Vault12

Vault12 is a non-custodial crypto asset security company whose Vault12 Guard mobile app backs up wallet seed phrases and private keys using Shamir's Secret Sharing across a decentralized network of appointed Guardians, with designated legacy contacts for crypto inheritance — no cloud storage and no custody of funds. Its developer surface is open source, centered on the Zax NaCl-based cryptographic relay (asynchronous end-to-end-encrypted device-to-device messaging and file exchange), the glow.ts client library, and native Shamir's Secret Sharing implementations, plus RFC 8414 OAuth 2.0 authorization-server metadata published on vault12.com and a public Zax test relay at zt.vault12.com.

Vault12 is listed with 1 API on the APIs.io network. Tagged areas include Company, Cryptocurrency, Security, Backup, and Inheritance.

Vault12’s developer surface includes engineering blog, support, pricing, authentication, sandbox, changelog, and 17 more developer resources.

🌐 Visit website 📡 Profile data on GitHub

33.1/100 thin ▬ flat Agent 15/100 agent aware Front door AI 1/6 silent Heartbeat 60/100 alive open core · MIT Full breakdown ↓
scored 2026-11-06 · rubric v0.27.0 · Show this score on your site →

AccessSelf serve

1 API

Company Cryptocurrency Security BackupInheritanceWallets CryptographySecret SharingKey Management

Kin Score

Kin Score How this is scored →
scored 2026-11-06 · rubric v0.27.0

Composite quality — 33.1/100 · thin

Contract Quality 0.0 / 19

Developer Ergonomics 7.5 / 15

Access Clarity 4.7 / 15

Operational Transparency 2.6 / 10

Contract Governance 1.6 / 9

Discoverability 5.5 / 8

Regulatory Posture 4.7 / 15

Open Source Surface 5.0 / 10

Agent readiness — 15/100 · agent aware

Machine-Readable Contract 0 / 18

Agentic Access Contract 0 / 10

Documented Reversibility 0 / 6

MCP Server 0 / 12

Machine-Readable Auth 10 / 10

Idempotency 0 / 9

Stable Error Semantics 0 / 8

Request/Response Examples 0 / 7

Rate-Limit Signaling 0 / 7

Typed Event Surface 0 / 6

Agent Skills 0 / 5

Well-Known Catalog 0 / 4

Consent & Bot Identity 0 / 3

A2A Agent Card 0 / 8

Dry-Run / Simulate Mode 0 / 4

Delegated User Identity 6 / 6

Protected Resource Metadata 0 / 5

Registration Without a Human 6 / 6

Agentic Commerce Well-Known Document 0 / 5

Pagination 5 / 5

Distinct Operations 3 / 3

MCP Tool Quality 6 / 6

Regulatory Posture applies to this provider. Its tags matched the Payments regime, so Regulatory Posture carries 15 points of the composite. If this regime is wrong for your business, say so on your provider repo — the applicability map is public and we will correct it.

Open Source Surface applies to this provider. This product is open source and we read its repository directly, so Open Source Surface carries 10 points of the composite. It is scored from what the repository actually publishes — a security policy, a contribution guide, a release history, a code of conduct — read live from the provider rather than inferred from our own catalog pointers. This facet adds; nothing was taken away to make room for it. An open-source project is not excused from the commercial facets, because exemption would strip it of the points it does earn. If we have the wrong repository, or this product is not open source, say so on your provider repo and we will drop the facet rather than have you publish against it.

Create-or-Update Ergonomics could not be measured. We hold no machine-readable contract for this provider to read, so there is nothing to measure a write surface against. Excluded rather than scored zero: never-measured and measured-empty are different facts. Publishing an OpenAPI is what makes this facet — and several others — scorable at all.

The six quality facets above are damped to 75 points between them, because both conditional facets apply and carry 25 points together. That is why each facet's contribution is shown against a damped maximum: raising a quality facet moves the composite by 75% of its nominal weight, not 100%. The full arithmetic is at apis.io/rating/.

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Agent readiness — checks not met, largest first (exact, from this profile):

Machine-Readable Contract +18 pts — api_specs includes an OpenAPI document
MCP Server +12 pts — deployment.mode + probe verdict on the mcp/ manifest, not the pointer; an unprobed slug falls back to authorship
Agentic Access Contract +10 pts — agentic_access artifact present (x-agentic-access), graded by author
Idempotency +9 pts — OpenAPI mutating operations declare an idempotency key — a header, a request-body property, or a named de-duplication token whose own description says so (verified); else common[].type matches /idempoten/i (documented)
Stable Error Semantics +8 pts — OpenAPI $refs a shared error schema across 4xx/5xx responses (verified), else common[].type includes ErrorCatalog / ErrorCodes / DeclineCodes
A2A Agent Card +8 pts — a2a/-a2a.yml manifest, graded on conformance.grade against A2A 1.0.0

10 more unmet checks in the Agent Readiness table above.

Kin Score — facets with the most composite points still available (weight × headroom):

Contract Quality scores 0.0 — up to +25.0 composite points
Access Clarity scores 31.6 — up to +13.7 composite points
Developer Ergonomics scores 50.0 — up to +10.0 composite points

Each check links to what satisfies it. Publish the artifact, or tell us where it already lives, and the score moves on the next scoring run.

Improve this rating by publishing the missing artifacts — every area above can be raised, and the full rubric is at apis.io/rating/. Every facet and dimension name above is a link: it opens that measurement's own page — what it means, the exact checks that feed it, how the whole catalog distributes on it, and the providers at the top of it. This rating is computed from the provider profile at artifacts.apis.io/vault12/apis.yml: open an issue on github.com/api-evangelist/vault12 to ask a question or point us at an artifact you publish. Submit an artifact on GitHub — free → Manage your own listing — the Influence plan, $499/mo →

Standards implemented 1

Standards this provider implements or carries. De facto ones are profiled and measured by the API Commons; formal ones come from the standards directory and are linked by the provider's own tags. The evidence column says how each claim was established — not that it was made.

Dynamic Client Registration

measured — observed by APIs.io (published)

APIs 1

Individual APIs this provider publishes, each with its own machine-readable definition.

Vault12 Zax Cryptographic Relay API

Open-source NaCl-based cryptographic relay operated as asynchronous "dead drops" for end-to-end-encrypted device-to-device communication. Clients establish anonymous session key...

Service Levels 1

Uptime the provider promises or reports, as SLA4OAI. Read from its own pages; APIs.io runs no monitors.

Vault12

SLA

Security Posture 2

Authentication, domain security, vulnerability disclosure, and trust-center signals.

Vault12 Authentication

oauth2/session-handshake · 2 schemes

SECURITY

Vault12 Domain Security

TLSv1.3 · HSTS · DNSSEC · DMARC

SECURITY

Scopes 1

OAuth scopes governing access to this provider's APIs.

Vault12 Scopes

4 scopes · authorizationCode/implicit/password/refresh_token

4 scopes

SCOPES

Resources

Get Started 1

Portal, sign-up, and the first successful call

Sandbox

Sandbox

Documentation 1

Reference material describing how the API behaves

ContributionGuide

ContributionGuide

Agent Surfaces 2

MCP servers, agent skills, and machine-readable catalogs

WellKnown

WellKnown

LLMsTxt

LLMsTxt

Design & Contract 2

Pagination, idempotency, versioning, errors, and events

Conformance

Conformance

Lifecycle

Lifecycle

Build 3

SDKs, sample code, and the tooling you integrate with

GitHubOrganization

GitHubOrganization

Packages

Packages

SDKs

SDKs

Access & Security 3

Authentication, authorization, and security posture

DomainSecurity

DomainSecurity

OAuthScopes

OAuthScopes

Authentication

Authentication

Operate 5

Status, limits, changes, and where to get help

IssueTracker

Releases

Support

StatusPage

ChangeLog

Commercial 4

Pricing, plans, and the legal terms of use

License

Pricing

TermsOfService

PrivacyPolicy

Company 2

The organization behind the API

Website

Website

Blog

Blog

Source (apis.yml)

aid: vault12
name: Vault12
description: Vault12 is a non-custodial crypto asset security company whose Vault12 Guard mobile app backs up wallet seed
  phrases and private keys using Shamir's Secret Sharing across a decentralized network of appointed Guardians, with designated
  legacy contacts for crypto inheritance — no cloud storage and no custody of funds. Its developer surface is open source,
  centered on the Zax NaCl-based cryptographic relay (asynchronous end-to-end-encrypted device-to-device messaging and file
  exchange), the glow.ts client library, and native Shamir's Secret Sharing implementations, plus RFC 8414 OAuth 2.0 authorization-server
  metadata published on vault12.com and a public Zax test relay at zt.vault12.com.
url: https://raw.githubusercontent.com/api-evangelist/vault12/refs/heads/main/apis.yml
deliveryModel:
  model: open-core
  license: MIT
  open_source: true
  commercial: true
  callable_host: false
  label: Open core · an OSS project plus a commercial hosted product
  confidence: high
  source:
  - license
  - pricing
  generated: '2026-08-28'
  method: derived
accessModel:
  pricing: unknown
  onboarding: self-serve
  trial: false
  try_now: false
  public: false
  gated: none
  gated_source:
  - onboarding
  label: Self-serve signup
  confidence: medium
  source:
  - authentication
  - scopes
  - security
  - sandbox
  generated: '2026-11-06'
  method: derived
image: https://assets.rbl.ms/27528763/origin.png
x-type: company
x-source: vc-portfolio
x-backed-by:
- dcvc
x-tier: stub
x-tier-reason: portfolio-lead
specificationVersion: '0.23'
x-enrichment:
  date: '2026-07-21'
  status: enriched
  artifacts_added: 11
  pass: local-v1
created: '2026-07-17'
modified: '2026-07-21'
tags:
- Company
- Cryptocurrency
- Security
- Backup
- Inheritance
- Wallets
- Cryptography
- Secret Sharing
- Key Management
apis:
- name: Vault12 Zax Cryptographic Relay API
  description: Open-source NaCl-based cryptographic relay operated as asynchronous "dead drops" for end-to-end-encrypted device-to-device
    communication. Clients establish anonymous session keys via a proof-of-work handshake (POST /start_session, /verify_session)
    and then post encrypted commands to /command — upload, count, download, messageStatus, delete, plus the Zax 2.0 file-command
    family (startFileUpload, uploadFileChunk, downloadFileChunk, fileStatus, deleteFile). Vault12 maintains a public test
    relay with 30-minute message expiration.
  humanURL: https://github.com/vault12/zax
  baseURL: https://zt.vault12.com
  tags:
  - Relay
  - Cryptography
  - Messaging
  - File Exchange
  properties:
  - type: Documentation
    url: https://github.com/vault12/zax
  - type: APIReference
    url: https://s3-us-west-1.amazonaws.com/vault12/crypto_relay.pdf
  - type: SourceCode
    url: https://github.com/vault12/zax
  - type: Sandbox
    url: https://zt.vault12.com
common:
- type: IssueTracker
  url: https://github.com/vault12/zax/issues
- type: Releases
  url: https://github.com/vault12/zax/releases
- type: ContributionGuide
  url: https://github.com/vault12/zax/blob/main/CONTRIBUTING.md
- type: License
  name: MIT
  url: https://github.com/vault12/zax/blob/main/LICENSE
- type: DomainSecurity
  url: security/vault12-domain-security.yml
- type: Website
  url: https://vault12.com
- type: Blog
  url: https://vault12.com/blog/
- type: Support
  url: https://vault12.com/help/
- type: Pricing
  url: https://vault12.com/pricing/
- type: TermsOfService
  url: https://vault12.com/terms/
- type: PrivacyPolicy
  url: https://vault12.com/privacy/
- type: StatusPage
  url: https://status.vault12.com/
- type: GitHubOrganization
  url: https://github.com/vault12
- type: Packages
  url: packages/vault12-packages.yml
- type: SDKs
  url: packages/vault12-packages.yml
- type: WellKnown
  url: well-known/vault12-well-known.yml
- type: OAuthScopes
  url: scopes/vault12-scopes.yml
- type: Authentication
  url: authentication/vault12-authentication.yml
- type: Conformance
  url: conformance/vault12-conformance.yml
- type: LLMsTxt
  url: llms/vault12-llms.txt
- type: Sandbox
  url: sandbox/vault12-sandbox.yml
- type: Lifecycle
  url: lifecycle/vault12-lifecycle.yml
- type: ChangeLog
  url: changelog/vault12-changelog.yml
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com
- FN: APIs.json
  email: info@apis.io

Vault12 API — frequently asked questions

Does Vault12 have an API?

Yes. APIs.io lists 1 API from Vault12, including Vault12 Zax Cryptographic Relay API.

How do I authenticate with the Vault12 API?

Vault12 documents its authentication (oauth2/session-handshake · 2 schemes). The details are profiled on APIs.io as Vault12 Authentication.

Is the Vault12 API ready for AI agents?

Vault12 has a Kin Score of 33.1 out of 100 (thin) and an Agent Readiness score of 15.1 (agent-aware), scored by API Evangelist on 2026-11-06.

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