> ## Documentation Index
> Fetch the complete documentation index at: https://docs.sumvin.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Platform API vs SIS

> Where Sumvin splits the integrator surface — consumer-app calls vs credential verification.

# Platform API vs SIS

Sumvin is four products — <Tooltip headline="Sigil" tip="Sumvin's portable, KYC-verified identity — Proof of Personhood." cta="Glossary →" href="/glossary">Sigil</Tooltip> (verified identity), <Tooltip headline="Errand" tip="An agent's scope-bound tasking run: Intent → Authorization → Vigilance." cta="Glossary →" href="/glossary">Errand</Tooltip> (agent tasking), <Tooltip headline="Envoy" tip="The money agent that acts on a user's behalf." cta="Glossary →" href="/glossary">Envoy</Tooltip> (the money agent), and <Tooltip headline="Atomic Money" tip="Sumvin's payments umbrella: ramps, card issuing, x402, and payment links." cta="Glossary →" href="/glossary">Atomic Money</Tooltip> (payments) — reached through two distinct API surfaces. This page is about which surface you call, not which product you build.

<Snippet file="product-term-disambiguation.mdx" />

The **Platform API** is what a consumer app calls on behalf of a user to build with those products — create a user (Sigil), run KYC, manage wallets and cards (Atomic Money), kick off an Errand. The **SIS API** (Sumvin Identity Service) is the issuer side of the identity layer — it exchanges a signed <Tooltip headline="Stamped Mandate" tip="A signed authorisation a user grants for specific scoped actions — delivered on the wire as a PINT." cta="Glossary →" href="/glossary">Stamped Mandate</Tooltip> for a JWT, publishes the JWKS verifiers use, answers revocation checks, and looks up user data by SRI. A verifier receiving a credential validates the JWT **locally** against the cached JWKS — no per-request SIS call — and only calls the SIS API when it opts into a fresh revocation check or needs to exchange a Stamped Mandate.

You pick the surface by the job you're doing, not by the user you're acting for.

## What each surface owns

| Surface          | Owns                                                                                                                | Typical caller                                                                        |
| ---------------- | ------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------- |
| **Platform API** | Users, onboarding state, KYC (Sigil), wallets (EOA + Safe), Errands, cards, strategies, transactions (Atomic Money) | Partner backend acting on behalf of an authenticated user                             |
| **SIS API**      | Stamped Mandate exchange, JWT issuance, JWKS, revocation, SRI-to-user lookup, dashboard auth config                 | Partner backend doing token exchange; verifier backend for optional revocation/lookup |

## Where they meet

A user created via the Platform API is identified system-wide by their [SRI](/identity/sri) — the wire identity behind Sigil. Their signed Stamped Mandates ([PINTs](/identity/pint) on the wire) are exchanged for JWTs at the SIS API. The JWT's `sub` claim is the same SRI the Platform API uses — the two surfaces are joined at the identity layer, not at the transport layer.

## Which one am I calling

* Building a consumer app that onboards and authenticates its own users → **Platform API**.
* Verifying inbound credentials → validate the JWT locally against the SIS JWKS; call the SIS API only for token exchange or optional revocation. See the [Verifier guide](/merchant/overview).
* Federating your own auth provider (Dynamic, Privy, SIWE) into Sumvin's identity graph → **SIS Dashboard**.

The auth model differs between the two: the Platform API uses `x-juno-jwt` from your auth provider; the SIS API uses a partner-issued API key. See [Auth model](/concepts/auth-model) for the full matrix.

## See also

* [Platform map](/overview/platform-map) — the visual version of this split
* [Sumvin Identity overview](/identity/overview) — why SIS exists
* [Auth model](/concepts/auth-model) — which credential goes where

## Referenced from

* [Introduction](/introduction)
* [Authentication](/authentication)
* [SIS Dashboard introduction](/dashboard/introduction)