Oddpool

Oddpool is an institutional-grade data platform for prediction markets, offering unified access to market data across Kalshi and Polymarket through a single REST API and WebSocket feed. It describes itself as "the search engine for prediction markets," normalizing hundreds of thousands of markets into a common model so quant funds, trading desks, and prosumer traders can search markets and events, pull tick-level historical orderbooks and OHLCV bars, track whale trades, detect cross-venue arbitrage, and stream real-time cross-venue probability distributions, orderbooks, and trades. Data is addressed by what (event and outcome keys) rather than by venue-specific tickers. A separate enterprise Reference Data API provides canonical cross-venue identifiers, fungibility classification, and a Wikidata cross-walk for institutional clients.

Oddpool publishes 1 API on the APIs.io network: WebSocket Feeds. Tagged areas include Company, Prediction Markets, Market Data, Financial Data, and Trading.

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

Oddpool’s developer surface includes documentation, API reference, getting-started guide, pricing, signup flow, support, authentication, and 14 more developer resources.

🌐 Visit website 📡 Source on GitHub

40.5/100 developing ▬ flat Agent 22/100 agent aware saas Full breakdown ↓
scored 2026-09-08 · rubric v0.20.0

2 APIs

Company Prediction Markets Market Data Financial Data Trading Fintech Data Aggregation WebSocket Historical DataKalshiPolymarket

Kin Score

Kin Score How this is scored →
scored 2026-09-08 · rubric v0.20.0

Composite quality — 40.5/100 · developing

Contract Quality 8.9 / 21

Developer Ergonomics 9.3 / 17

Access Clarity 7.6 / 17

Operational Transparency 0.9 / 11

Contract Governance 0.5 / 10

Discoverability 6.5 / 9

Regulatory Posture 6.3 / 15

Agent readiness — 22/100 · agent aware

Machine-Readable Contract 18 / 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 8 / 8

Request/Response Examples 0 / 7

Rate-Limit Signaling 7 / 7

Typed Event Surface 6 / 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 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/oddpool: 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 2

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

Oddpool API

REST API for prediction market data across Kalshi and Polymarket: full-text search over markets, events, and series; historical orderbook snapshots, top-of-book timeseries, trad...

Oddpool WebSocket Feeds

Single-connection WebSocket streaming real-time, normalized cross-venue prediction market data (dist, book, trade, and snapshot channels) for macro economic events and crypto (B...

Event Specifications 1

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

Oddpool WebSocket Feeds

Single-connection WebSocket streaming real-time, normalized cross-venue prediction market data from Kalshi and Polymarket. Data is addressed by what (event_key / outcome) not wh...

ASYNCAPI

Security Posture 2

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

Oddpool Authentication

apiKey · 2 schemes

SECURITY

Oddpool Domain Security

TLSv1.3 · HSTS · DMARC

SECURITY

Resources

Get Started 3

Portal, sign-up, and the first successful call

DeveloperPortal

DeveloperPortal

GettingStarted

GettingStarted

SignUp

SignUp

Documentation 3

Reference material describing how the API behaves

Documentation

Documentation

APIReference

APIReference

AsyncAPI

AsyncAPI

Agent Surfaces 2

MCP servers, agent skills, and machine-readable catalogs

LLMsTxt

LLMsTxt

X-MCPServerCandidate

X-MCPServerCandidate

Design & Contract 6

Pagination, idempotency, versioning, errors, and events

Conventions

ErrorCatalog

DataModel

Conformance

Lifecycle

Webhooks

Access & Security 2

Authentication, authorization, and security posture

Authentication

Authentication

DomainSecurity

DomainSecurity

Operate 1

Status, limits, changes, and where to get help

Support

Support

Commercial 3

Pricing, plans, and the legal terms of use

Pricing

Pricing

TermsOfService

TermsOfService

PrivacyPolicy

PrivacyPolicy

Company 1

The organization behind the API

Website

Website

Source (apis.yml)

aid: oddpool
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:
  - authentication
  - security
  generated: '2026-09-03'
  method: derived
image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/icons/oddpool.png
name: Oddpool
description: Oddpool is an institutional-grade data platform for prediction markets, offering unified access to market data
  across Kalshi and Polymarket through a single REST API and WebSocket feed. It describes itself as "the search engine for
  prediction markets," normalizing hundreds of thousands of markets into a common model so quant funds, trading desks, and
  prosumer traders can search markets and events, pull tick-level historical orderbooks and OHLCV bars, track whale trades,
  detect cross-venue arbitrage, and stream real-time cross-venue probability distributions, orderbooks, and trades. Data is
  addressed by what (event and outcome keys) rather than by venue-specific tickers. A separate enterprise Reference Data API
  provides canonical cross-venue identifiers, fungibility classification, and a Wikidata cross-walk for institutional clients.
url: https://raw.githubusercontent.com/api-evangelist/oddpool/refs/heads/main/apis.yml
x-type: company
x-source: vc-portfolio
x-backed-by:
- y-combinator
x-tier: stub
x-tier-reason: portfolio-lead
specificationVersion: '0.23'
created: '2026-07-17'
modified: '2026-07-20'
tags:
- Company
- Prediction Markets
- Market Data
- Financial Data
- Trading
- Fintech
- Data Aggregation
- WebSocket
- Historical Data
- Kalshi
- Polymarket
apis:
- name: Oddpool API
  description: 'REST API for prediction market data across Kalshi and Polymarket: full-text search over markets, events, and
    series; historical orderbook snapshots, top-of-book timeseries, trades, and OHLCV bars; whale-trade tracking; and cross-venue
    arbitrage and price-spread detection. Authenticated with an X-API-Key header and gated by subscription tier.'
  humanURL: https://docs.oddpool.com
  baseURL: https://api.oddpool.com
  tags:
  - Prediction Markets
  - Market Data
  - Historical Data
  - Arbitrage
  properties:
  - type: Documentation
    url: https://docs.oddpool.com
  - type: APIReference
    url: https://docs.oddpool.com/llms.txt
  - type: GettingStarted
    url: https://docs.oddpool.com/index.md
  - type: Authentication
    url: authentication/oddpool-authentication.yml
  - type: RateLimits
    url: https://docs.oddpool.com/rate-limits.md
  - type: ErrorCatalog
    url: errors/oddpool-problem-types.yml
  - type: Conventions
    url: conventions/oddpool-conventions.yml
  - type: DataModel
    url: data-model/oddpool-data-model.yml
  - type: X-MCPServerCandidate
    url: mcp/oddpool-mcp.yml
    note: 'Renamed from MCPServer 2026-09-03 (roadmap#247): the manifest self-describes as status: candidate — a tool list
      derived from the published API contracts, not an existing server. The scorer already read the manifest and reported
      mcp_server correctly; the MCPServer type was crediting the artifact-type surfaces with a server that does not exist.'
- name: Oddpool WebSocket Feeds
  description: Single-connection WebSocket streaming real-time, normalized cross-venue prediction market data (dist, book,
    trade, and snapshot channels) for macro economic events and crypto (BTC/ETH) markets enriched with Binance spot/futures
    reference data. Authenticated with an in-band auth message.
  humanURL: https://docs.oddpool.com/websocket/overview.md
  baseURL: wss://feeds.oddpool.com/ws
  tags:
  - WebSocket
  - Streaming
  - Real-Time
  tags_raw:
  - WebSocket
  - Streaming
  - Real-time
  properties:
  - type: AsyncAPI
    url: asyncapi/oddpool-feeds-asyncapi.yml
  - type: Webhooks
    url: asyncapi/oddpool-feeds-asyncapi.yml
  - type: Documentation
    url: https://docs.oddpool.com/websocket/overview.md
common:
- type: Website
  url: https://www.oddpool.com
- type: DeveloperPortal
  url: https://docs.oddpool.com
- type: Documentation
  url: https://docs.oddpool.com
- type: APIReference
  url: https://docs.oddpool.com/llms.txt
- type: GettingStarted
  url: https://docs.oddpool.com/index.md
- type: Pricing
  url: https://oddpool.com/pricing
- type: SignUp
  url: https://oddpool.com/sign-in
- type: TermsOfService
  url: https://oddpool.com/terms
- type: PrivacyPolicy
  url: https://oddpool.com/privacy
- type: Support
  url: https://cal.com/team/oddpool/30-minute-meeting
- type: LLMsTxt
  url: llms/oddpool-llms.txt
- type: Authentication
  url: authentication/oddpool-authentication.yml
- type: Conventions
  url: conventions/oddpool-conventions.yml
- type: ErrorCatalog
  url: errors/oddpool-problem-types.yml
- type: DataModel
  url: data-model/oddpool-data-model.yml
- type: Conformance
  url: conformance/oddpool-conformance.yml
- type: Lifecycle
  url: lifecycle/oddpool-lifecycle.yml
- type: X-MCPServerCandidate
  url: mcp/oddpool-mcp.yml
  note: 'Renamed from MCPServer 2026-09-03 (roadmap#247): the manifest self-describes as status: candidate — a tool list derived
    from the published API contracts, not an existing server. The scorer already read the manifest and reported mcp_server
    correctly; the MCPServer type was crediting the artifact-type surfaces with a server that does not exist.'
- type: AsyncAPI
  url: asyncapi/oddpool-feeds-asyncapi.yml
- type: Webhooks
  url: asyncapi/oddpool-feeds-asyncapi.yml
- type: DomainSecurity
  url: security/oddpool-domain-security.yml
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com
- FN: APIs.json
  email: info@apis.io
x-enrichment:
  date: '2026-07-20'
  status: enriched
  artifacts_added: 10
  pass: local-v1

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