01 Structure
Who may trade, on what venue, under what rule. Exchanges, dealers, dark pools, RFQ. Why the same name prints two different prices.
02 Liquidity
The ability to transfer risk without moving the world. Depth, tightness, immediacy, resilience. Capacity is a market fact, not a wish.
03 Risk
What can be lost before the thesis is discussed. Market, liquidity, credit, operational. Units a person can feel.
04 Information
What is priced, what is rumor, what would change your mind. The memo is how information becomes a decision.
05 Plumbing
Clearinghouses, settlement cycles, margin, collateral, fails. Most blow-ups start here, not in the narrative.
Then writing
None of the five domains count until they survive one page another adult can mark.