Background Knowledge Demands

Evaluator last updated August 27, 2026.

Overview

The Background Knowledge Demands evaluator assesses the background knowledge complexity of reading passages:

Evaluates how much prior knowledge a text relies on
Lists key concepts in the text
Evaluates whether students have likely encountered these concepts before

At a glance


Supported grades	3–12
Rubric	Student Achievement Partners (SAP) ↗‘s Qualitative Text Complexity Rubric for Informational Text ↗ (Subject Matter Knowledge)
Model used	Gemini 3 Flash preview (`gemini-3-flash-preview`) with temperature of 0 The evaluator was built and validated using this specific model and temperature. Other configurations will produce different results and may have lower accuracy.

Getting started

Follow the Quickstart to start using this evaluator:

Access method
Evaluators playground	View in Platform ↗
SDK	TypeScript ↗
Other	Python notebook ↗ Prompts: `system.txt` ↗ and `user.txt` ↗

Inputs

Input	Description	Required
Text	Informational text to evaluate 10 - 10,000 words (< 1,200 words recommended)	Yes
Grade level	Target student grade level	Yes

Output

Field	Description
Complexity score	Slightly complex: Relies on everyday, practical knowledge; includes simple, concrete ideas Moderately complex: Relies on common practical knowledge and some discipline-specific content knowledge; includes a mix of simple and more complicated, abstract ideas Very complex: Relies on moderate levels of discipline-specific or theoretical knowledge; includes a mix of recognizable ideas and challenging abstract concepts Exceedingly complex: Relies on extensive levels of discipline-specific or theoretical knowledge; includes a range of challenging abstract concepts
Reasoning	Detailed synthesis of why the text fits the chosen complexity level
Identified topics	Core subjects and concepts found in the text
Curriculum check	Whether the topics are standard K-8 knowledge or specialized high-school-level knowledge
Assumptions and scaffolding	What the author assumes the reader already knows versus what is explained in the text
Friction analysis	Whether difficulty comes from vocabulary/sentence structure or from actual background knowledge demands

Interpreting results

Output	How to use
Complexity rating	Slightly complex: Confirm text relies on everyday knowledge students likely have Moderately complex: Plan light scaffolding for discipline-specific terms Very complex: Pre-teach key concepts before independent reading Exceedingly complex: Flag texts that assume extensive prior knowledge
Identified topics + Assumptions and scaffolding	Match text to what students have already encountered Example: Use identified topics, curriculum check, and friction analysis to decide what to pre-teach or explain in the text

Evaluator release history

Date	Changed
August 27, 2026	Minor prompt updates
March 13, 2026	First release

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Quickstart

Run an evaluator in the Evaluators playground, a Python notebook, or with the SDK.

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Overview

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Output

Interpreting results

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Text Complexity dataset

Quickstart

​Overview

​At a glance

​Getting started

​Inputs

​Output

​Interpreting results

​Evaluator release history

​Related topics

Text Complexity evaluators

Text Complexity dataset

Quickstart

Overview

At a glance

Getting started

Inputs

Output

Interpreting results

Evaluator release history

Related topics