This SKILL.md is the entrypoint for the Making Content Usable for People with Cognitive and Learning Disabilities (COGA) framework skill used by the Accessibility Planner and the Accessibility Skill Assessor subagent.
COGA is a Working Group Note published by the W3C Cognitive Accessibility Task Force. Unlike the normative WCAG 2.2 success criteria, COGA provides informative design guidance: 53 design patterns are organised into eight user-need objectives that together cover the accessibility needs of people with cognitive, learning, neurological, and age-related impairments. Each pattern describes a user need, suggested design approaches, and evaluation considerations. COGA patterns frequently complement WCAG 2.2 criteria, since several user needs (consistent navigation, clear labels, error prevention, focus support) are partially expressed across both standards.
Source: W3C, Making Content Usable for People with Cognitive and Learning Disabilities, https://www.w3.org/TR/coga-usable/.
Licensing posture
COGA is published under the W3C Document License as a Working Group Note. This skill paraphrases pattern intent rather than reproducing the source verbatim, in line with the paraphrase-preferred posture defined in accessibility-license-posture.instructions.md. Every per-objective reference file cites the canonical W3C URL anchor for each pattern, and any future verbatim quotation must carry the W3C copyright attribution line specified in that instruction file.
Pattern roll-up
The table below lists every COGA pattern grouped by objective. The Reference column links into the per-objective reference file using an anchor that matches the section header for that pattern. Total: 53 patterns across 8 objectives.
| # | Pattern | User need | Design patterns | Assessment heuristics | Reference |
|---|---|---|---|---|---|
| 1.1 | Make the Purpose of Your Page Clear | Clear Purpose | Descriptive titles, headers, signposts, top-of-page summary | Confirm purpose is visible without scrolling; titles match the task | objective-clear-purpose.md#control-make-the-purpose-of-your-page-clear |
| 1.2 | Use a Familiar Hierarchy and Design | Clear Operation | Conventional layout, predictable patterns, standard navigation | Confirm controls live where users expect; avoid novel patterns | objective-clear-purpose.md#control-use-a-familiar-hierarchy-and-design |
| 1.3 | Use a Consistent Visual Design | Clear Operation | Consistent layout, colours, typography, control placement | Confirm same controls render identically across pages | objective-clear-purpose.md#control-use-a-consistent-visual-design |
| 1.4 | Make Each Step Clear | Clear Operation | One concept per step, step indicators, progress feedback | Confirm each step has a clear heading and progress is visible | objective-clear-purpose.md#control-make-each-step-clear |
| 1.5 | Clearly Identify Controls and Their Use | Clear Operation | Conventional control shapes, visible focus, descriptive labels | Confirm interactive elements look interactive; labels describe outcome | objective-clear-purpose.md#control-clearly-identify-controls-and-their-use |
| 1.6 | Make the Relationship Clear Between Controls and the Content They Affect | Clear Operation | Proximity, grouping, visible references, aria-controls |
Confirm users can predict what a control will change | objective-clear-purpose.md#control-make-the-relationship-clear-between-controls-and-the-content-they-affect |
| 1.7 | Use Icons that Help the User | Use Symbols | Familiar icons, paired text labels, consistent meaning | Confirm icons have text labels and follow industry conventions | objective-clear-purpose.md#control-use-icons-that-help-the-user |
| 2.1 | Make it Easy to Find the Most Important Tasks and Features of the Site | Findability | Prominent placement, above-the-fold key actions, clear entry points | Confirm primary tasks appear without scrolling on common viewports | objective-find-help.md#control-make-it-easy-to-find-the-most-important-tasks-and-features-of-the-site |
| 2.2 | Make the Site Hierarchy Easy to Understand and Navigate | Findability | Logical groupings, predictable menus, breadcrumbs | Confirm sitemap depth is shallow; navigation paths are stable | objective-find-help.md#control-make-the-site-hierarchy-easy-to-understand-and-navigate |
| 2.3 | Use a Clear and Understandable Page Structure | Findability | Distinct page regions, headings, whitespace, dividers | Confirm regions are visually distinct and use landmark roles | objective-find-help.md#control-use-a-clear-and-understandable-page-structure |
| 2.4 | Make it Easy to Find the Most Important Actions and Information on the Page | Findability | Prominent CTAs, summary at top, key info above the fold | Confirm primary actions are visually emphasised and reachable quickly | objective-find-help.md#control-make-it-easy-to-find-the-most-important-actions-and-information-on-the-page |
| 2.5 | Break Media into Chunks | Findability | Segmented video, chapter markers, summaries | Confirm long media has chapter navigation or transcripts with anchors | objective-find-help.md#control-break-media-into-chunks |
| 2.6 | Provide Search | Findability | Site search, spell-check, suggestions, recent queries | Confirm search exists and tolerates typos and synonyms | objective-find-help.md#control-provide-search |
| 3.1 | Use Clear and Understandable Language | Clear Meaning | Plain language, defined terms, simple vocabulary | Confirm reading level matches audience; jargon is defined inline | objective-clear-meaning.md#control-use-clear-and-understandable-language |
| 3.2 | Use Familiar Words | Clear Meaning | Common words, audience-appropriate vocabulary | Confirm uncommon words have a glossary entry or definition | objective-clear-meaning.md#control-use-familiar-words |
| 3.3 | Use Simple Sentence Structure | Clear Meaning | Short sentences, active voice, one idea per sentence | Confirm sentences are short and avoid embedded clauses | objective-clear-meaning.md#control-use-simple-sentence-structure |
| 3.4 | Use Headings and Sections | Clear Meaning | Hierarchical headings, scannable sections | Confirm headings are nested correctly and convey topic | objective-clear-meaning.md#control-use-headings-and-sections |
| 3.5 | Use Lists | Clear Meaning | Bulleted or numbered lists, short list items | Confirm enumerable content is presented as a list rather than prose | objective-clear-meaning.md#control-use-lists |
| 3.6 | Keep Text Succinct | Clear Meaning | Short paragraphs, summaries, removal of filler | Confirm content is trimmed to essentials; long pages have summaries | objective-clear-meaning.md#control-keep-text-succinct |
| 3.7 | Use Clear, Unambiguous Formatting and Punctuation | Clear Meaning | Standard punctuation, avoid all-caps, avoid italics for emphasis | Confirm formatting is consistent and avoids cognitive ambiguity | objective-clear-meaning.md#control-use-clear-unambiguous-formatting-and-punctuation |
| 3.8 | Separate Each Instruction | Clear Meaning | One instruction per line, numbered steps, clear separation | Confirm multi-step tasks are split into discrete numbered steps | objective-clear-meaning.md#control-separate-each-instruction |
| 3.9 | Use White Spacing | Clear Meaning | Generous margins, line height, spacing between blocks | Confirm density is low enough that elements do not crowd each other | objective-clear-meaning.md#control-use-white-spacing |
| 3.10 | Ensure Foreground Content is not Obscured by Background | Clear Meaning | High contrast, no busy backgrounds behind text | Confirm text contrast meets WCAG and backgrounds do not interfere | objective-clear-meaning.md#control-ensure-foreground-content-is-not-obscured-by-background |
| 3.11 | Explain Implied Content | Clear Meaning | Spell out idioms, expand abbreviations, define references | Confirm content does not assume cultural or contextual knowledge | objective-clear-meaning.md#control-explain-implied-content |
| 3.12 | Provide Alternatives for Numerical Concepts | Clear Meaning | Visualisations, comparisons, plain-language equivalents | Confirm numbers and percentages have non-numeric alternatives | objective-clear-meaning.md#control-provide-alternatives-for-numerical-concepts |
| 3.13 | Support Different Modalities | Clear Meaning | Text, image, audio, video alternatives | Confirm critical content is reachable via at least two modalities | objective-clear-meaning.md#control-support-different-modalities |
| 4.1 | Ensure Controls and Content Do Not Move Unexpectedly | Error Prevention | Stable layouts, no auto-shifts, predictable insertions | Confirm targets remain stable while users interact with the page | objective-error-prevention-recovery.md#control-ensure-controls-and-content-do-not-move-unexpectedly |
| 4.2 | Let Users Go Back | Error Prevention | Back button works, undo for actions, no trap pages | Confirm browser back and explicit back navigation always work | objective-error-prevention-recovery.md#control-let-users-go-back |
| 4.3 | Notify Users of Fees and Charges at the Start of a Task | Error Prevention | Upfront pricing disclosure, hidden-fee avoidance | Confirm all costs are disclosed before any commitment is made | objective-error-prevention-recovery.md#control-notify-users-of-fees-and-charges-at-the-start-of-a-task |
| 4.4 | Design Forms to Prevent Mistakes | Error Prevention | Minimal fields, clear labels, format examples, inline validation | Confirm forms reduce required input and validate as users type | objective-error-prevention-recovery.md#control-design-forms-to-prevent-mistakes |
| 4.5 | Make it Easy to Undo Form Errors | Error Prevention | Saved drafts, retained input on error, undo affordances | Confirm partial form data persists after a validation failure | objective-error-prevention-recovery.md#control-make-it-easy-to-undo-form-errors |
| 4.6 | Use Clear Visible Labels | Error Prevention | Persistent visible labels, no placeholder-only labels | Confirm labels remain visible after the user types | objective-error-prevention-recovery.md#control-use-clear-visible-labels |
| 4.7 | Use Clear Step-by-step Instructions | Error Prevention | Numbered steps, one action per step, examples | Confirm multi-step flows have explicit step indicators and examples | objective-error-prevention-recovery.md#control-use-clear-step-by-step-instructions |
| 4.8 | Accept Different Input Formats | Error Prevention | Flexible date, phone, address parsing | Confirm common input formats are accepted without strict masks | objective-error-prevention-recovery.md#control-accept-different-input-formats |
| 4.9 | Avoid Data Loss and Timeouts | Error Prevention | No arbitrary timeouts, autosave, timeout warnings | Confirm no required rapid response; timeouts are warned and extendable | objective-error-prevention-recovery.md#control-avoid-data-loss-and-timeouts |
| 4.10 | Provide Feedback | Error Prevention | Confirmation messages, status updates, undo prompts | Confirm every user action produces visible or audible feedback | objective-error-prevention-recovery.md#control-provide-feedback |
| 4.11 | Help the User Stay Safe | Error Prevention | Warnings before risky actions, confirmation prompts | Confirm destructive or costly actions require confirmation and are reversible | objective-error-prevention-recovery.md#control-help-the-user-stay-safe |
| 4.12 | Use Familiar Metrics and Units | Error Prevention | Locale-appropriate units, conversions, plain labels | Confirm units match user locale or provide conversions | objective-error-prevention-recovery.md#control-use-familiar-metrics-and-units |
| 5.1 | Help Users Focus | Focus | Minimise distractions, prioritise one task at a time | Confirm pages do not present competing concurrent demands on attention | objective-supports-attention.md#control-help-users-focus |
| 5.2 | Make Short Critical Paths | Focus | Few steps to complete core tasks, streamlined flows | Confirm primary tasks complete in the smallest practical number of steps | objective-supports-attention.md#control-make-short-critical-paths |
| 5.3 | Avoid Too Much Content | Focus | Limit on-screen items, three to six functions, brief content | Confirm visible content is bounded and avoids dense paragraphs | objective-supports-attention.md#control-avoid-too-much-content |
| 6.1 | Ensure Processes Do Not Rely on Memory | Memory | Persistent information, repeated context across steps | Confirm users do not need to recall data from prior screens | objective-minimise-memory-load.md#control-ensure-processes-do-not-rely-on-memory |
| 6.2 | Let Users Avoid Navigating Voice Menus | Memory | Text alternative to voice IVR, skip-prompts, quick keys | Confirm voice or phone flows have text equivalents or shortcuts | objective-minimise-memory-load.md#control-let-users-avoid-navigating-voice-menus |
| 6.3 | Do Not Rely on User Calculations or Memorising Information | Memory | Provide calculated values, avoid memorisation for security | Confirm calculations are done for the user; auth does not require recall puzzles | objective-minimise-memory-load.md#control-do-not-rely-on-user-calculations-or-memorising-information |
| 7.1 | Clearly State the Results and Disadvantages of Actions, Options, and Selections | Help | Outcome descriptions, warnings about consequences | Confirm each choice explains what it does and what changes | objective-feedback-confirmation.md#control-clearly-state-the-results-and-disadvantages-of-actions-options-and-selections |
| 7.2 | Provide Help for Forms and Non-standard Controls | Help | Inline help, examples, password rules, control-specific docs | Confirm complex inputs have inline accessible help | objective-feedback-confirmation.md#control-provide-help-for-forms-and-non-standard-controls |
| 7.3 | Make It Easy to Find Help and Give Feedback | Help | Persistent help link, multiple support channels | Confirm help is reachable from every page and offers multiple channels | objective-feedback-confirmation.md#control-make-it-easy-to-find-help-and-give-feedback |
| 7.4 | Provide Help with Directions | Help | Step-by-step guidance, wayfinding, tooltips | Confirm tasks include clear contextual directions and visual aids | objective-feedback-confirmation.md#control-provide-help-with-directions |
| 7.5 | Provide Reminders | Help | Reminders for recurring tasks, confirmation of important actions | Confirm scheduled or repeated tasks support reminder hooks | objective-feedback-confirmation.md#control-provide-reminders |
| 8.1 | Let Users Control When the Content Moves or Changes | Adapt | User-initiated motion, pause controls, no auto-launching pop-ups | Confirm animation and auto-rotation have user-accessible controls | objective-user-control.md#control-let-users-control-when-the-content-moves-or-changes |
| 8.2 | Enable APIs and Extensions | Adapt | Compatible with assistive add-ons, password managers, simplifiers | Confirm pages do not block accessibility-enhancing browser extensions | objective-user-control.md#control-enable-apis-and-extensions |
| 8.3 | Support Simplification | Adapt | Simplified-view toggle, three to six core functions in simplified mode | Confirm a low-complexity alternative view is available where practical | objective-user-control.md#control-support-simplification |
| 8.4 | Support a Personalised and Familiar Interface | Adapt | Customisable layout, colours, terminology, system-preference respect | Confirm user preferences are honoured and persisted across visits | objective-user-control.md#control-support-a-personalised-and-familiar-interface |
Assessment heuristics
Per-pattern assessment heuristics, design pattern detail, and scope notes live inside the per-objective reference files in references/. The Accessibility Skill Assessor subagent consumes the appropriate objective-<slug>.md#control-<pattern-slug> section when evaluating a finding against a specific COGA pattern.
Cross-skill use is the common case: a COGA finding usually cites both the pattern reference here and the most closely related WCAG 2.2 success criterion in wcag-22. For example, a page that auto-rotates a carousel without a pause control is cited against objective-user-control.md#control-let-users-control-when-the-content-moves-or-changes (for the COGA user-control pattern) and ../wcag-22/references/guideline-2-2.md#sc-2-2-2 (for the WCAG 2.2.2 Pause, Stop, Hide requirement).
Skill layout
SKILL.md— this file (skill entrypoint and 53-row roll-up table).references/— one markdown file per COGA objective. Each file contains a paraphrased description of every pattern within the objective, aDesign patternslist of implementation approaches, anAssessment heuristicslist for evaluation, and a canonical W3C source URL anchor.