Open Trivia Database
The Open Trivia Database (OpenTDB) is a free, user-contributed trivia question database operated by Pixeltail Games LLC. It offers a JSON REST API for retrieving thousands of community-verified trivia questions across 24 categories and three difficulty levels, with optional session tokens to prevent duplicate questions. The service is licensed Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0), is free at the point of use, and enforces a single throttling rule: one request per IP every five seconds.
Real signal across most facets with visible, nameable gaps — the contract exists but is thin, or the portal is good while governance and commercial terms are absent.
API Evangelist profiles Open Trivia Database the way a machine reads it — 38 machine-readable artifacts across 4 APIs, pulled from the provider's own public surface and indexed so a developer, an analyst, or an AI agent can evaluate it against every other provider on the network.
Every provider in the network is reduced to the same set of machine-readable artifacts — OpenAPI contracts, event specifications, GraphQL schemas, runnable collections, pricing and rate-limit signals, security posture, OAuth scopes, and the agent surfaces (MCP servers and skills) that let software drive the API on its own. We profile them because the interface is the part of a company you can actually inspect: it is a truer signal of what a provider does than any marketing page. From those artifacts we compute the Kin Score — Open Trivia Database scores 45.1/100 (developing), with a separate agent-readiness read of 45/100 (agent ready). The full breakdown is below, followed by every artifact we hold — each card links through to its machine-readable definition on apis.io.
Kin Score
This is the API Evangelist rating — a single, repeatable read computed from the artifacts on this page. Green fill is points earned; the red track is points possible, so every bar shows earned-versus-possible at a glance.
Kin Score
How this is scored →scored 2026-07-27 · rubric v0.5
How we profile Open Trivia Database
Each block below is one kind of artifact we hold for Open Trivia Database. For each we say what it is and why it earns a place in the profile, then list every one we've indexed — capped at two rows, scroll within the panel for the rest.
APIs 4
Each API is captured as its own OpenAPI definition — every operation, parameter, and response. This is the single most useful machine-readable description of what an API does, and it's what lets us score, lint, mock, and generate against it without asking the provider for anything.
Individual APIs this provider publishes, each with its own machine-readable definition.
Open Trivia Database Categories API
Operations for discovering trivia category metadata and counts.
Open Trivia Database Questions API
Operations for retrieving trivia questions from the database.
Open Trivia Database Statistics API
Operations for inspecting overall database statistics.
Open Trivia Database Tokens API
Operations for managing session tokens that prevent duplicate questions.
Open Collections 1
Open, tool-agnostic collections carry the same runnable value as Postman without locking you to one client — the portable, forkable form of the same exercise.
Open, tool-agnostic API collections (OpenAPI-derived and Bruno).
Open Trivia Database API
OPEN COLLECTIONRate Limits 1
Rate limits are the difference between a demo that works and a production integration that doesn't fall over. Publishing them is an operational-transparency signal — and a hard requirement for any agent that plans its own throughput.
Documented rate limits and quota policies.
Open Trivia Rate Limits
RATE LIMITSSemantic Vocabularies 1
JSON-LD contexts give the data shared meaning across APIs. We profile them because semantics are what let a machine reconcile 'customer' here with 'customer' somewhere else.
JSON-LD contexts and semantic vocabularies used across these APIs.
Open Trivia Context
JSON-LDSpectral Rules 2
Governance rulesets we run against this provider's specs — the automated checks behind parts of the score. Profiling them makes the quality bar explicit and re-runnable, not a matter of opinion.
Open Trivia Database API Rules
SPECTRALOpen Trivia Database API Rules
SPECTRALJSON Schema 9
Standalone JSON Schema definitions describe the data models behind the API. We profile them so the shapes are validatable on their own — useful long after a single request is forgotten.
Standalone JSON Schema definitions for this provider's data models.
CategoryCountResponse
JSON SCHEMACategoryListResponse
JSON SCHEMACategoryQuestionCount
JSON SCHEMACategory
JSON SCHEMAGlobalCountResponse
JSON SCHEMAGlobalCounts
JSON SCHEMAQuestionResponse
JSON SCHEMAQuestion
JSON SCHEMATokenResponse
JSON SCHEMAScroll within the panel for all 9 ·
JSON Structure 9
JSON Structure captures the data shapes in a form built for tooling — a complement to JSON Schema that keeps the model machine-legible.
JSON Structure definitions describing this provider's data shapes.
Open Trivia Category Count Response Structure
JSON STRUCTUREOpen Trivia Category List Response Structure
JSON STRUCTUREOpen Trivia Category Question Count Structure
JSON STRUCTUREOpen Trivia Category Structure
JSON STRUCTUREOpen Trivia Global Count Response Structure
JSON STRUCTUREOpen Trivia Global Counts Structure
JSON STRUCTUREOpen Trivia Question Response Structure
JSON STRUCTUREOpen Trivia Question Structure
JSON STRUCTUREOpen Trivia Token Response Structure
JSON STRUCTUREScroll within the panel for all 9 ·
Examples 9
Real request and response payloads are what turn a spec from abstract into obvious — and they're one of the twelve things an agent needs to call an API correctly on the first try.
Example request and response payloads for these APIs.
Open Trivia Category Example
EXAMPLEOpen Trivia Question Example
EXAMPLEScroll within the panel for all 9 ·
Security Posture 1
Authentication, domain security, vulnerability disclosure, and trust-center signals — the evidence that a provider takes security seriously enough to document it. We profile it because you can't govern what you can't see.
Authentication, domain security, vulnerability disclosure, and trust-center signals.
Agentic Access 1
An x-agentic-access contract marks which operations are safe for an agent to run on its own and which need a human in the loop. It is the difference between an API an agent can use and one it can use safely.
Recommended x-agentic-access execution contracts for AI agents.
Resources
Every other property we hold for Open Trivia Database — documentation, portals, status pages, policies, and corporate surface — grouped by the job it does, following the integrator's arc from getting started to running in production.
Documentation 1
Reference material describing how the API behaves
Agent Surfaces 1
MCP servers, agent skills, and machine-readable catalogs
Build 11
SDKs, sample code, and the tooling you integrate with
Scroll within the panel for all 11 ·
Access & Security 1
Authentication, authorization, and security posture
Operate 1
Status, limits, changes, and where to get help
Commercial 2
Pricing, plans, and the legal terms of use
Company 1
The organization behind the API
Other 2
Properties that don't map to a standard resource type
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