Defined.ai (formerly DefinedCrowd) is an AI training data platform and marketplace founded in 2015 by Daniela Braga, headquartered in Seattle with offices in Lisbon, Porto, and Tokyo. It provides ready-to-use datasets across speech, text, image, video, and multimodal, plus custom data collection, annotation, machine translation, conversational AI, LLM fine-tuning, and data and model evaluation services sourced from a global community of 1.6M+ vetted contributors across 150+ markets and 500+ languages, dialects, and locales. The Defined.ai Public API (v2.0) lets enterprise customers manage projects programmatically — create Mean Opinion Score and Pronunciation Validation projects, upload input units, configure supported languages, track project status and errors, manage jobs, retrieve deliverables, and subscribe to notifications. Data provenance and compliance are backed by ISO 27001, ISO 27701, ISO 42001, GDPR, and HIPAA.
Defined.ai (DefinedCrowd) publishes 8 APIs on the APIs.io network, including Deliverables API, Input Units API, Jobs API, and 5 more. Tagged areas include Company, AI Training Data, Data Marketplace, Machine-Learning, and Data Annotation.
Defined.ai (DefinedCrowd)’s developer surface includes authentication, documentation, engineering blog, support, signup flow, and 16 more developer resources.
Create-or-Update Ergonomics applies to this provider. This API accepts writes, so it
carries 10 points of the composite. It is scored from the published contracts
themselves: whether a caller can create-or-update in one call, whether the write accepts a key the caller already
holds, and whether the response says which branch ran. Without that, every write needs a search-and-branch in
front of it, and the first time that check is skipped a duplicate record is created.
Scored against the observed mean rather than raw — a provider at the catalog average is unchanged by this facet,
not penalised by it.
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/definedcrowd: open an issue to ask a question, or submit a pull request to add artifacts.
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The result file is created after the project is completed and is referred to as deliverables. The file contains contributor metadata for completed input units.
Each input unit is a single component of work done by the contributors. There are several types of units – audio, text, and image. In a given project, all units should have the ...
Jobs are how your data (input units) connects the project with our contributors. Each job has data, instructions, and customizable parameters, which then convert inputs to outpu...
Informally, projects can be viewed as configurable packages that process sets of Input Units. The project’s template determines how the Input Units are processed. Projects can b...
Subscribe to automatic notifications for specific email addresses. Email notifications are sent for events that happen during the life cycle of the project. By using thi...
Several of the Workflow Templates offer the ability to set a language / country code. These configurations instruct Defined.ai to use our human intelligence Contributors that sp...
aid: definedcrowd
name: Defined.ai (DefinedCrowd)
description: Defined.ai (formerly DefinedCrowd) is an AI training data platform and marketplace founded in 2015 by Daniela
Braga, headquartered in Seattle with offices in Lisbon, Porto, and Tokyo. It provides ready-to-use datasets across speech,
text, image, video, and multimodal, plus custom data collection, annotation, machine translation, conversational AI, LLM
fine-tuning, and data and model evaluation services sourced from a global community of 1.6M+ vetted contributors across
150+ markets and 500+ languages, dialects, and locales. The Defined.ai Public API (v2.0) lets enterprise customers manage
projects programmatically — create Mean Opinion Score and Pronunciation Validation projects, upload input units, configure
supported languages, track project status and errors, manage jobs, retrieve deliverables, and subscribe to notifications.
Data provenance and compliance are backed by ISO 27001, ISO 27701, ISO 42001, GDPR, and HIPAA.
url: https://raw.githubusercontent.com/api-evangelist/definedcrowd/refs/heads/main/apis.yml
x-type: company
x-source: vc-portfolio
x-backed-by:
- balderton-capital
x-tier: profiled
x-tier-reason: enriched-from-public-api
deliveryModel:
model: saas
open_source: false
commercial: true
callable_host: true
label: Hosted service · you call their endpoint
confidence: high
source:
- openapi
- 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
- url: https://www.definedcrowd.com/
status: 302
note: declared website redirects to https://defined.ai/ — a different registrable domain (definedcrowd.com -> defined.ai),
possible rename or acquisition (probed 2026-09-03, roadmap#169)
generated: '2026-09-03'
method: derived
specificationVersion: '0.23'
created: '2026-07-17'
modified: '2026-07-18'
image: https://defined.ai/favicon.ico
tags:
- Company
- AI Training Data
- Data Marketplace
- Machine-Learning
- Data Annotation
- Speech Data
- Natural Language Processing
- Crowdsourcing
- Artificial Intelligence
tags_raw:
- Company
- AI Training Data
- Data Marketplace
- Machine Learning
- Data Annotation
- Speech Data
- Natural Language Processing
- Crowdsourcing
- Artificial Intelligence
apis:
- aid: definedcrowd:definedcrowd-deliverables-api
name: Defined.ai (DefinedCrowd) Deliverables API
description: The result file is created after the project is completed and is referred to as deliverables. The file contains
contributor metadata for completed input units.
humanURL: https://developers.definedcrowd.com/
baseURL: https://api.production-na01.definedcrowd.com
tags:
- Deliverables
properties:
- type: OpenAPI
url: openapi/definedcrowd-deliverables-api-openapi.yml
- type: APIReference
url: https://developers.definedcrowd.com/
- aid: definedcrowd:definedcrowd-input-units-api
name: Defined.ai (DefinedCrowd) Input Units API
description: "Each input unit is a single component of work done by the contributors. There are several types of units –\
\ audio, text, and image. In a given project, all units should have the same structure. The input unit schema explains\
\ the structure of input units. \n\n Note: Input Units are a part of projects. They are not separate entities."
humanURL: https://developers.definedcrowd.com/
baseURL: https://api.production-na01.definedcrowd.com
tags:
- Input Units
properties:
- type: OpenAPI
url: openapi/definedcrowd-input-units-api-openapi.yml
- type: APIReference
url: https://developers.definedcrowd.com/
- aid: definedcrowd:definedcrowd-jobs-api
name: Defined.ai (DefinedCrowd) Jobs API
description: Jobs are how your data (input units) connects the project with our contributors. Each job has data, instructions,
and customizable parameters, which then convert inputs to outputs. Parameters are customizable according to your project
needs.
humanURL: https://developers.definedcrowd.com/
baseURL: https://api.production-na01.definedcrowd.com
tags:
- Job
tags_raw:
- Jobs
properties:
- type: OpenAPI
url: openapi/definedcrowd-jobs-api-openapi.yml
- type: APIReference
url: https://developers.definedcrowd.com/
- aid: definedcrowd:definedcrowd-mean-opinion-score-api
name: Defined.ai (DefinedCrowd) Mean Opinion Score API
description: Aggregate ratings on the "intelligibility" and "naturalness" of utterances.
humanURL: https://developers.definedcrowd.com/
baseURL: https://api.production-na01.definedcrowd.com
tags:
- Mean Opinion Score
properties:
- type: OpenAPI
url: openapi/definedcrowd-mean-opinion-score-api-openapi.yml
- type: APIReference
url: https://developers.definedcrowd.com/
- aid: definedcrowd:definedcrowd-project-management-api
name: Defined.ai (DefinedCrowd) Project Management API
description: 'Informally, projects can be viewed as configurable packages that process sets of Input Units. The project’s
template determines how the Input Units are processed. Projects can be retrieved and managed as needed through the following
methods:'
humanURL: https://developers.definedcrowd.com/
baseURL: https://api.production-na01.definedcrowd.com
tags:
- Project Management
properties:
- type: OpenAPI
url: openapi/definedcrowd-project-management-api-openapi.yml
- type: APIReference
url: https://developers.definedcrowd.com/
- aid: definedcrowd:definedcrowd-pronunciation-validation-api
name: Defined.ai (DefinedCrowd) Pronunciation Validation API
description: Confirm audio meets pronunciation standards.
humanURL: https://developers.definedcrowd.com/
baseURL: https://api.production-na01.definedcrowd.com
tags:
- Pronunciation Validation
properties:
- type: OpenAPI
url: openapi/definedcrowd-pronunciation-validation-api-openapi.yml
- type: APIReference
url: https://developers.definedcrowd.com/
- aid: definedcrowd:definedcrowd-subscriptions-api
name: Defined.ai (DefinedCrowd) Subscriptions API
description: "Subscribe to automatic notifications for specific email addresses. Email notifications are sent for events\
\ that happen during the life cycle of the project.\n\n <small> By using this service, the user fully agrees with Defined.ai's\
\ service <a href=\"https://www.defined.ai/terms-of-use/\">Terms\nof Use</a>, and acknowledges and understands that any\
\ processing of personal data will be carried out according to the terms of Defined.ai's <a href=\"https://www.defined.ai/privacy-policy/\"\
>Privacy Policy</a>. The user further acknowledges that it is fully responsible for obtaining and managing all necessary\
\ valid consents from all data subjects whose email address is being subscribed by the user, for the sole purposes of\
\ receiving service notifications in context of Defined.ai provided services, in compliance with all applicable data protection\
\ laws, including the EU General Data Protection Regulation (GDPR) and the California Consumer Privacy Act (CCPA). The\
\ user also acknowledges that it is fully responsible for unsubscribing such emails once no longer necessary for these\
\ purposes or in case the data subject has removed its consent.\n\n Defined.ai reserves the right to proceed with the\
\ immediate service suspension without any prior\nnotice, if it detects service abuse, non-compliance with the above obligations\
\ or in case it receives complaints from data subjects that have not provided their consent for the subscription of their\
\ email. </small>"
humanURL: https://developers.definedcrowd.com/
baseURL: https://api.production-na01.definedcrowd.com
tags:
- Subscription
tags_raw:
- Subscriptions
properties:
- type: OpenAPI
url: openapi/definedcrowd-subscriptions-api-openapi.yml
- type: APIReference
url: https://developers.definedcrowd.com/
- aid: definedcrowd:definedcrowd-supported-languages-api
name: Defined.ai (DefinedCrowd) Supported Languages API
description: Several of the Workflow Templates offer the ability to set a language / country code. These configurations
instruct Defined.ai to use our human intelligence Contributors that speak and / or reside in the specified language /
country. The REST API provides a method called “Get Supported Languages” that returns the set of languages, language features
and associated language codes that are used by our APIs and supported by the Defined.ai platform.
humanURL: https://developers.definedcrowd.com/
baseURL: https://api.production-na01.definedcrowd.com
tags:
- Supported Languages
properties:
- type: OpenAPI
url: openapi/definedcrowd-supported-languages-api-openapi.yml
- type: APIReference
url: https://developers.definedcrowd.com/
maintainers:
- FN: Kin Lane
email: kin@apievangelist.com
- FN: APIs.json
email: info@apis.io
common:
- type: DomainSecurity
url: security/definedcrowd-domain-security.yml
- type: AgenticAccess
url: agentic-access/definedcrowd-agentic-access.yml
- type: Authentication
url: authentication/definedcrowd-authentication.yml
- type: Website
url: https://www.definedcrowd.com/
- type: DeveloperPortal
url: https://developers.definedcrowd.com/
- type: Documentation
url: https://developers.definedcrowd.com/
- type: Blog
url: https://defined.ai/blog
- type: Support
url: https://defined.ai/contact-us
- type: TermsOfService
url: https://defined.ai/terms-of-use
- type: PrivacyPolicy
url: https://defined.ai/privacy-policy
- type: SignUp
url: https://enterprise.definedcrowd.com
- type: LLMsTxt
url: https://defined.ai/llms.txt
- type: ErrorCatalog
url: errors/definedcrowd-problem-types.yml
- type: Conventions
url: conventions/definedcrowd-conventions.yml
- type: DataModel
url: data-model/definedcrowd-data-model.yml
- type: X-MCPServerCandidate
url: mcp/definedcrowd-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: Overlay
url: overlays/definedcrowd-openapi-overlay.yaml
- type: Conformance
url: conformance/definedcrowd-conformance.yml
- type: Compliance
url: https://defined.ai/about-us
- type: Lifecycle
url: lifecycle/definedcrowd-lifecycle.yml
- type: AgentSkill
url: skills/_index.yml
x-enrichment:
date: '2026-07-19'
status: backfilled
pass: local-v1
note: backfilled from .gitignore signal + verified work evidence
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