> For the complete documentation index, see [llms.txt](https://help.cubelet.ai/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://help.cubelet.ai/platform-and-integration/mcp-servers/scaffold-pjrc.md).

# Scaffold PJRC

*The gap-diagnostic MCP server and entry point of the learner journey.*

## Purpose

Scaffold is the PJRC gap diagnostic — PJRC stands for Pattern, Judgment, Relationship, Creative. It is the first stage of the learner journey: Scaffold (diagnose the gap) → Pursuit (mastery-paced training) → Passport (credential). Scaffold produces a learner's **Gap** profile — the delta between a learner's current mastery and the mastery a competency requires.

## Who it's for

Developers and AI agents building the entry point of the learner journey — anything that needs to diagnose a learner's gap before routing them into study (the Library) or practice (the Lab).

## Endpoint

`https://scaffold-mcp.euler-center.workers.dev/mcp`

## Tools

This reference does not enumerate Scaffold's individual tool names. Its documented role is producing a learner's Gap profile via the PJRC diagnostic — the surface that determines what a learner needs to study or practice next.

## Relationship to the manufacture server

Scaffold sits upstream of the manufacture server in the learner journey. The Gap profile it produces determines what a learner should study next: content study (the Library, via the manufacture server's cubelet content tools) and practice (the Lab) are both aimed at closing the gap Scaffold surfaced. Scaffold itself does not serve cubelet content — it diagnoses what's missing; the manufacture server (and, for CMMC or ISACA domains, their dedicated servers) is where that gap gets closed.