You have built all three shapes - trees and themes over the documents, connections over the warehouse. The finale is the point of all of it: answering the questions you set out to answer back in Module 1.
Those questions do not fall to a single shape. This short lesson is the warm-up - Dani’s own question - where you see why, before the estate questions in the next challenge.
One shape is never the whole answer
Take Dani’s question: what fixed P0301 on cars like this? No single shape gets you there:
the documents name the candidates - the bulletins that mention the code, and the parts they call out (your trees and search tools)
the warehouse says which of those candidates actually held up - how often each was used, how often the car came back (the connections shape and the Text2SQL it grounds)
The agent reaches for both and the answer falls out: the parts the documents name, ranked by what the warehouse shows really worked.
mermaid
graph LR
Q((what fixed <br> P0301 on cars like this?)) --> D[documents shape:<br/>which bulletins name the code,<br/>and the parts they call out]
D -->|candidate parts| W[warehouse shape:<br/>how each part performed<br/>on similar vehicles]
W --> A((evidence-backed answer))
That read from Neo4j and BigQuery in the same pass - but that is just what reaching for two shapes looks like. The stores are an implementation detail; the answer is the point.
The connections shape keeps the warehouse half honest
The warehouse step is a multi-table join - work orders to vehicles to parts. Left to guess, Text2SQL is quietly wrong as the chain grows. The agent does not guess: it reads the foreign keys from the connections MCP you built in Module 2 and writes the SQL along the real join paths.
And nothing here is new plumbing - the documents are already a graph, the warehouse rows already stay in BigQuery (that was Module 2). The finale just puts the shapes to work together.
Summary
In this lesson, you saw the finale’s move - answering with more than one shape:
One shape is never the whole answer - Dani’s question needs the documents and the warehouse
Documents name the candidates; the warehouse says which held up - the agent reaches for both and the answer falls out
The connections shape keeps the warehouse query honest - the join paths from Module 2, not guesses
Touching both stores is a byproduct of reaching for both shapes - not the achievement
In the next challenge, you answer the estate questions, where the shapes cover and connect the whole set - not just one car.