What makes series separation actually hold for AI agents?

Quinn ran her agent Alfie across two series and assumed the formation filing did the work. But a series wall is a documented structure, not a guarantee, and what makes the separation hold depends on observing the formalities — it has to be performed, not recited. So Quinn kept separate books for each series, each with a named human Member and Manager; Alfie, a tool with no legal capacity, signed only as an authorized signer under a capped mandate, never in his own name. Funds for one series stayed in that series' account; nothing crossed over. Every entry reconciled — the records of what Alfie did matched the ledger of what each series held, so an outsider could trace any dollar to its series without untangling it. That observed separateness — separate books, reconcilable records, formalities watched day to day — is the work the wall asks for. The structure is named; the separation is performed in the keeping.