# PolySign

**Canonical:** https://apis.io/providers/polysign/  
**Website:** https://www.polysign.io/  
**APIs profiled:** 17

PolySign, Inc. is an Oakland / San Francisco / New York financial technology company building blockchain-enabled infrastructure for institutional digital asset capital markets and payments. Founded by Arthur Britto, David Schwartz and Jack McDonald, PolySign operates a third-generation permissioned blockchain and the AtomicNet settlement network, and was the parent of Standard Custody & Trust Company, the NYDFS-regulated digital asset custody, trading and settlement platform acquired by Ripple in 2024. PolySign publishes three OpenAPI 3.0.3 contracts for AtomicNet — the AtomicNet API Server (node interface for assets, orders, escrow and beneficiary authorizations, settlements, settlement confirmations, book transfers, partners and investors), the AtomicNet Merchant Gate Node, and the AtomicNet ABC Proxy Service (account registration, digest memorialization, signing and testnet faucet) — all authenticated with OAuth 2.0 client credentials issued by a PolySign-hosted token endpoint.

## Kin Score — 29.1 / 100 (thin)

Scored 2026-08-25 under rubric 0.14.0. Trend: flat (-0.7 from 29.8).

| Facet | Score |
|---|---|
| Discoverability | 64.8 |
| Contract Quality | 41.3 |
| Governance | 16.7 |
| Contract Governance | 16.7 |
| Operational Transparency | 2.6 |
| Developer Ergonomics | 42.3 |
| Commercial Clarity | 0.0 |
| Access Clarity | 0.0 |

Regulatory layer — **Payments**: 42.2 (matched via tags).

## Agent readiness — 24.6 (agent-aware)

| Dimension | Value |
|---|---|
| Spec Presence | yes |
| Agentic Access | no |
| Reversibility Documented | no |
| MCP Server | no |
| Auth Clarity | negotiable |
| Idempotency | no |
| Error Semantics | documented |
| OpenAPI Examples | partial |
| Rate Limit Signal | no |
| Event Surface Described | no |
| Agent Skills | derived |
| Well Known Catalog | no |
| Consent Identity | no |
| Agent Card | no |
| Dry Run Mode | no |
| Delegated Identity | no |
| Protected Resource Metadata | no |
| Dynamic Client Registration | no |
| Agentic Commerce | no |

## APIs (17)

- **PolySign ABC Accounts API** — The ABC Accounts API from PolySign — 3 operation(s) for abc accounts.
- **PolySign ABC Memorials API** — The ABC Memorials API from PolySign — 2 operation(s) for abc memorials.
- **PolySign ABC Signing API** — The ABC Signing API from PolySign — 1 operation(s) for abc signing.
- **PolySign ABC Testnet API** — The ABC Testnet API from PolySign — 2 operation(s) for abc testnet.
- **PolySign Asset API** — The asset API from PolySign — 5 operation(s) for asset.
- **PolySign Authentication API** — The authentication API from PolySign — 1 operation(s) for authentication.
- **PolySign beneficiary authorization API** — The beneficiary authorization API from PolySign — 6 operation(s) for beneficiary authorization.
- **PolySign book transfer API** — The book transfer API from PolySign — 5 operation(s) for book transfer.
- **PolySign book transfer confirmation API** — The book transfer confirmation API from PolySign — 4 operation(s) for book transfer confirmation.
- **PolySign escrow authorization API** — The escrow authorization API from PolySign — 6 operation(s) for escrow authorization.
- **PolySign Investor API** — The investor API from PolySign — 2 operation(s) for investor.
- **PolySign Order API** — The order API from PolySign — 5 operation(s) for order.
- **PolySign Partner API** — The partner API from PolySign — 3 operation(s) for partner.
- **PolySign Settlement API** — The settlement API from PolySign — 5 operation(s) for settlement.
- **PolySign settlement confirmation API** — The settlement confirmation API from PolySign — 6 operation(s) for settlement confirmation.
- **PolySign System API** — The system API from PolySign — 4 operation(s) for system.
- **PolySign Utility API** — The utility API from PolySign — 5 operation(s) for utility.

## MCP servers (1)

- **PolySign MCP Server**

## Security (2)

- **Polysign Authentication** — oauth2 · 1 scheme
- **Polysign Domain Security** — TLSv1.3 · DMARC

## Tags

Digital Assets, Blockchain, institutional-custody, Settlement, Escrow, Capital Markets, Payments, Fintech, Distributed Ledger, atomicnet

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Profiled by [API Evangelist](https://apievangelist.com) and published on [APIs.io](https://apis.io/providers/polysign/). Scores are computed from the provider's own public artifacts under a published rubric.