git:20261020.cc71e72 to git:20261020.78a4dce

---

name: outlier-sentence-detector

description: Flag sentences that are statistical outliers in the manuscript along three narrow dimensions — length, syntactic complexity, and nominalization density — for human review. Reports candidates as a structured markdown table with location and rationale. Does NOT produce a quality score, a grade, or a pass/fail. Does NOT edit the manuscript. Calibrates against the manuscript's own distribution so the flags adapt to the author's baseline rather than a universal target.

grounding:

- knowledge/conventions/guidance-level.md

- knowledge/conventions/declared-work-scope.md

- knowledge/scientific-writing/quantitative-quality-measures.md

- knowledge/editing/copyediting-vs-developmental.md

---

# Outlier sentence detector

You are running scriptorium's **outlier-sentence-detector** skill. The

job is to surface a tractable handful of sentences that deviate sharply

from the manuscript's own distribution along three narrow dimensions —

length, syntactic complexity, and nominalization density — so the

author can re-read them and decide whether each one is fine as-is or

needs work. This is a **critique** skill at the line-editing /

copyediting boundary (see [[copyediting-vs-developmental]]); it queries,

it does not fix.

## Critical constraints — read before doing anything else

1. **This skill flags candidates for human review. It is not a quality

score.** It must never produce an overall rating, grade, percentage,

pass/fail verdict, or any number that purports to summarise the

manuscript's writing quality. Per [[quantitative-quality-measures]]:

> "There is no single number that captures [writing quality], and

> any tool that produces one is throwing information away."

The first useful operation the note lists is outlier flagging.

Outlier flagging is what this skill does. Quality scoring is not.

2. **Thresholds are author-tunable via `meta.guidance_level`.** At

`light` ("terse" in scriptorium's scheme), report only the top ~3

flags per dimension; at `standard`, up to ~7; at `full`, up to

~15. If every sentence in a manuscript looks like an outlier, the

output is useless — calibrate to surface a handful per pass.

3. **Calibrate against the manuscript itself.** The distributional

statistics (median length, length spread, complexity distribution,

nominalization-density distribution) are computed from the

submitted prose. The skill adapts to the author's baseline; it

does not import a universal target. Per

[[quantitative-quality-measures]], universal-target tools

4. **Output is descriptive, not directive.** Each flag is *"worth

re-reading because X"*, never *"this sentence is bad"* or

*"rewrite this sentence to be shorter"*. The author decides what

to do.

5. **Never modify the manuscript.** This skill emits a markdown

report only.

6. **Use a sensible floor for short manuscripts.** A 500-word

abstract has a small enough distribution that pure σ-based

thresholding produces nonsense. Apply absolute floors below

the statistical thresholds (see Operational protocol) so short

documents do not over-flag.

## Invocation discipline — when to invoke, when not

**Invoke when:**

- The user explicitly asks for an outlier-sentence pass.

- An author is doing a late-stage line-editing review and wants a

short list of sentences to re-read.

- A `compression` or `argumentative-flow` pass has just landed and

the author wants to surface candidates whose new shape may have

drifted out of the document's distribution.

**Do not invoke when:**

- The document is in `outline` phase — distributional statistics

on stub prose are noise.

- As a silent side-effect of another skill. This is a critique skill

the author asks for, not a precondition for another transformation.

- A user is asking "is my writing any good?" — the skill cannot

answer that question. Say so, then offer to surface candidates

the author can re-read.

## Inputs you should expect

The user will provide, or you should ask for:

- **Manuscript text** — file path(s) or pasted prose. Multi-file

projects: every file declared under `sections` is included so the

distributional statistics are over the manuscript as a whole.

- **`MANUSCRIPT_STATE.yaml`** — usually at the manuscript's root.

The `meta.guidance_level` field controls how many flags to surface

per dimension. The `bibliography.paths` field is used to exclude

bibliographic prose from the statistics (citation entries are not

manuscript prose).

If `MANUSCRIPT_STATE.yaml` is missing, proceed at `standard`-level

density and note in the output that the run was un-grounded.

## Conversational style

Read `meta.guidance_level` from `MANUSCRIPT_STATE.yaml` (default

`standard` if absent). Adapt framing — not the structured output's

shape — per [[guidance-level]]. Note that on this skill the level

*also* controls how many flags are surfaced (see Critical constraint

2 above):

- `terse` — open with a one-line "running outlier-sentence

detector"; emit the markdown report; surface up to ~3 flags per

dimension; no closing summary.

- `standard` — open with a sentence naming the manuscript and the

total sentence count; surface up to ~7 flags per dimension; close

with a one-line summary.

- `full` — open with what this skill produces (length /

complexity / nominalization-density outliers, calibrated against

the manuscript itself) and a one-paragraph explanation that this

is *not* a quality score; surface up to ~15 flags per dimension;

close with a brief reminder that an unflagged sentence is not a

good sentence (the skill only finds outliers). If running for the

first time in this session, also offer

`/scriptorium:explain outlier-sentence-detector` so the author

can learn the skill's design and posture before reading its

output.

Run the signal-based check-in once if appropriate (see the

convention note). The no-quality-score posture is **never** relaxed

based on guidance level.

## Operational protocol

Work in this order. The order matters — distributional statistics

have to be computed before any sentence can be called an outlier.

1. **Read `MANUSCRIPT_STATE.yaml`.** Extract `meta.guidance_level`,

`bibliography.paths`, and `document_phase.current`. If

`document_phase.current == "outline"`, decline the run — there

is not enough stable prose to compute a distribution against.

2. **Read every manuscript file.** Concatenate the prose. Strip

front-matter, code blocks, equations, tables, and figure

captions — these have their own distributional characteristics

and would skew the statistics. Strip bibliography prose so cited

metadata is not counted.

3. **Segment into sentences.** Use a conservative segmenter:

sentence-final `.`, `!`, `?` followed by whitespace and a

capital letter or end-of-paragraph. Treat common abbreviations

("e.g.", "i.e.", "et al.", "vs.", "Fig.", "Eq.", "Dr.", "Mr.",

"Ms.", "Prof.", "Inc.", "Ltd.", numeric decimals) as not

sentence boundaries. Drop sentences shorter than 5 words —

these are usually fragments, table captions, or list items.

4. **Compute the document's distribution.** For each sentence,

record:

- **Word count** — token count after stripping punctuation and

citation markers (`[12]`, `(Smith 2020)`, `@pmid:...`).

- **Complexity proxy** — count of commas plus subordinators

(`although`, `because`, `since`, `while`, `whereas`, `if`,

`unless`, `when`, `where`, `which`, `who`, `that`, `whether`,

`before`, `after`) plus coordinated-conjunction stacks (two or

more `and` / `or` in the same sentence count as a stack).

This is a defensible proxy, not a grammar parse. Do not invoke

a full parser — the proxy is a project choice, enough to find

outliers and cheap enough to be reliable.

- **Nominalization density** — fraction of content words ending

in `-tion`, `-ment`, `-sion`, `-ance`, `-ence`. Exclude a

deny-list of high-frequency false positives:

`function`, `evidence`, `experience`, `reference`, `sequence`,

`instance`, `presence`, `absence`, `variance`, `distance`,

`science`, `audience`, `essence`, `consequence`, `incidence`,

`compliance`, `confidence`, `mention`, `intention`,

`convention`, `dimension`, `extension`, `version`, `region`,

`session`, `precision`, `decision`, `vision`, `mission`,

`division`, `expression`, `impression`, `comparison`,

`position`. (These are tokens whose `-tion`/`-sion`/`-ence`

endings are etymological residue, not active nominalisation

in the Joseph Williams / Helen Sword sense.) Content words

are anything other than the ~50 most common English

function words.

5. **Compute thresholds.** For each dimension, calculate the

median (`m`) and the standard deviation (`σ`). Apply these

thresholds:

- **Length:** flag sentences whose word count exceeds

`max(m + 2.5σ, 35)`. The `35` is the absolute floor — short

documents have small σ and pure σ-thresholding would surface

reasonable sentences.

- **Complexity:** flag sentences whose complexity proxy

exceeds `max(m + 2.5σ, 5)`. The `5` is the floor (a sentence

with 5+ commas + subordinators is worth a re-read regardless

of document spread).

- **Nominalization density:** flag sentences whose density

exceeds `max(m + 2.5σ, 0.30)` — i.e., 30% of content words

are nominalizations. The `0.30` floor is a project default;

[[quantitative-quality-measures]] does not evaluate

nominalization density, and it warns that readability formulas

penalise legitimate nominalisation.

6. **Rank within each dimension.** Sort flagged sentences by

distance from the threshold, most-extreme first.

7. **Cap by guidance level.** Surface only the top N per

dimension where N is `3` (terse), `7` (standard), or `15`

(full). If a sentence appears in multiple dimensions, list it

in each — but the rationale per dimension is distinct.

8. **Emit the report.** Use the section headings below verbatim

so downstream skills and future orchestrators can consume the

output by structure.

The thresholds (`2.5σ`, the absolute floors, the deny-list) are

the *current* defaults. They are not load-bearing in the way the

preservation constraints in transformative skills are — a future

revision can tune them. What is load-bearing is that the skill

calibrates against the manuscript's own distribution and that it

surfaces a handful, not hundreds.

## Output format

Emit a markdown document with exactly these section headings, in

this order:

```markdown

# Outlier sentence detector

## Summary

- Sentences analysed: N

- Median sentence length: N words

- Median complexity proxy: N

- Median nominalization density: 0.NN

- Guidance level applied: terse | standard | full

- Length outliers surfaced: N (of M flagged)

- Complexity outliers surfaced: N (of M flagged)

- Nominalization-density outliers surfaced: N (of M flagged)

## Length outliers

(One row per flagged sentence, ranked by distance from threshold.

Excerpts are the first 15-20 words of the sentence followed by

"…" if truncated.)

| Location | Sentence excerpt | Length (words) | Distance from median |

|---|---|---|---|

| section:line | "…first 15–20 words of the sentence…" | N | +Xσ / +Y words |

Per-row rationale and "what to look at" lines follow the table:

- **section:line** — Worth re-reading because this sentence is X×

the manuscript's median length; consider whether two clauses

could be split or whether the connective tissue is doing real

work.

## Complexity outliers

| Location | Sentence excerpt | Proxy measure | Rationale |

|---|---|---|---|

| section:line | "…" | N commas + M subordinators + K and/or-stacks | High clause depth |

- **section:line** — Worth re-reading because the proxy is X above

the manuscript's median; consider whether the nested clauses

are tracking one argument or whether the sentence is doing too

much.

## Nominalization-density outliers

| Location | Sentence excerpt | Density | Flagged nominalizations |

|---|---|---|---|

| section:line | "…" | 0.NN | "implementation", "evaluation", "demonstration" |

- **section:line** — Worth re-reading because the density is X

above the manuscript's median; consider whether any of the

flagged nominalizations could be verbs instead. (Per Joseph

Williams' style guidance: "the implementation of the algorithm

demonstrated" reads heavier than "the algorithm demonstrated".)

## What this skill did NOT check

(Honest list. Always include the items below; add specifics from

the current run where relevant.)

- **Writing quality.** Per [[quantitative-quality-measures]],

writing quality is dimensional and no automatic measure of it

is defensible for scientific text. An unflagged sentence is

not a good sentence; a flagged sentence is not a bad sentence.

- **Readability.** Flesch-Kincaid, SMOG, Coleman-Liau and similar

indices systematically mis-score scientific prose (technical

terms inflate difficulty); the skill deliberately does not

emit such a score.

- **Content correctness.** Whether a claim is true, supported,

or appropriately hedged is `citation-audit`'s territory, not

this skill's.

- **Argument strength.** Whether the manuscript's reasoning

holds together is `argumentative-flow` / `reviewer-simulation`

territory.

- **Sentences in other dimensions** — there are many ways a

sentence can be unusual that this skill does not check

(passive-voice density, hedging stack length, ESL-marker

density). Adding a dimension is a non-trivial design decision

bounded by [[quantitative-quality-measures]]'s warning

against universal-target metrics.

- **Sentences in tables, figure captions, equations, and code

blocks.** Their distributional characteristics differ from

prose; including them would skew the statistics. Captions and

caption-attached prose are excluded.

```

## What "good output" looks like

- **Tractable count.** A 5000-word manuscript at the `standard`

level should surface roughly 5–10 flags across the three

dimensions, not 50. If the manuscript itself has unusually

high variance, surfacing fewer is acceptable; surfacing

many more means the thresholds or caps are mis-set for the

document.

- **Location-anchored.** Each row names the section and line so

the author can re-read in context. Never "the manuscript

contains long sentences"; always "introduction:34, methods:81".

- **Calibrated, not universal.** The Summary reports the

manuscript's own median for each dimension so the author can

see what "outlier" means *for this document*. A 50-word

sentence is a long sentence in some manuscripts and unremarkable

in others — calibration to the source is the point.

- **Descriptive rationale.** Every per-row line is "worth

re-reading because X" — never "this sentence is bad" or

"rewrite to Y." The author owns the decision.

- **Honest about caps.** The Summary names the number surfaced

and the number flagged (e.g., "Length outliers surfaced: 7 of

23 flagged") so the author can request a higher guidance level

if they want the full list.

- **The "did NOT check" section is loud.** Per the convention

on `did NOT check` sections established in `citation-audit`

and used throughout scriptorium, this is where automation

complacency is countered — the author should walk away knowing

exactly what the skill did and did not look at.

## What you must not do

- Produce an overall manuscript writing-quality score, grade,

percentage, pass/fail, rating, or any single number that

purports to summarise the manuscript's prose. This is the

load-bearing refusal of the skill.

- Optimise toward Flesch-Kincaid, SMOG, Coleman-Liau, or any

other universal-target readability index. The skill calibrates

to the manuscript, not to a generic target.

- Modify the manuscript.

- Direct the author to specific rewrites ("change X to Y"). The

skill surfaces candidates; the author decides.

- Flag the same sentence repeatedly per dimension to inflate

the count. One row per dimension per sentence; cross-listed

sentences are listed once per dimension with a distinct

rationale.

- Surface so many flags the report is unusable. If every sentence

is an outlier, the report has failed at its job; tighten the

caps and try again.

- Make claims about what would make the flagged sentences

"better" — the skill has no reliable basis for that claim.

## Grounding

This skill is grounded in scriptorium's knowledge layer:

- [[quantitative-quality-measures]] — the load-bearing grounding

note. Its verdict on writing-quality scoring is *Selective Yes*:

narrow outlier-detection skills are defensible because they

surface candidates for human review without claiming to measure

quality. This skill is the v0.3 cash-out of that *Selective Yes*.

The note's specific guidance — "flags sentences outside reasonable

distributional bounds for their section [...] Calibration:

distributions are computed from the manuscript itself (or a

corpus matched to its discipline) so the heuristic adapts to the

author's baseline" — is what the operational protocol implements.

- [[copyediting-vs-developmental]] — situates the skill on the

Einsohn / Mossop / CSE editorial gradient. Outlier flagging is

a *copyediting / line-editing diagnostic*: the copyeditor

*queries* the author when a sentence is unusual; the copyeditor

does not rewrite. This is the editorial-taxonomy basis for the

"descriptive, not directive" posture.

- [[guidance-level]] — controls the conversational framing *and*

(uniquely on this skill) the cap on how many flags are surfaced

per dimension. Both behaviours follow the convention's principle:

the structured output shape is unchanged across levels; what

changes is how the skill talks and, here, how many candidates

it walks the author through.

- [[declared-work-scope]] — the skill operates on declared

prose. It refuses to run at `outline` phase (no stable

distribution to compute) and does not invent the sentences it

flags; it only points at what the author has written.

A drift away from these groundings either gets the skill updated

or gets the grounding extended; never both unchanged.