Public website screenshot

Public

Public (Public Holdings, Inc.) is a multi-asset investing platform where people can trade stocks, ETFs, options, index options, crypto, bonds, and treasuries, and hold IRAs, direct indexing, high-yield cash, and margin in one account. Public positions itself as an "agentic brokerage" and ships a public Trading API (api.public.com) that lets developers programmatically manage accounts, pull market data, and place equity, crypto, and options orders with commission-free execution and options rebates. It also operates a hosted, OAuth-secured MCP server (mcp.public.com) so AI assistants like Claude and ChatGPT can query portfolios and trade on a user's behalf, alongside an official Python SDK, command-line interface, and Postman collection. Backed by Accel.

Public publishes 1 API on the APIs.io network. Tagged areas include Company, Consumer, Investing, Brokerage, and Trading.

Public’s developer surface includes documentation, getting-started guide, changelog, signup flow, pricing, support, engineering blog, and 18 more developer resources.

🌐 Visit website 📡 Source on GitHub
38.4/100 thin ▬ flat Agent 15/100 agent aware saas Full breakdown ↓
scored 2026-09-08 · rubric v0.20.0
AccessSelf serve
1 APIs 1 MCP Servers
CompanyConsumerInvestingBrokerageTradingFintechStocksOptionsCryptoMarket DataAgenticMCP

Kin Score

Kin Score Kin Score How this is scored →
scored 2026-09-08 · rubric v0.20.0
Composite quality — 38.4/100 · thin
Contract Quality 0.0 / 21
Developer Ergonomics 11.7 / 17
Access Clarity 7.6 / 17
Operational Transparency 2.0 / 11
Contract Governance 1.9 / 10
Discoverability 6.5 / 9
Regulatory Posture 8.7 / 15
Agent readiness — 15/100 · agent aware
Machine-Readable Contract 0 / 18
Agentic Access Contract 0 / 10
Documented Reversibility 0 / 6
MCP Server 12 / 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 0 / 6
Protected Resource Metadata 5 / 5
Registration Without a Human 0 / 6
Agentic Commerce Well-Known Document 0 / 5
Regulatory Posture applies to this provider. Its tags matched the Securities & Market Data 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/public: 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 →

APIs 1

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

Public Trading API

REST API for programmatic trading on Public — manage brokerage accounts, pull portfolio and transaction history, retrieve market data (quotes, bars, option chains, greeks), and ...

MCP Servers 1

Model Context Protocol servers that expose these APIs to AI agents.

Public MCP Server

Public's hosted, remote MCP server — described by Public as part of "the world's first agentic brokerage." Lets AI assistants query portfolios and place trades on a connected Pu...

MCP SERVER

Security Posture 2

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

Public Authentication

http/oauth2 · 2 schemes

SECURITY

Public Domain Security

TLSv1.3 · HSTS · DMARC

SECURITY

Scopes 1

OAuth scopes governing access to this provider's APIs.

Public Scopes

4 scopes

4 scopes

SCOPES

Resources

Get Started 3

Portal, sign-up, and the first successful call

DeveloperPortal
DeveloperPortal
 GettingStarted
GettingStarted
 SignUp
SignUp

Documentation 1

Reference material describing how the API behaves

Documentation
Documentation

Agent Surfaces 3

MCP servers, agent skills, and machine-readable catalogs

MCPServer
MCPServer
 WellKnown
WellKnown
 LLMsTxt
LLMsTxt

Design & Contract 3

Pagination, idempotency, versioning, errors, and events

Conventions
Conventions
 Conformance
Conformance
 Lifecycle
Lifecycle

Build 5

SDKs, sample code, and the tooling you integrate with

GitHubOrganization
GitHubOrganization
 Packages
Packages
 SDKs
SDKs
 CLI
CLI
 Postman
Postman

Access & Security 3

Authentication, authorization, and security posture

DomainSecurity
DomainSecurity
 Authentication
Authentication
 OAuthScopes
OAuthScopes

Operate 2

Status, limits, changes, and where to get help

ChangeLog
ChangeLog
 Support
Support

Commercial 3

Pricing, plans, and the legal terms of use

Pricing
Pricing
 TermsOfService
TermsOfService
 PrivacyPolicy
PrivacyPolicy

Company 2

The organization behind the API

Website
Website
 Blog
Blog

Source (apis.yml)

apis.yml Raw ↑ 
x-enrichment:
  date: '2026-07-20'
  status: enriched
  artifacts_added: 12
  pass: local-v1
aid: public
name: Public
description: Public (Public Holdings, Inc.) is a multi-asset investing platform where people can trade stocks, ETFs, options,
  index options, crypto, bonds, and treasuries, and hold IRAs, direct indexing, high-yield cash, and margin in one account.
  Public positions itself as an "agentic brokerage" and ships a public Trading API (api.public.com) that lets developers programmatically
  manage accounts, pull market data, and place equity, crypto, and options orders with commission-free execution and options
  rebates. It also operates a hosted, OAuth-secured MCP server (mcp.public.com) so AI assistants like Claude and ChatGPT can
  query portfolios and trade on a user's behalf, alongside an official Python SDK, command-line interface, and Postman collection.
  Backed by Accel.
url: https://raw.githubusercontent.com/api-evangelist/public/refs/heads/main/apis.yml
x-type: company
x-source: vc-portfolio
x-backed-by:
- accel
x-tier: stub
x-tier-reason: portfolio-lead
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: self-serve
  trial: false
  try_now: false
  public: false
  label: Self-serve signup
  confidence: medium
  source:
  - authentication
  generated: '2026-07-22'
  method: derived
specificationVersion: '0.23'
created: '2026-07-17'
modified: '2026-07-20'
tags:
- Company
- Consumer
- Investing
- Brokerage
- Trading
- Fintech
- Stocks
- Options
- Crypto
- Market Data
- Agentic
- MCP
image: https://public.com/favicon.ico
apis:
- name: Public Trading API
  description: REST API for programmatic trading on Public — manage brokerage accounts, pull portfolio and transaction history,
    retrieve market data (quotes, bars, option chains, greeks), and place, replace, and cancel equity, crypto, and multi-leg
    options orders. Authentication exchanges a long-lived secret key for a short-lived bearer JWT access token.
  humanURL: https://public.com/api/docs
  baseURL: https://api.public.com
  tags:
  - Trading
  - Market Data
  - Brokerage
  - Options
  - Crypto
  properties:
  - type: Documentation
    url: https://public.com/api/docs
  - type: Quickstart
    url: https://public.com/api/docs/quickstart
  - type: Authentication
    url: authentication/public-authentication.yml
  - type: OAuthScopes
    url: scopes/public-scopes.yml
  - type: ChangeLog
    url: https://public.com/api/docs/changelog
  - type: SDKs
    url: packages/public-packages.yml
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com
- FN: APIs.json
  email: info@apis.io
common:
- type: DomainSecurity
  url: security/public-domain-security.yml
- type: Website
  url: https://public.com
- type: DeveloperPortal
  url: https://public.com/api
- type: Documentation
  url: https://public.com/api/docs
- type: GettingStarted
  url: https://public.com/api/docs/quickstart
- type: ChangeLog
  url: changelog/public-changelog.yml
- type: SignUp
  url: https://public.com/signup
- type: Pricing
  url: https://public.com/disclosures/fee-schedule
- type: TermsOfService
  url: https://public.com/terms-of-service
- type: PrivacyPolicy
  url: https://public.com/privacy-policy
- type: Support
  url: https://help.public.com
- type: Blog
  url: https://public.com/learn
- type: GitHubOrganization
  url: https://github.com/PublicDotCom
- type: Packages
  url: packages/public-packages.yml
- type: SDKs
  url: packages/public-packages.yml
- type: CLI
  url: cli/public-cli.yml
- type: MCPServer
  url: mcp/public-mcp.yml
- type: WellKnown
  url: well-known/public-well-known.yml
- type: LLMsTxt
  url: llms/public-llms.txt
- type: Authentication
  url: authentication/public-authentication.yml
- type: OAuthScopes
  url: scopes/public-scopes.yml
- type: Conventions
  url: conventions/public-conventions.yml
- type: Conformance
  url: conformance/public-conformance.yml
- type: Lifecycle
  url: lifecycle/public-lifecycle.yml
- type: Postman
  url: https://github.com/PublicDotCom/postman-collection

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