"since": iso(since),
"sources": {},
"usage": {},
"rule_usage": {},
"read_failed": False,
}
cleared = case(
(
(RetrievalLog.threshold.isnot(None))
& (RetrievalLog.top_score.isnot(None))
& (RetrievalLog.top_score >= RetrievalLog.threshold),
1,
),
else_=0,
)
zero = case((RetrievalLog.result_count == 0, 1), else_=0)
# Three sums rather than one, because "not measured" and "measured as zero"
# are different answers and a single counter cannot hold both.
measured = case((RetrievalLog.suppressed_count.isnot(None), 1), else_=0)
supp_calls = case((RetrievalLog.suppressed_count > 0, 1), else_=0)
supp_zero = case(
((RetrievalLog.result_count == 0) & (RetrievalLog.suppressed_count > 0), 1),
else_=0,
)
def pct(p: float):
return func.percentile_cont(p).within_group(RetrievalLog.top_score.asc())
# Assigned inside the try below; named here so the readout can tell
# "this query failed" from "this window has no rows" (#2663).
by_source_rows = None
rule_rows = None
distinct_rules_surfaced = distinct_rules_pulled = 0
try:
async with async_session() as session:
rows = (
await session.execute(
select(
RetrievalLog.source,
func.count().label("calls"),
func.sum(zero).label("zero"),
func.sum(cleared).label("cleared"),
pct(0.1), pct(0.5), pct(0.9),
func.min(RetrievalLog.top_score),
func.max(RetrievalLog.top_score),
func.avg(RetrievalLog.result_count),
func.percentile_cont(0.9).within_group(
RetrievalLog.duration_ms.asc()
),
func.sum(measured).label("measured"),
func.sum(supp_calls).label("supp_calls"),
func.sum(supp_zero).label("supp_zero"),
)
.where(
RetrievalLog.created_at >= since,
RetrievalLog.user_id == user_id,
)
.group_by(RetrievalLog.source)
)
).all()
for row in rows:
out["sources"][row[0]] = _bucket(list(row[1:]))
# The corpus side, at its own grain. `ambient` mirrors
# note_usage.usage_for_notes: an ambient surfacing was not a scored
# CHOICE, so folding it into pull-through would understate it.
# Grouped by RAW source, then classified in Python. The
# alternative — CASE expressions in the GROUP BY — is the shape
# that produced #2663: a second case() renders its own expanding
# bind names, the database sees two different expressions and
# rejects the query, and the broad except swallows it. One CASE is
# provably fine (usage_for_notes does it); two is where it broke.
# `source` has a handful of distinct values, so grouping on it
# directly is cheap and cannot fail that way at all.
urows = (
await session.execute(
select(
NoteUsageEvent.event,
NoteUsageEvent.source,
func.count().label("n"),
)
.where(
NoteUsageEvent.created_at >= since,
NoteUsageEvent.user_id == user_id,
)
.group_by(NoteUsageEvent.event, NoteUsageEvent.source)
)
).all()
# Distinct-note counts need their OWN queries, and this is not
# fussiness: count(distinct note_id) per (event, source) group
# cannot be summed across groups — a note surfaced by two sources
# is one distinct note and would be counted twice. A wrong number
# labelled "distinct" is worse than no number.
from scribe.services.note_usage import AMBIENT_SOURCES as _AMB
distinct_surfaced = (
await session.execute(
select(func.count(func.distinct(NoteUsageEvent.note_id))).where(
NoteUsageEvent.created_at >= since,
NoteUsageEvent.user_id == user_id,
NoteUsageEvent.event == SURFACED,
NoteUsageEvent.source.notin_(_AMB),
)
)
).scalar_one()
distinct_pulled = (
await session.execute(
select(func.count(func.distinct(NoteUsageEvent.note_id))).where(
NoteUsageEvent.created_at >= since,
NoteUsageEvent.user_id == user_id,
NoteUsageEvent.event == PULLED,
)
)
).scalar_one()
# Per-source pull-through, at the NOTE grain (#3311).
#
# The `urows` query above already groups by source and the loop
# below then throws the source away, so until now this readout
# could say what the corpus's overall pull-through was and nothing
# about WHICH surface earned it. The data was always here; only
# the aggregation discarded it.
#
# It cannot be had by grouping the PULLED rows by source: a pull
# records the door it came through (`mcp_get_note`), not the
# surface that put the record in front of the agent. Correlating
# those within a session is what #2085 ruled out — there is no
# session identity server-side and inventing one would mean
# threading a client-supplied token through every read path. The
# note grain answers the question without one: of the distinct
# notes surface X chose, how many did an agent open in this window?
#
# Guarded separately from the reads above, on #2663's actual
# lesson. That outage was a NOVEL SQL SHAPE the database rejected
# inside a broad except. This join is the novel shape here, and a
# failure in it must not take down two readouts that already work.
try:
pulled_ids = (
select(NoteUsageEvent.note_id)
.where(
NoteUsageEvent.created_at >= since,
NoteUsageEvent.user_id == user_id,
NoteUsageEvent.event == PULLED,
# autoescape because `_` is a LIKE wildcard: a bare
# like("mcp_%") also matches "mcpX…". The Python half
# of this readout uses str.startswith and has no such
# hazard; this is the SQL half's version of it.
NoteUsageEvent.source.startswith("mcp_", autoescape=True),
)
.distinct()
.subquery()
)
surfaced_pairs = (
select(NoteUsageEvent.source, NoteUsageEvent.note_id)
.where(
NoteUsageEvent.created_at >= since,
NoteUsageEvent.user_id == user_id,
NoteUsageEvent.event == SURFACED,
)
.distinct()
.subquery()
)
# DISTINCT on (source, note_id) FIRST, which is what lets the
# outer aggregate be a plain count(): the pairs are already
# unique, so the left join cannot multiply them and no
# count(DISTINCT) is needed to undo damage that never happens.
by_source_rows = (
await session.execute(
select(
surfaced_pairs.c.source,
func.count().label("notes_surfaced"),
func.count(pulled_ids.c.note_id).label("notes_pulled"),
)
.select_from(
surfaced_pairs.outerjoin(
pulled_ids,
pulled_ids.c.note_id == surfaced_pairs.c.note_id,
)
)
.group_by(surfaced_pairs.c.source)
)
).all()
except Exception:
logger.warning("per-source pull-through read failed", exc_info=True)
by_source_rows = None
# Rules, at their own grain and in their own block (milestone 333).
#
# Guarded separately from the reads above for the reason `by_source`
# is: this table is NEW, and an instance running upgraded code
# against un-migrated schema would otherwise take down two readouts
# that work perfectly in order to report a third that cannot.
#
# The queries themselves are the note block's shapes, not novel
# ones — a group-by on two indexed columns and two count(distinct).
# The distinct counts need their own queries for the same reason
# the note ones do: count(distinct rule_id) per group cannot be
# summed across groups without double-counting a rule two sources
# both touched.
try:
rule_rows = (
await session.execute(
select(
RuleUsageEvent.event,
RuleUsageEvent.source,
func.count().label("n"),
)
.where(
RuleUsageEvent.created_at >= since,
RuleUsageEvent.user_id == user_id,
)
.group_by(RuleUsageEvent.event, RuleUsageEvent.source)
)
).all()
# The rows carry `source`, so the ranked/ambient split is done
# below rather than in SQL — the bulk surfaces started emitting
# on 2026-09-03 (#3473), so there IS an ambient class now.
#
# `distinct_rules_surfaced` deliberately counts BOTH classes. It
# answers "how many distinct rules did this install put in front
# of an agent at all", which is the denominator for dead weight
# — and a rule delivered by the preload a hundred times and
# never opened is the most important case that question has.
distinct_rules_surfaced = (
await session.execute(
select(func.count(func.distinct(RuleUsageEvent.rule_id)))
.where(
RuleUsageEvent.created_at >= since,
RuleUsageEvent.user_id == user_id,
RuleUsageEvent.event == RULE_SURFACED,
)
)
).scalar_one()
distinct_rules_pulled = (
await session.execute(
select(func.count(func.distinct(RuleUsageEvent.rule_id)))
.where(
RuleUsageEvent.created_at >= since,
RuleUsageEvent.user_id == user_id,
RuleUsageEvent.event == RULE_PULLED,
)
)
).scalar_one()
except Exception:
logger.warning("rule usage read failed", exc_info=True)
rule_rows = None
distinct_rules_surfaced = distinct_rules_pulled = 0
except Exception:
logger.warning("retrieval summary read failed", exc_info=True)
out["read_failed"] = True
return out
from scribe.services.note_usage import AMBIENT_SOURCES
usage = {
"surfaced": 0, "ambient": 0,
"pulled": 0, "pulled_by_agent": 0, "pulled_by_human": 0,
"distinct_notes_surfaced": int(distinct_surfaced or 0),
"distinct_notes_pulled": int(distinct_pulled or 0),
}
for event, source, n in urows:
n = int(n)
if event == SURFACED:
if source in AMBIENT_SOURCES:
usage["ambient"] += n
else:
usage["surfaced"] += n
elif event == PULLED:
usage["pulled"] += n
# The mcp_/rest_ split is load-bearing (see NoteUsageEvent's own
# comment, which names #1038 — this readout's whole purpose). "Is
# this record dead weight?" is answered by ANY pull; "was that
# injected line useful to the agent?" only by an AGENT pull. So
# pull-through, which exists to answer the second, counts mcp_*
# only. Both halves are reported so the first question is still
# answerable from the same payload.
if source.startswith("mcp_"):
usage["pulled_by_agent"] += n
else:
usage["pulled_by_human"] += n
# Ranked surfacings in the denominator, agent pulls in the numerator: the
# "surfaced often, opened never" reading is only valid where a scored
# surface CHOSE the record and an agent was the one who declined it.
usage["pull_through"] = (
round(usage["pulled_by_agent"] / usage["surfaced"], 4)
if usage["surfaced"] else None
)
# The same question, per surface — which is the one the top-level ratio
# cannot answer. A corpus average of 0.05 is compatible with one surface
# earning its noise and another producing none, and tuning a threshold
# needs to know which.
#
# UPPER BOUND, and say so where it will be read: a pull records the door,
# not the surface that led to it, so a note surfaced by two surfaces and
# opened once counts as pulled for both. Attribution would need the session
# identity #2085 declined to invent. The bound is still decisive in the
# direction that matters — a surface reading near zero here is not being
# flattered by the double-count.
if by_source_rows is None:
usage["by_source"] = {}
# Distinct from an empty window, for the same reason `read_failed` is.
usage["by_source_failed"] = True
else:
by_source: dict[str, dict] = {}
for source, n_surfaced, n_pulled in by_source_rows:
n_surfaced, n_pulled = int(n_surfaced or 0), int(n_pulled or 0)
ambient = source in AMBIENT_SOURCES
by_source[source] = {
"notes_surfaced": n_surfaced,
"notes_pulled": n_pulled,
# None rather than a number on an ambient surface: nothing
# CHOSE those records, so "surfaced often, opened never" is not
# a judgment about them. The counts stay visible; the ratio
# that would be misread does not.
"pull_through": (
None if ambient or not n_surfaced
else round(n_pulled / n_surfaced, 4)
),
"ambient": ambient,
}
usage["by_source"] = by_source
out["usage"] = usage
# ── Rules, deliberately a SEPARATE block ────────────────────────────
#
# Not folded into `usage`, for two reasons and the second is the one that
# bites. The corpora differ by orders of magnitude — a few dozen eligible
# rules against thousands of notes — so one blended ratio would be the note
# ratio with a little noise on it, and the rule arm's own behaviour would
# be undetectable inside it. And `usage` is what existing callers already
# read: silently changing what it counts would move a number people have
# been comparing across windows, without telling them it now measures
# something else.
#
# `ambient` now carries the bulk deliveries — the SessionStart preload,
# `list_always_on_rules`, and every `rules_payload` surface (#3473). Before
# they emitted, this block had no ambient key and said the absence was a
# fact about the data. It was, and it was also the thing that made the
# always-on set impossible to judge: the largest rule surface in the
# product was the one surface its own scoreboard could not see.
#
# READ THE TWO SEPARATELY, ALWAYS. `surfaced` is a claim a ranker made and
# a pull can settle. `ambient` is a delivery nobody chose, so a high count
# says the set is large and resident, never that it is useful.
rule_usage = {
"surfaced": 0, "ambient": 0,
"pulled": 0, "pulled_by_agent": 0, "pulled_by_human": 0,
"distinct_rules_surfaced": int(distinct_rules_surfaced or 0),
"distinct_rules_pulled": int(distinct_rules_pulled or 0),
}
if rule_rows is None:
# The FLAG is added, the shape is kept — matching `by_source_failed`
# one block up. A caller that renders this must not have to choose
# between crashing on a missing key and quietly showing zeros it has no
# right to: the keys let it render, and the flag tells it the zeros are
# "we could not find out" rather than "nothing happened" (#2663).
rule_usage["rule_usage_failed"] = True
else:
for event, source, n in rule_rows:
n = int(n)
if event == RULE_SURFACED:
# One definition of ranked-vs-ambient, imported rather than
# restated — the per-rule badge readout reads the same
# predicate, and two spellings of "what counts as surfaced" is
# precisely the uneven wiring #3246 found across this system.
if is_ambient(source):
rule_usage["ambient"] += n
else:
rule_usage["surfaced"] += n
elif event == RULE_PULLED:
rule_usage["pulled"] += n
# Same split, and it carries MORE weight here than for notes.
# The arm's whole claim is "this rule may apply to what you are
# writing", and only an agent opening it says the claim landed.
# A person browsing the rule list says nothing about the hint.
if source.startswith("mcp_"):
rule_usage["pulled_by_agent"] += n
else:
rule_usage["pulled_by_human"] += n
# None, not 0.0, when nothing was surfaced — matching the note block. A
# ratio of zero asserts "we showed rules and none were opened"; with an
# empty numerator AND denominator that is a claim the data does not
# support, and it is the reading that would make a brand-new install look
# like a broken one.
#
# RANKED SURFACINGS ONLY in the denominator, and this is the load-bearing
# line of the whole change. Pull-through asks "was that hint any use", and
# only a surface that CHOSE what it showed can be judged by it. Folding the
# preload in would divide the same pulls by a number that grows with every
# session and every rule added to the resident set — so enlarging the
# always-on set would DEPRESS the arm's measured precision, and trimming it
# would flatter it, neither for any reason to do with the arm. The ambient
# count sits beside it, unaveraged, and is read as size rather than skill.
rule_usage["pull_through"] = (
round(rule_usage["pulled_by_agent"] / rule_usage["surfaced"], 4)
if rule_usage["surfaced"] else None
)
out["rule_usage"] = rule_usage
return out