• Participant color encodes anything other than which person — urgency, evidence, status, approval, priority, or emphasis
• A Spectral State or Evidence State hue is used as a pattern role — chrome, participant, or interaction — anywhere in the archive
• Participant → role assignment is frequency-derived, so a refresh recolors a person
• The author is recolored, moved off the right, or assigned a participant role. A successor to an AA-compliant archive that deliberately adopts this template version and so takes default-ASK's author fill does not fail this item: that is an owner change, not a recoloring (pattern README, A successor to an AA-compliant archive)
• A legend or sender labels appear in data-party-mode="two-party"
• data-party-mode="two-party" contains more than two distinct participant IDs
• data-party-mode="two-party" contains any participant-a … participant-e message role — two-party is author + one frosted counterpart, nothing else
• data-party-mode="group" contains fewer than three distinct participants
• data-party-mode="group" renders without its legend, or without sender labels
• The group legend does not carry exactly one entry per distinct participant, including the frosted participant-default
• Invalid overflow or mis-moded messages are hidden or discarded in CSS instead of failing closed — party mode is a semantic contract, not a presentational filter

• The archive contains more than seven distinct participants (author + frosted default + a–e) and was rendered anyway instead of failing closed
• Participant colors are cycled or reused across different people
• One role is assigned to two or more people
• Overflow participants are silently collapsed into the frosted default role
• participant-f / -g / further roles have been invented without an owner-approved overflow contract
• A participant is dropped to fit the supported capacity

• A second template, duplicated message markup, duplicated script, a second flavor, or a flavor-specific branch exists
• In a render from this version, the root data-flavor attribute, or the manifest's flavor, is anything other than default-ASK — AA-compliant is retired, and a render from this version that carries its name overstates what it is. An archive sealed earlier keeps its recorded version, and a successor rendered from the earlier version its manifest records is checked against that version's checklist
• A successor to an AA-compliant archive is rendered from this version without recording the adopted version and each role's new bound value, or uses the adoption to recolor or remap anyone beyond the default-ASK values its existing roles take
• default-ASK has been "improved" toward AA — its lower-contrast metadata treatment is intentional
• The pattern-local participant values have been added to colors_and_type.css as general-purpose tokens
• A literal color value appears in the template that is not enumerated in the pattern README

• Any colour outside the closed palette plus this pattern's ratified participant ramp appears in pattern-owned presentation
• A global --fg-* / --line-* rebind appears (foreground must be inherited, not re-declared)
• Invented hex values appear in the archive's overlay CSS
• #201d26 is applied as a general default foreground rather than through this pattern's registered high-contrast roles
• --fg-high-contrast reaches a role outside the registered set: participant ink and search-highlight text on the sanctioned colored fills
• A use of --fg-high-contrast appears that is not registered in design-system-ASK, under High-contrast foreground — registered uses

• An attachment is dropped silently
• An attachment carries a state outside embedded · referenced · omitted-by-export · bytes-unavailable
• Provenance omits the media-fidelity profile, or omits counts for omitted / unavailable items
• The archive claims completeness it does not have

• A reaction exported as an ordinary message record without a deterministic source-recorded target relationship is dropped, or remodelled into reactions[] — the narrowly permitted transformation is the one the source itself supplies
• A target relation is inferred from quoted text, proximity, matching prose, or other heuristic evidence and presented as source truth
• The archive's message count changes merely to force reaction normalization
• The manifest omits the reaction representation mode or its counts
• A source that genuinely carries both representations is collapsed into one without disclosure

• A source-derived text node or attribute value is emitted unescaped
• Source payload is inserted through innerHTML
• Message text, participant labels, attachment filenames, channel labels, reactions, source pointers, or the precomputed data-s string are treated as trusted markup rather than untrusted data
• Linkification is added without escaping both label and URL, or without allowlisting protocols
• Any path exists by which source content becomes executable markup in the sealed archive

• The delivered archive is not self-contained: it requires the network, a sibling stylesheet, or a sidecar font
• An external <link> / @import / live raw-URL stylesheet reference survives into the delivered artifact
• A relative or external font URL resolving outside the artifact survives into the delivered artifact — inlining the token CSS alone does not seal the fonts
• The manifest omits the font-sealing mode, the canonical-font-files-carried answer, or the typography-guaranteed answer — the mechanical mode is inspectable in the bytes, but input-file provenance and a deliberate downgrade are not
• embedded-data-uri is claimed but a font payload is not self-contained, or its decoded data: bytes do not hash to the input SHA-256 recorded in Files copied into local mirror
• The font-sealing section restates input paths or hashes instead of referencing the canonical mirror table — one provenance record must not carry two editable copies of the same hash
• fallback-stacks is used but an @font-face block, or a broken font URL, survives into the delivered artifact
• fallback-stacks is used and the artifact or manifest claims canonical font bytes are embedded, or that exact typography is guaranteed — the downgrade is about what the artifact carries, so an archive that happens to render Inter on a machine with Inter installed is not a failure
• Search or year navigation fetches anything at runtime
• An unreplaced template marker ([placeholder], 0000000) appears in the delivered artifact

• The document omits <meta name="color-scheme" content="light dark">
• The live message count is not exposed as a status region (role="status" / aria-live)
• Two-party mode removes sender identity from the accessibility tree rather than only hiding it visually
• The author's messages carry no sender identification at all, visible or assistive
• The archive title is not a real heading element
• The visible reaction glyph or label falls below the applicable contrast threshold against its bubble fill — audit the rendered glyph, not only the chip container's computed color
• The reaction uses a forced emoji-presentation sequence (e.g. U+2764 U+FE0F), which paints a fixed colour and ignores currentColor; use a text-presentation glyph (U+2665 U+FE0E) or a textual label

• A theme is hard-coded on <html> / <body> without explicit reason
• The artifact does not honor prefers-color-scheme
• The participant ramp changes between light and dark (it is theme-invariant; only the author fill resolves per theme)

• A message bubble renders leading whitespace because the generator emitted a newline or indentation between the opening tag and the first child (.ma-m is white-space: pre-wrap)
• A message is missing data-pid, data-role, or data-s, so search or role binding breaks
• A merged-channel message is missing data-channel, losing its source provenance

• Inter is used for code, timestamps, or tabular metadata
• JetBrains Mono is used for prose message body
• Weights outside the approved set appear: Inter 200 / 300 / 400; JetBrains Mono 300 / 500
• 600 SemiBold or heavier appears
• Hierarchy is carried by opacity to the point that essential text becomes unreadable

• The artifact does not record a design-system-ASK source SHA
• A MANIFEST.md (or equivalent provenance record) is missing
• The manifest omits the flavor in use or the persistent participant → role mapping
• Live CSS is hot-linked from the upstream repo's raw URL or any live path
• A prior sealed archive was edited in place rather than superseded by a new render

• Private message content, real participant names, identifiers, or archive payload appear in any file committed to design-system-ASK
• The pattern's example content is anything other than generic, wall-safe placeholders

The accessibility-semantics items above are hard fails for every archive. The pattern makes no contrast-compliance claim beyond them: an archive that claims one is validated by its consumer, on the final rendered archive with its content, custom media and Tier 3 overlay applied.