| name | usability-is-existence |
| description | Use when assessing feature completeness, auditing UX or onboarding, or judging whether a feature is "done" — especially gap analyses, SOTA comparisons, and first-run/cold-start reviews. |
Usability Is Existence
This skill defines a non-negotiable usability invariant:
A feature does not meaningfully exist unless at least one realistic interaction pathway allows a first-time user to discover and use it without prior knowledge.
This skill is authoritative and applies across UX, product, and implementation work.
Scope
This skill applies whenever an agent:
- Evaluates feature completeness
- Audits usability or UX
- Determines whether a feature “exists” or is “done”
- Performs gap analysis or SOTA comparison
- Assesses first-run or cold-start experiences
Core Rule (Invariant)
A feature MUST NOT be considered usable if:
- It can only be accessed via:
- Direct URLs
- Undocumented routes
- Internal knowledge
- Developer-only affordances
- It lacks any visible, inferable, or hinted UI entry point
- It requires prior awareness of its existence to be used
At least one valid pathway MUST:
- Start from visible UI elements
- Be reasonably discoverable by exploration
- Be achievable without reading documentation
- Be understandable in context
Consequences
If no such pathway exists:
- The feature is considered non-existent for users
- The feature MUST be flagged as:
- A UX defect
- An onboarding failure
- A discoverability gap
Technical existence alone is insufficient.
When NOT to Apply
- Internal/admin tooling deliberately URL- or permission-gated for a known audience
- APIs, CLIs, and SDKs — there, documentation IS the interaction pathway; judge doc discoverability instead
- Features explicitly scoped as hidden (feature-flagged betas, staged rollouts) — flag the gate, not the feature
Enforcement
If an agent claims a feature is “present” or “complete” without a valid user-discoverable pathway:
- The claim is invalid
- The agent MUST revise the assessment
- Downstream conclusions must not rely on the feature
Intent
This skill exists to prevent:
- “It’s there if you know where to click” products
- Hidden functionality masquerading as completeness
- Developer-centric definitions of usability
- Shipping features that only exist in theory
