Principly

Principly, Inc. is an SEC-registered investment adviser that operates the consumer fintech product Backer (backer.com), a mobile-first platform for opening and managing 529 education savings plans. Backer lets parents open a 529 plan in minutes, automate contributions, and share custom gifting links so family and friends can contribute to a child's college fund. The service helps families choose among more than 100 U.S. 529 plans, reporting 250K+ users and $70M+ saved. It is a consumer-facing mobile and web application and does not publish a public developer API, documentation, or SDKs. Principly is backed by 500 Global and was added to the API Evangelist network as a portfolio company.

Principly is profiled on the APIs.io network. Tagged areas include Company, Fintech, Financial-Services, 529 Plans, and Education Savings.

Principly’s developer surface includes pricing, engineering blog, support, signup flow, and 4 more developer resources.

🌐 Visit website 📡 Source on GitHub

7.4/100 minimal ▬ flat Agent 0/100 human only saas Full breakdown ↓
scored 2026-09-14 · rubric v0.22.0

0 APIs

Company Fintech Financial-Services529 PlansEducation SavingsCollege SavingsConsumer FinanceInvestment AdviserMobile App

Kin Score

Kin Score How this is scored →
scored 2026-09-14 · rubric v0.22.0

Composite quality — 7.4/100 · minimal

Contract Quality 0.0 / 21

Developer Ergonomics 1.2 / 17

Access Clarity 2.9 / 17

Operational Transparency 0.0 / 11

Contract Governance 0.0 / 10

Discoverability 4.3 / 9

Regulatory Posture 1.7 / 15

Agent readiness — 0/100 · human only

Machine-Readable Contract 0 / 18

Agentic Access Contract 0 / 10

Documented Reversibility 0 / 6

MCP Server 0 / 12

Machine-Readable Auth 0 / 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 0 / 6

Protected Resource Metadata 0 / 5

Registration Without a Human 0 / 6

Agentic Commerce Well-Known Document 0 / 5

Regulatory Posture applies to this provider. Its tags matched the Education & Research 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.

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 85 points between them, because the conditional facet above carries the other 15. That is why each facet's contribution is shown against a damped maximum: raising a quality facet moves the composite by 85% of its nominal weight, not 100%. The full arithmetic is at apis.io/rating/.

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 github.com/api-evangelist/principly: open an issue to ask a question, or submit a pull request to add artifacts. Submit an artifact on GitHub — free → Manage your own listing — the Influence plan, $499/mo →

Security Posture 1

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

Principly Domain Security

TLSv1.3 · HSTS · DMARC

SECURITY

Resources

Get Started 2

Portal, sign-up, and the first successful call

SignUp

SignUp

Login

Access & Security 1

Authentication, authorization, and security posture

DomainSecurity

DomainSecurity

Operate 2

Status, limits, changes, and where to get help

HelpCenter

HelpCenter

Support

Support

Commercial 1

Pricing, plans, and the legal terms of use

Pricing

Pricing

Company 2

The organization behind the API

Website

Website

Blog

Blog

Source (apis.yml)

aid: principly
deliveryModel:
  model: saas
  open_source: false
  commercial: true
  callable_host: false
  label: Hosted service · you call their endpoint
  confidence: medium
  source:
  - pricing
  generated: '2026-08-28'
  method: derived
accessModel:
  pricing: unknown
  onboarding: unknown
  trial: false
  try_now: false
  public: false
  label: Unknown
  confidence: low
  source: []
  generated: '2026-07-22'
  method: derived
image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/icons/principly.png
name: Principly
description: Principly, Inc. is an SEC-registered investment adviser that operates the consumer fintech product Backer (backer.com),
  a mobile-first platform for opening and managing 529 education savings plans. Backer lets parents open a 529 plan in minutes,
  automate contributions, and share custom gifting links so family and friends can contribute to a child's college fund. The
  service helps families choose among more than 100 U.S. 529 plans, reporting 250K+ users and $70M+ saved. It is a consumer-facing
  mobile and web application and does not publish a public developer API, documentation, or SDKs. Principly is backed by 500
  Global and was added to the API Evangelist network as a portfolio company.
url: https://raw.githubusercontent.com/api-evangelist/principly/refs/heads/main/apis.yml
x-type: company
x-source: vc-portfolio
x-backed-by:
- 500-global
x-tier: stub
x-tier-reason: portfolio-lead
specificationVersion: '0.23'
created: '2026-07-17'
modified: '2026-07-20'
tags:
- Company
- Fintech
- Financial-Services
- 529 Plans
- Education Savings
- College Savings
- Consumer Finance
- Investment Adviser
- Mobile App
tags_raw:
- Company
- Fintech
- Financial Services
- 529 Plans
- Education Savings
- College Savings
- Consumer Finance
- Investment Adviser
- Mobile App
apis: []
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com
- FN: APIs.json
  email: info@apis.io
common:
- type: DomainSecurity
  url: security/principly-domain-security.yml
- type: Website
  url: https://backer.com
- type: Pricing
  url: https://backer.com/pricing
- type: Blog
  url: https://backer.com/blog
- type: HelpCenter
  url: https://help.backer.com/en/
- type: Support
  url: https://help.backer.com/en/
- type: SignUp
  url: https://app.backer.com/signup
- type: Login
  url: https://app.backer.com/signin
x-enrichment:
  date: '2026-07-20'
  status: minimal
  artifacts_added: 1
  pass: local-v1

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