Sandbox environment. Interpose is not a registered broker-dealer and holds no FINRA approval. Every API documented here is available in a simulated evaluation environment only — no client assets are held, no real trades are executed, and no custody is provided. The calculation engines are the production code paths; fills, custody, settlement and KYC decisioning are simulated. What is real and what is simulated →
API Reference
Portfolio Management
The Portfolio Management operations an API key can reach — portfolios and sleeves, the model library, rebalancing runs, TWR and MWR performance, custodian overlay connections, AUM billing, disclosures and more. The reference is generated from the service code, using the same scope rules that decide what a key can reach, so an operation open only to a signed-in portal user is not in it. Base URL https://interposehq.com/api/pm; every path below starts with /v1.
Two things this page will not teach you. Rebalancing is asynchronous and has an explicit approval step, which the endpoint reference walks through end to end. And performance is computed per account rather than per portfolio, with returns as decimal fractions — see API conventions.