Rubric / Readability
Content without JavaScript
content.js_required_for_primary_content
weight 2heuristic
Primary content is visible without JavaScript.
Definition
Check ID
content.js_required_for_primary_content
Category
Readability
Weight
2
Counts toward the score
Yes.
Evaluated by
A fixed rule whose threshold AgentSpeed chose. Reproducible; another rubric may reasonably disagree.
Chosen parameter
detector = no-JS visibility heuristic
Standard maturity
established
Canonical spec
None. This check has no published external specification — it is an AgentSpeed rule.
Introduced in
r2026.04.1
Retired in
Still active.
History
Every change to the instrument— including the versions that changed this check
Machine-readable
/rubric.json— this check, and every other, as data
How often this check is right
No rate published. Too few labelled cases to publish a rate: 1 flagged case (30 needed to publish), 1 defective case (30 needed to publish). The counts are the honest answer here. The matrix behind content.js_required_for_primary_content is 2 labelled cases — reported here rather than turned into a percentage that would read as more certain than the evidence is.
Corpus v1, measured under rubric r2026.11.0. Full method and every other check at /rubric/accuracy.
How to fix it
Render your primary headings, body copy, and calls-to-action in server HTML. Many agents fetch without executing JS. If you must hydrate, include the core content in the initial HTML response.
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