# Streamline Moderne — style guide for coding agents

> Generated from the Aesthetary record for **Streamline Moderne**.
> Research: **Partly sourced** · Build guidance: recorded in 7 of 8 research dimensions.
> 7 sources attached.

## How to use this

Paste this file into your agent as context before asking it to design or build something in this visual language. It states what is established, what is our interpretation, and what nobody has established. Treat all three differently.

**The most important section is "Not researched yet".** Its purpose is to stop you and your agent inventing rules that sound right and are not recorded anywhere.

## What this language is

**Defining:** Horizontal speed lines, rounded corners, curved forms, white stucco and metal trim

**Recognise it by:** Horizontal speed lines running in parallel across a form, corners rounded without exception, curved and continuous shapes rather than faceted ones, and bands of chrome or aluminium trim on smooth white or pale stucco. The diagnostic condition is horizontal continuity: the eye is pulled sideways along unbroken curves, and a stepped edge or a dominant vertical belongs to Art Deco. Art Deco steps and rises; Googie lifts diagonally and shouts at a motorist.

**Family:** Geometric & Graphic
**Era:** early-modernist
**Native medium:** architecture

**Scope:** Streamline Moderne is 1930s-40s American architecture and industrial design. Aesthetary translates its horizontal lines, round corners and nautical details to graphic surfaces; palette and type are our reading.

## What it is arguing

Everything should look as though it moves through air. Rounding every corner and running horizontal lines across a form borrows the logic of aerodynamics for objects that never travel, so modernity is expressed as motion at rest.

**It refuses:** Refuses the stepped vertical geometry and applied ornament of Art Deco, and refuses sharp corners.

## What it is not

Commonly confused with these. Getting the difference right matters more than getting the surface right:

- Googie
- Art Deco

## Established rules

Grouped by what kind of claim each is. A requirement of the language and our own interpretation are not interchangeable.

**How to read each rule.** Every rule states two separate things, and neither stands in for the other:

- **Kind of claim** (the heading): From our catalogue entry · Documented · Source not yet verified · Our reading · Documented · Source attached.
- **Evidence** (how it is established): Graded by our research brief · No source attached (`DOCUMENTED`) · From our catalogue entry (`SUPPORTED`) · Our reading (`CURATORIAL`) · Not researched yet (`UNKNOWN`) · No grade recorded (no grade in the record). Where a claim has its own canonical label, the Evidence line gives that label instead of the grade.
- **Product area**: which of the twelve areas the rule belongs to (Layout, Typography, Color, Imagery, Surface, Interface, Motion, Motif, Technique, Form, Hierarchy, Density), mapped from its raw area label in bold. "Context" means the rule is about the Aesthetic (its name, origin, lineage) rather than a part of the design. "Not mapped" means the raw area has no single area yet.
- The code in brackets is the `grade` field at `implementationConstraints.tokenRules.value.rules[].provenance.grade` in https://aesthetary.com/data/streamline-moderne.json. "From our catalogue entry" means: Stated in Aesthetary’s existing catalogue entry. An outside source is named only where one is linked to the claim.

### From our catalogue entry

_Carried over from Aesthetary's original catalogue entry. The reasoning behind it was never recorded._

- **layout** — Composition: horizontal speed lines; curved forms.
  - Kind of claim: From our catalogue entry · Evidence: From our catalogue entry · Product area: Layout
- **imagery** — Imagery: rendered chrome.
  - Kind of claim: From our catalogue entry · Evidence: From our catalogue entry · Product area: Imagery
- **form / motif / surface / technique** — Form/motif/surface/technique: rounded corners, curved forms.
  - Kind of claim: From our catalogue entry · Evidence: From our catalogue entry · Product area: not mapped

### Documented · Source not yet verified

- **form** — Expression is carried by the form itself; applied surface ornament is absent.
  - Kind of claim: Documented · Source not yet verified · Evidence: Documented · Source not yet verified · Product area: Form
- **form** — Horizontal continuity dominates: no vertical or stepped emphasis competes with the horizontal run of the form.
  - Kind of claim: Documented · Source not yet verified · Evidence: Documented · Source not yet verified · Product area: Form

### Our reading

- **hierarchy** — Rank by position along the horizontal run — leftmost on the speed line leads. Unusual and native.
  - Kind of claim: Our reading · Evidence: Our reading · Product area: Hierarchy
- **motion** — Horizontal travel at constant velocity. Nothing rises, nothing steps.
  - Kind of claim: Our reading · Evidence: Our reading · Product area: Motion

## Found in research

What research established from sources Aesthetary opened and checked. Each line names its area, how it is known, and where it is scoped. "Seen in the work" means the source documents particular works or products rather than the Aesthetic as a whole.

- **Typography** — Streamline Moderne storefront signs were typically built of individual letters, often in a sans-serif contemporary typeface.
  - Evidence: Documented · Source attached · Claim: `kcc:typography-1` · Covers storefront-specific character-defining features, San Francisco context statement.
- **Typography** — Walter Huxley was a proponent of the pared-back streamline style; his 1935 ATF typeface Huxley Vertical became one of the most popular ways to give printing this Deco flavour.
  - Evidence: Documented · Source attached · Claim: `kcc:typography-2` · Covers foundry naming and one designer; not a style-wide rule.
- **Color** — Walls are smooth stucco or concrete, often painted white.
  - Evidence: Documented · Source attached · Claim: `kcc:color-from-surface-1` · Covers San Francisco residential; WP adds 'subdued pastel'.
- **Surface** — Walls are smooth stucco or concrete, often painted white.
  - Evidence: Documented · Source attached · Claim: `kcc:surface-1` · Covers San Francisco residential; WP adds 'subdued pastel'.
- **Surface** — Industrial and new synthetic materials carry the look: chrome, Bakelite and other plastics, aluminium, stainless steel, glass block, tinted structural glass (Vitrolite, Carrara), porcelain enamel, plastic laminates.
  - Evidence: Documented · Source attached · Claim: `kcc:surface-2`
- **Surface** — Surfaces are sleek and gleaming: materials gave 'the appearance of newness and sleekness', and surfaces were polished to a gleaming finish.
  - Evidence: Documented · Source attached · Claim: `kcc:surface-3` · Covers S6 is a secondary architecture-media source.
- **Interface** — Radius is the style's defining edge treatment: rounded corners and curved surfaces, wraparound and curved glass, curved railings and overhangs.
  - Evidence: Documented · Source attached · Claim: `kcc:interface-1` · Covers architecture; translation to screen corner radius is Aesthetary's reading.
- **Interface** — Borders are metal bands and trim (aluminium, stainless steel, chrome) rather than ornamental frames.
  - Evidence: Documented · Source attached · Claim: `kcc:interface-2` · Covers door and window trim.
- **Interface** — A boxy variant without curves exists under the names Moderne or Art Moderne, so rounded radius distinguishes Streamline Moderne specifically.
  - Evidence: Documented · Source attached · Claim: `kcc:interface-3`
- **Motion** — Motion is represented, not performed: horizontal lines and rounded forms are described as creating 'the impression of motion and speed' in static buildings and objects.
  - Evidence: Documented · Source attached · Claim: `kcc:motion-1`
- **Motion** — Electric light was built into architectural structure in the style, but no opened source documents animated or moving light.
  - Evidence: Documented · Source attached · Claim: `kcc:motion-2`
- **Motif** — Speed lines (bands of horizontal piping or grooves) are a recurring mark on buildings, cars and small objects.
  - Evidence: Documented · Source attached · Claim: `kcc:motif-1`
- **Motif** — Nautical details recur: porthole windows, ship-like railings, curved glass; in France the style was called paquebot (ocean-liner style).
  - Evidence: Documented · Source attached · Claim: `kcc:motif-2` · Covers 'sometimes', per Getty.
- **Motif** — Applied historical ornament is generally absent; the repeating marks are the speed lines and nautical elements themselves.
  - Evidence: Documented · Source attached · Claim: `kcc:motif-3`
- **Technique** — The look depended on new building technologies, notably bending structural glass, and on newly developed materials (extruded aluminium, porcelain enamel, glass block).
  - Evidence: Documented · Source attached · Claim: `kcc:technique-1`
- **Technique** — Streamlining was based on admiration for industry and speed; contemporary criticism quoted by the Bard Graduate Center called it absurd to borrow forms from unrelated machinery, as with a pencil sharpener streamlined to resemble an airplane.
  - Evidence: Documented · Source attached · Claim: `kcc:technique-2` · Covers 1944 MoMA criticism quoted by BGC.
- **Technique** — Porcelain enamel facing was often laid in a squared pattern on storefronts.
  - Evidence: Documented · Source attached · Claim: `kcc:technique-3` · Covers storefronts.

## Positions by area

The overall position recorded for each area. "No overall position recorded" means rules exist for the area but no position above them; the rules still apply. It is not the same as "Not established", which means nobody has researched the area.

- **Layout** — Specified
- **Typography** — Specified
- **Color** — Specified
- **Imagery** — Specified
- **Surface** — Specified
- **Interface** — Specified
- **Motion** — Specified
- **Motif** — Specified
- **Technique** — Specified
- **Form** — Specified

## Design grammar — web primitives

A starting grammar for a website in Streamline Moderne: one horizontal run, every corner rounded, speed-line bands and thin metal trim on a pale ground, rank read from the left, and motion shown in the lines rather than performed.

Three kinds of line: **On the record** names a rule this record holds (its wording is under Established rules) and states what it becomes on the web. **Web translation** is Aesthetary's choice for the web, derived from the rules it cites; change it if you have a reason, keep the cited rule. **Not specified by the source** means the research reached this but the sources say nothing about it; **Not researched yet** means the research has not reached it yet. Either way, follow the instruction and do not invent a rule. Structured version: `designGrammar` in data/streamline-moderne.json.

### Colour

| Role | Value | Contrast | Use | Kind |
| --- | --- | --- | --- | --- |
| ground | `#F4EDDF` | — | The page: a pale, warm white standing for painted stucco. | Web translation |
| ink | `#232930` | 12.6:1 | Headings and body. | Web translation |
| petrol | `#155263` | 7.5:1 | The one accent: the lead capsule, links, focus. | Web translation |
| trim | `#5A646E` | 5.2:1 | Trim lines and small labels. | Web translation |
| chrome | `linear-gradient(180deg, #EDF1F3 0%, #B9C1C8 38%, #6E7883 62%, #99A2AB 100%)` | — | Speed-line bands only, drawn as a lit metal rod. Never text, never a fill behind text. | Web translation |

Other accents the record supports:

- Pure white ground (recorded as "often painted white"): `#FFFFFF`

- **On the record · Documented** · `claim:kcc:color-from-surface-1` → The ground is a smooth wall, often white.
- **On the record · Documented** · `claim:kcc:surface-2` → Chrome, aluminium and stainless steel are materials for trim and bands.
- **Web translation** — Use chrome as line work only, never as the palette. _Why:_ The research treats chrome as a material, so it draws the bands and edges and leaves the ground to the wall colour. (`claim:kcc:surface-2`, `claim:kcc:interface-2`)
- **Not specified by the source** — The sources do not specify a palette beyond the wall colour. _Instead:_ The ink and the one petrol accent are this page's choice; state any accent as yours.

### Typography

Family: a contemporary sans-serif, after the storefront letters the research documents. Stack: `"Jost SM", "Century Gothic", "Avenir Next", "Trebuchet MS", sans-serif`

| Role | Size | Weight | Line height | Case | Tracking | Measure | Setting | Use |
| --- | --- | --- | --- | --- | --- | --- | --- | --- |
| display | clamp(2rem, 5.6vw, 4.1rem) | 600 | 1.06 | uppercase | 0.12em | — | widened: scaleX(1.16) with the box compensated | The one name at the top. |
| plate | 0.82rem | 600 | 1.4 | uppercase | 0.26em | — | — | Section name plates seated on the course. |
| body | 1rem | 400 | 1.8 | not specified | 0.02em | 56ch | — | Sentences. |

- **On the record · Documented** · `claim:kcc:typography-1` → Storefront signs were built of individual letters, often in a contemporary sans-serif.
- **Web translation** — Set display type in a geometric sans in capitals, widened and tracked so the word runs sideways. _Why:_ A contemporary sans after the storefront letters, stretched to follow the horizontal run. (`claim:kcc:typography-1`, `token_rule:sm-r2`)
- **Web translation** — Keep headings at one size; rank comes from position, not scale. _Why:_ Rank by position along the run. (`token_rule:hierarchy-13`)
- **Not specified by the source** — The sources do not specify body type. _Instead:_ Any calm sans works for sentences; the widened capitals are for names and labels only.

### Grid and layout

A horizontal run, not a column grid: content hugs the left edge and later items step rightward, with full-width speed courses as the section dividers.

Tokens: step `clamp(1.25rem, 5vw, 4.5rem)` · course-gap `7px`

- **On the record · From our catalogue entry** · `token_rule:layout-3` → Composition is horizontal speed lines and curved forms.
- **On the record · Documented · Source not yet verified** · `token_rule:sm-r2` → Horizontal continuity dominates the form.
- **On the record · Our reading** · `token_rule:hierarchy-13` → Rank by position along the horizontal run: the leftmost leads.
- **Web translation** — Divide sections with a full-width band of three parallel lines, the middle one heavier. _Why:_ Speed lines are bands of horizontal piping or grooves; on a page they are the dividers. (`claim:kcc:motif-1`, `token_rule:layout-3`)
- **Web translation** — Step each later item one unit to the right instead of stacking it flush. _Why:_ Leftmost leads; what follows sits deeper along the run. (`token_rule:hierarchy-13`)
- **Not specified by the source** — Density is not specified by the source. _Instead:_ Leave open air to the right of the run; do not claim a density rule.

### Shape and geometry

Tokens: radius-capsule `999px` · radius-panel `1.6rem 1rem 1rem 1.6rem` · trim-width `1px` · band-heavy `6px` · band-light `3px`

- **On the record · Documented** · `claim:kcc:interface-1` → Radius is the defining edge: rounded corners and curved surfaces.
- **On the record · Documented** · `claim:kcc:interface-2` → Borders are metal bands and trim, not ornamental frames.
- **On the record · Documented** · `claim:kcc:interface-3` → A boxy variant exists under other names; the rounded radius is what marks this one.
- **On the record · Documented · Source not yet verified** · `token_rule:sm-r1` → Carry expression in the form; applied ornament is absent.
- **Web translation** — Round every corner on the page; no square box anywhere. _Why:_ Radius distinguishes the style from its boxy variant. (`claim:kcc:interface-1`, `claim:kcc:interface-3`)

### Imagery

- **On the record · From our catalogue entry** · `token_rule:imagery-7` → Imagery: rendered chrome.
- **On the record · Documented** · `claim:kcc:motif-2`, `claim:kcc:motif-3` → The repeating marks are speed lines and nautical details: portholes, ship-like railings, curved glass.
- **Web translation** — Draw chrome as a gradient on line work; do not place photographs of chrome as texture. _Why:_ Rendered chrome, used for the bands the research documents. (`token_rule:imagery-7`, `claim:kcc:surface-2`)
- **Not specified by the source** — The sources do not specify a photography or illustration style. _Instead:_ Use drawn marks from the documented set; do not add historical ornament to fill space.

### Components

Anatomy, tokens and states below are Web translation: Aesthetary's specification for the screen. Each value line after them says whether it restates a rule this record holds.

#### Button

A capsule on the run: fully rounded ends, a thin trim line, the leading action filled.

- Anatomy: 999px radius, both ends round; 1px trim line in steel; label in widened sans capitals; the lead action filled petrol
- Tokens: radius `999px` · border `1px solid #5A646E` · background `#F4EDDF` · lead-background `#155263` · lead-text `#F4EDDF` · height `44px`
- State, default: Pale ground, steel trim line, ink label.
- State, hover: Trim and label turn petrol.
- State, focus: 3px petrol outline, 3px off, following the capsule.
- State, active: Fills petrol; label turns to the ground colour.
- State, disabled: Dashed trim line, label in secondary ink.
- Accessibility: At least 44px tall.
- Accessibility: Label 7.5:1 on the filled capsule, 12.6:1 on the ground.
- Accessibility: Disabled is a dashed line, not only a fade.
- **Web translation** — Round both ends of every button fully. _Why:_ Rounded corners and curved surfaces are the style's defining edge; on screen the radius runs out to a capsule. (`claim:kcc:interface-1`)
- **Web translation** — Draw the edge as a thin metal line, not a shadow or a tinted box. _Why:_ Borders are metal bands and trim. (`claim:kcc:interface-2`)
- **Web translation** — Fill only the leading action; the others follow it to the right, outlined. _Why:_ Rank is a position along the run; fill marks the lead without making it bigger. (`token_rule:hierarchy-13`)

#### Card

A rounded panel with a trim line, its content leading from the left edge, never centred.

- Anatomy: trim line all round; radius larger at the leading (left) corners; title in widened capitals; one line of body
- Tokens: border `1px solid #5A646E` · radius `1.6rem 1rem 1rem 1.6rem` · padding `1.2rem` · background `#F4EDDF`
- State, default: Steel trim.
- State, hover: Trim turns petrol and doubles on the inside.
- State, focus: 3px petrol outline.
- Accessibility: The whole card is one link.
- Accessibility: Cards read left to right in source order, which is also their rank.
- **Web translation** — Round every corner, with the leading corners rounder than the trailing ones. _Why:_ The rounded, prow-like end reads forward; radius is the defining edge. (`claim:kcc:interface-1`)
- **Web translation** — Set cards in one horizontal run; the first on the left leads. _Why:_ Horizontal continuity dominates, and rank is a position along the run. (`token_rule:sm-r2`, `token_rule:hierarchy-13`)

#### Input

A capsule field with its label above it, ruled by the same trim line as the button.

- Anatomy: 999px radius; 1px steel trim; label above in small capitals; error as a sentence below
- Tokens: radius `999px` · border `1px solid #5A646E` · height `44px` · padding `0 1.2rem`
- State, default: Steel trim on the ground.
- State, focus: Petrol trim and a 3px petrol outline.
- State, error: Petrol double trim; the message begins "Error:".
- State, disabled: Dashed trim.
- Accessibility: The label is real text above the field.
- Accessibility: Errors are words, not colour alone.
- **Web translation** — Give fields the button's capsule and trim line. _Why:_ One edge treatment on every control: rounded, bordered by metal trim. (`claim:kcc:interface-1`, `claim:kcc:interface-2`)

#### Navigation

Capsule links seated on a three-line speed course; the current page is the filled one, and the order runs left to right.

- Anatomy: three parallel lines, the middle heavier, full width; capsule links riding the lines; current page filled petrol
- Tokens: course `3px / 6px / 3px, 7px apart` · radius `999px` · current `#155263`
- State, default: Outlined capsules on the course.
- State, hover: Trim and label turn petrol.
- State, focus: 3px petrol outline.
- State, current: Filled petrol, aria-current="page".
- Accessibility: aria-current marks the current page, not colour alone.
- Accessibility: The course is decoration, hidden from assistive technology.
- **Web translation** — Seat the navigation on a band of parallel horizontal lines. _Why:_ Speed lines, bands of horizontal piping or grooves, are the recurring mark; here they carry the menu. (`claim:kcc:motif-1`)
- **Web translation** — Order the links by importance from the left. _Why:_ Rank by position along the horizontal run. (`token_rule:hierarchy-13`)

### Motion

Durations, easing and the rest of this specification are Web translation: Aesthetary's choice for the screen.

- Durations: state 160ms, travel 19s
- Easing: state `linear`, travel `linear`
- Transforms: translateX only. Nothing rises, scales or rotates.
- Entrance: None. Content is there at load.
- Hover: Colour change on trim and label, linear, 160ms.
- Reduced motion: Everything holds still; a travelling element rests at its designed position.
- **Web translation** — Motion is represented, not performed: horizontal lines and rounded forms give the impression of speed. _Why:_ The cited rule belongs to the Aesthetic's own medium; applying it to a screen component or motion is our translation. (`claim:kcc:motion-1`)
- **Web translation** — If anything moves, it travels horizontally at constant velocity. Nothing rises, nothing steps. _Why:_ The cited rule belongs to the Aesthetic's own medium; applying it to a screen component or motion is our translation. (`token_rule:motion-14`)
- **Web translation** — Let at most one element travel, and only sideways. _Why:_ Motion is mostly drawn; one constant-velocity traveller is the page's whole budget. (`claim:kcc:motion-1`, `token_rule:motion-14`)
- **Not specified by the source** — Animated or moving light is not documented. _Instead:_ Do not animate glows or signs; the research found electric light built in, not moving.

### Deliberately not added

- **A palette beyond the wall colour** (color): The research gives white or pale stucco and metal trim; ink and accent are ours.
- **Body type** (typography): Only storefront lettering is documented.
- **Density** (gridLayout): Not specified by the source.
- **Photography or illustration style** (imagery): The record holds rendered chrome and the documented marks only.
- **Any interface convention of the period** (components): The subject is buildings and objects; all four components are translations.
- **Animated light** (motion): No opened source documents it.

## Coverage — what has been looked at

One row per research dimension a research pass considered. "Not researched yet" (`UNKNOWN`) means exactly that; a dimension can carry an Aesthetary recommendation and still be unresearched, and those are different things.

| Research dimension | Evidence | Resolved by | Carries a rule |
| --- | --- | --- | --- |
| Composition | Specified · From our catalogue entry | follows the recorded claim | yes |
| Typography | Specified | Aesthetary decided | yes |
| Hierarchy | Specified · Our reading | Aesthetary decided | yes |
| Colour | Specified · From our catalogue entry | follows the recorded claim | yes |
| Density | Not specified by the source | Aesthetary decided | no |
| Imagery | Specified · From our catalogue entry | follows the recorded claim | yes |
| Form/motif/surface/technique | Specified | follows the recorded claim | yes |
| Motion | Specified | Aesthetary decided | yes |

Unresearched: Typography, Motion. Where a rule appears for one of these it is Aesthetary's implementation recommendation, not a property of the language, and its Evidence line above says so.

## Not researched yet

Every area of this record has a recorded position. That is unusual — most records do not.

## Grade your own work

20 checks: 8 mechanically testable, 10 needing a person to look, 0 needing a source Aesthetary does not hold, 2 with no recorded position. 1 further research dimension produced no rule (Density). This rubric is silent on it. Scores do not add up. A failure against a required rule and a departure from something we invented are not the same result, and no total should let them cancel.

### Recognition — does this read as the intended Aesthetic?

- **[visual_human · recognition signature · Evidence: No grade recorded]** Strip every logo, word and borrowed image out of your work, then show it to someone who knows the collection. Do they land on this Aesthetic? The signature to hold is: Horizontal speed lines running in parallel across a form, corners rounded without exception, curved and continuous shapes rather than faceted ones, and bands of chrome or aluminium trim on smooth white or pale stucco. The diagnostic condition is horizontal continuity: the eye is pulled sideways along unbroken curves, and a stepped edge or a dominant vertical belongs to Art Deco. Art Deco steps and rises; Googie lifts diagonally and shouts at a motorist.
  - _If it fails:_ The work may be competent and still read as a different Aesthetic, or as none. Nothing below matters until this passes.

### Fidelity — are its defining rules present?

- **[unassessable · no recorded position · Evidence: Not researched yet (`UNKNOWN`)]** Nothing is recorded as a requirement of this Aesthetic. There is no rule here that your work must hold — which means nothing you do can fail this dimension, and nothing you do can satisfy it either. That is missing research, not freedom: our research brief does record failure modes to avoid, listed under avoidance below. They are recorded judgement, not requirements.
  - _If it fails:_ Not applicable. An empty dimension is an absence of research, never a pass and never a failure.

### Implementation — were those rules translated appropriately into this medium?

- **[visual_human · From our catalogue entry · Evidence: From our catalogue entry]** Your work may depart from this — but knowingly, not by accident. Composition: horizontal speed lines; curved forms.
  - _If it fails:_ A defensible departure, and you should be able to say why you made it.
- **[visual_human · Our reading · Evidence: Our reading]** Your work may depart from this — but knowingly, not by accident. Rank by position along the horizontal run — leftmost on the speed line leads. Unusual and native.
  - _If it fails:_ A defensible departure, and you should be able to say why you made it.
- **[visual_human · From our catalogue entry · Evidence: From our catalogue entry]** Your work may depart from this — but knowingly, not by accident. Imagery: rendered chrome.
  - _If it fails:_ A defensible departure, and you should be able to say why you made it.
- **[visual_human · From our catalogue entry · Evidence: From our catalogue entry]** Your work may depart from this — but knowingly, not by accident. Form/motif/surface/technique: rounded corners, curved forms.
  - _If it fails:_ A defensible departure, and you should be able to say why you made it.
- **[visual_human · Our reading · Evidence: Our reading]** Your work may depart from this — but knowingly, not by accident. Horizontal travel at constant velocity. Nothing rises, nothing steps.
  - _If it fails:_ Nothing. No one has researched the dimension yet, and this is only what Aesthetary would do. Departing from it costs you nothing.
- **[visual_human · Documented · Source not yet verified · Evidence: Documented · Source not yet verified]** Your work may depart from this — but knowingly, not by accident. Expression is carried by the form itself; applied surface ornament is absent.
  - _If it fails:_ A defensible departure, and you should be able to say why you made it.
- **[visual_human · Documented · Source not yet verified · Evidence: Documented · Source not yet verified]** Your work may depart from this — but knowingly, not by accident. Horizontal continuity dominates: no vertical or stepped emphasis competes with the horizontal run of the form.
  - _If it fails:_ A defensible departure, and you should be able to say why you made it.

### Avoidance — known failure modes, neighbour drift, cloning

- **[mechanical · recorded failure mode · Evidence: No grade recorded]** Check your work against this: No stepped or faceted geometry.
  - _If it fails:_ A failure mode recorded in our research brief: recorded judgement about what weakens this Aesthetic, not a requirement of the language.
- **[mechanical · recorded failure mode · Evidence: No grade recorded]** Check your work against this: No vertical emphasis.
  - _If it fails:_ A failure mode recorded in our research brief: recorded judgement about what weakens this Aesthetic, not a requirement of the language.
- **[mechanical · recorded failure mode · Evidence: No grade recorded]** Check your work against this: No sharp corners.
  - _If it fails:_ A failure mode recorded in our research brief: recorded judgement about what weakens this Aesthetic, not a requirement of the language.
- **[mechanical · recorded failure mode · Evidence: No grade recorded]** Check your work against this: No applied ornament.
  - _If it fails:_ A failure mode recorded in our research brief: recorded judgement about what weakens this Aesthetic, not a requirement of the language.
- **[mechanical · recorded failure mode · Evidence: No grade recorded]** Check your work against this: No diagonal lift.
  - _If it fails:_ A failure mode recorded in our research brief: recorded judgement about what weakens this Aesthetic, not a requirement of the language.
- **[visual_human · recorded failure mode · Evidence: No grade recorded]** Have you made any of these changes? Each one moves the work into a neighbouring Aesthetic: Against Art Deco: curved/horizontal versus stepped/vertical. Against Googie: horizontal speed versus diagonal lift. Anti-signature: a stepped setback or vertical emphasis returns it to Art Deco. An angled baseline makes it Googie.
  - _If it fails:_ You have built the neighbour. That may be fine — but name which Aesthetic you are in.
- **[mechanical · declared closure · Evidence: No grade recorded]** Check your work against this: Not open: steps.
  - _If it fails:_ This one is closed, not open. The record says generation must not go here.
- **[mechanical · declared closure · Evidence: No grade recorded]** Check your work against this: Not open: verticality.
  - _If it fails:_ This one is closed, not open. The record says generation must not go here.
- **[mechanical · declared closure · Evidence: No grade recorded]** Check your work against this: Not open: sharp corners..
  - _If it fails:_ This one is closed, not open. The record says generation must not go here.
- **[visual_human · neighbour drift · Evidence: No grade recorded]** Could your work be mistaken for Googie? That language is: Roadside American optimism; architectural signage translated to screen
  - _If it fails:_ Not necessarily wrong, but you are closer to Googie than to this Aesthetic.

### Accessibility — the Aesthetic preserved without its inaccessible practice

- **[unassessable · no recorded position · Evidence: Not researched yet (`UNKNOWN`)]** Does this Aesthetic conflict with any usability floor? Nobody has recorded one for it.
  - _If it fails:_ Nothing — and that is the problem. An unrecorded conflict is not an absent one. Hold AA on reading matter and decide the rest on other grounds.

**Not covered at all:** Density: Not specified by the source. These research dimensions produced no rule, so there is no check. Treat them as unscored, never as passed and never as failed.

## Rules for the agent

1. Do not invent rules for any area listed under **Not researched yet**.
2. Do not treat an absent position as permission to do anything you like — say that the language has no position, and decide on other grounds.
3. Keep our interpretations separable from the language's own requirements. If asked to justify a choice, cite which kind of claim it came from.
4. If you need something this record does not contain, say so rather than producing a confident answer from the aesthetic's name.
5. When you self-score against "Grade your own work", score only checks marked `mechanical`. Declare `visual_human` and `evidence_dependent` checks unjudged rather than guessing, and never score an `unassessable` one.
6. Evidence "Not researched yet" (`UNKNOWN`) is never a failure. It means nobody researched the dimension, so departing from what is written there costs nothing and must not be reported as a defect. "No grade recorded" is not a grade either: do not treat it as our decision or as an outside source.
7. In **Design grammar**, a "Web translation" line is our choice for the web and may be changed with a reason; the rules it cites may not. Never present a translation as a property of the language.

## Provenance

- Record: `streamline-moderne` · status `draft` · research `partly_researched`
- Full structured record: https://aesthetary.com/data/streamline-moderne.json
- Human-readable record: https://aesthetary.com/a/streamline-moderne.html
- This file is a snapshot. The record may have changed since; check the page above.

_Aesthetary is an alpha. Where a page says nothing, nobody has done the work yet._