Webull

Webull is a commission-free online brokerage whose Webull OpenAPI platform gives quantitative and algorithmic traders programmatic access to trading and market data across US and Hong Kong regions. It exposes four API products — a Trading API (place/preview/replace/cancel orders for stocks, options, futures, crypto, and event contracts, including combo OTO/OCO/OTOCO and TWAP/VWAP/POV algo orders), a Market Data API (real-time and historical snapshots, ticks, quotes/depth, footprint and OHLCV bars), a Broker API (enterprise account opening, funding, and cash journals), and a Connect API (OAuth 2.0 third-party authorization). Requests are authenticated with an App Key / App Secret pair and HMAC-SHA1 request signing, with real-time streaming over gRPC (trading events) and MQTT (market data). Webull ships official Python and Java SDKs, a Go CLI, a published MCP server, and an Agent Skill.

Webull publishes 3 APIs on the APIs.io network. Tagged areas include Company, Technology, Financial-Services, Brokerage, and Trading.

The Webull catalog on APIs.io includes 1 event-driven AsyncAPI specification.

Webull’s developer surface includes documentation, API reference, getting-started guide, changelog, authentication, CLI, sandbox, and 17 more developer resources.

🌐 Visit website 📡 Source on GitHub
38.1/100 thin ▬ flat Agent 41/100 agent ready Full breakdown ↓
scored 2026-08-20 · rubric v0.12.0
AccessSelf serve
3 APIs 1 MCP Servers
CompanyTechnologyFinancial-ServicesBrokerageTradingStock MarketMarket DataInvestingFintechCryptocurrency

Kin Score

Kin Score Kin Score How this is scored →
scored 2026-08-20 · rubric v0.12.0
Composite quality — 38.1/100 · thin
Contract Quality 9.6 / 21
Developer Ergonomics 13.4 / 17
Access Clarity 0.0 / 17
Operational Transparency 2.9 / 11
Contract Governance 0.5 / 10
Discoverability 6.9 / 9
Regulatory Posture 4.2 / 15
Agent readiness — 41/100 · agent ready
Machine-Readable Contract 18 / 18
Agentic Access Contract 0 / 10
Documented Reversibility 0 / 6
MCP Server 0 / 12
Machine-Readable Auth 10 / 10
Idempotency 9 / 9
Stable Error Semantics 8 / 8
Request/Response Examples 0 / 7
Rate-Limit Signaling 0 / 7
Typed Event Surface 6 / 6
Agent Skills 5 / 5
Well-Known Catalog 0 / 4
Consent & Bot Identity 0 / 3
A2A Agent Card 0 / 8
Dry-Run / Simulate Mode 0 / 4
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.
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/. This rating is computed from github.com/api-evangelist/webull: open an issue to ask a question, or submit a pull request to add artifacts. Want it done for you? Prioritized profiling — $2,500 →

APIs 3

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

Webull Trading API

Order management across stocks, options, futures, crypto, and event contracts — place, preview, replace, cancel, batch (combo OTO/OCO/OTOCO), and algo (TWAP/VWAP/POV) orders, pl...

Webull Market Data API

Real-time and historical market data — snapshots, tick data, quotes/depth, footprint, and OHLCV bars for stocks, futures, crypto, and event contracts, over HTTP and MQTT streaming.

Webull Connect API

OAuth 2.0 third-party integration for authorizing access to a Webull user's account.

MCP Servers 1

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

Webull MCP Server

MCP SERVER

Event Specifications 1

AsyncAPI definitions for this provider's event-driven and streaming APIs.

Webull Events Webhooks

ASYNCAPI

Security Posture 2

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

Webull Authentication

apiKey/http-signature/oauth2 · 3 schemes

SECURITY

Webull Domain Security

TLSv1.3 · HSTS · DMARC

SECURITY

Resources

Get Started 3

Portal, sign-up, and the first successful call

DeveloperPortal
DeveloperPortal
 GettingStarted
GettingStarted
 Sandbox
Sandbox

Documentation 2

Reference material describing how the API behaves

Documentation
Documentation
 APIReference
APIReference

Agent Surfaces 4

MCP servers, agent skills, and machine-readable catalogs

MCPServer
MCPServer
 AgentSkill
AgentSkill
 LLMsTxt
LLMsTxt
 WellKnown
WellKnown

Design & Contract 6

Pagination, idempotency, versioning, errors, and events

Webhooks
Webhooks
 Conventions
Conventions
 Idempotency
Idempotency
 Conformance
Conformance
 ErrorCatalog
ErrorCatalog
 Lifecycle
Lifecycle

Build 4

SDKs, sample code, and the tooling you integrate with

GitHubOrganization
GitHubOrganization
 SDKs
SDKs
 Packages
Packages
 CLI
CLI

Access & Security 2

Authentication, authorization, and security posture

DomainSecurity
DomainSecurity
 Authentication
Authentication

Operate 1

Status, limits, changes, and where to get help

ChangeLog
ChangeLog

Company 1

The organization behind the API

Website
Website

Other 1

Properties that don't map to a standard resource type

Protobuf
Protobuf

Source (apis.yml)

apis.yml Raw ↑ 
aid: webull
name: Webull
description: Webull is a commission-free online brokerage whose Webull OpenAPI platform gives quantitative and algorithmic
  traders programmatic access to trading and market data across US and Hong Kong regions. It exposes four API products — a
  Trading API (place/preview/replace/cancel orders for stocks, options, futures, crypto, and event contracts, including combo
  OTO/OCO/OTOCO and TWAP/VWAP/POV algo orders), a Market Data API (real-time and historical snapshots, ticks, quotes/depth,
  footprint and OHLCV bars), a Broker API (enterprise account opening, funding, and cash journals), and a Connect API (OAuth
  2.0 third-party authorization). Requests are authenticated with an App Key / App Secret pair and HMAC-SHA1 request signing,
  with real-time streaming over gRPC (trading events) and MQTT (market data). Webull ships official Python and Java SDKs,
  a Go CLI, a published MCP server, and an Agent Skill.
url: https://raw.githubusercontent.com/api-evangelist/webull/refs/heads/main/apis.yml
x-type: company
x-source: vc-portfolio
x-backed-by:
- hongshan
- lightspeed-venture-partners
x-tier: stub
x-tier-reason: portfolio-lead
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: '2026-07-21'
image: https://www.webull.com/favicon.ico
tags:
- Company
- Technology
- Financial-Services
- Brokerage
- Trading
- Stock Market
- Market Data
- Investing
- Fintech
- Cryptocurrency
tags_raw:
- Company
- Technology
- Financial Services
- Brokerage
- Trading
- Stock Market
- Market Data
- Investing
- Fintech
- Cryptocurrency
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com
- FN: APIs.json
  email: info@apis.io
apis:
- name: Webull Trading API
  description: Order management across stocks, options, futures, crypto, and event contracts — place, preview, replace, cancel,
    batch (combo OTO/OCO/OTOCO), and algo (TWAP/VWAP/POV) orders, plus accounts, balances, positions, and instruments.
  humanURL: https://developer.webull.com/apis/docs/webull-open-api-reference
  baseURL: https://api.webull.com
  tags:
  - Trading
  - Order
  - Brokerage
  tags_raw:
  - Trading
  - Orders
  - Brokerage
  properties:
  - type: Documentation
    url: https://developer.webull.com/apis/docs/webull-open-api-reference
- name: Webull Market Data API
  description: Real-time and historical market data — snapshots, tick data, quotes/depth, footprint, and OHLCV bars for stocks,
    futures, crypto, and event contracts, over HTTP and MQTT streaming.
  humanURL: https://developer.webull.com/apis/docs/market-data-api/subscribe-quotes
  baseURL: https://api.webull.com
  tags:
  - Market Data
  - Quotes
  - Streaming
  properties:
  - type: Documentation
    url: https://developer.webull.com/apis/docs/market-data-api/subscribe-quotes
- name: Webull Connect API
  description: OAuth 2.0 third-party integration for authorizing access to a Webull user's account.
  humanURL: https://developer.webull.com/apis/docs
  baseURL: https://api.webull.com
  tags:
  - Authentication
  - Authorization
  tags_raw:
  - OAuth
  - Authorization
x-enrichment:
  date: '2026-07-21'
  status: enriched
  artifacts_added: 16
  pass: local-v1
common:
- type: DomainSecurity
  url: security/webull-domain-security.yml
- type: Website
  url: https://webull.com
- type: DeveloperPortal
  url: https://developer.webull.com/apis/home
- type: Documentation
  url: https://developer.webull.com/apis/docs/webull-open-api-reference
- type: APIReference
  url: https://developer.webull.com/apis/docs/webull-open-api-reference
- type: GettingStarted
  url: https://developer.webull.com/apis/docs/getting-started
- type: ChangeLog
  url: https://developer.webull.com/apis/docs/changelog
- type: GitHubOrganization
  url: https://github.com/webull-inc
- type: Authentication
  url: authentication/webull-authentication.yml
- type: SDKs
  url: packages/webull-packages.yml
- type: Packages
  url: packages/webull-packages.yml
- type: CLI
  url: cli/webull-cli.yml
- type: MCPServer
  url: mcp/webull-mcp.yml
- type: AgentSkill
  url: skills/_index.yml
- type: LLMsTxt
  url: llms/webull-llms.txt
- type: Protobuf
  url: grpc/webull-events.proto
- type: Webhooks
  url: asyncapi/webull-events-webhooks.yml
- type: Conventions
  url: conventions/webull-conventions.yml
- type: Idempotency
  url: conventions/webull-conventions.yml
- type: Conformance
  url: conformance/webull-conformance.yml
- type: ErrorCatalog
  url: errors/webull-error-codes.yml
- type: Lifecycle
  url: lifecycle/webull-lifecycle.yml
- type: Sandbox
  url: sandbox/webull-sandbox.yml
- type: WellKnown
  url: well-known/webull-well-known.yml