WeFitter is a health and fitness data platform ("one API to access wearable data, gamification and AI") operated by Thunderbyte.AI in Groningen, Netherlands. Its REST API aggregates health and activity data from 300+ wearables and fitness apps — Fitbit, Garmin, Google Fit, Apple Health, Withings, Polar, Oura, Whoop, Samsung Health, Huawei and more — into a single unified, deduplicated data model, and layers gamification (challenges, leaderboards, teams, points) and AI insights (biological age, recommendations) on top. Organizations use it to build corporate wellbeing, digital fitness, e-health and insurance solutions. WeFitter also ships mobile SDK bridges for Apple Health, Samsung Health and Android Health Connect.
WeFitter publishes 9 API contracts indexed on the APIs.io network, including App API, Challenge API, Connection API, and 6 more. Tagged areas include Company, Health, Fitness, Wearables, and Health Data.
The WeFitter catalog on APIs.io includes 1 event-driven AsyncAPI specification and 1 Spectral governance ruleset.
WeFitter’s developer surface includes documentation, getting-started guide, API reference, support, engineering blog, changelog, signup flow, and 25 more developer resources.
Regulatory Posture applies to this provider. Its tags matched the
Health regime, so
Regulatory Posture carries 15 points of the composite.
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provider repo — the
applicability map is public and we will correct it.
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.
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Agent readiness — checks not met, largest first (exact, from this profile):
MCP Server+12 pts — deployment.mode + probe verdict on the mcp/ manifest, not the pointer; an unprobed slug falls back to authorship
Idempotency+9 pts — OpenAPI mutating operations declare an idempotency key — a header, a request-body property, or a named de-duplication token whose own description says so (verified); else common[].type matches /idempoten/i (documented)
A2A Agent Card+8 pts — a2a/-a2a.yml manifest, graded on conformance.grade against A2A 1.0.0
Rate-Limit Signaling+7 pts — OpenAPI responses document X-RateLimit-* / RateLimit headers (verified), else a rate_limits artifact or RateLimits link (documented)
Request/Response Examples+7 pts — share of operations carrying request/response examples; else an Examples / Code Samples link
The Kin Score Market layer reads a provider inside its market:
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Standards this provider implements or carries. De facto ones are profiled and measured by the API Commons; formal ones come from the standards directory and are linked by the provider's own tags. The evidence column says how each claim was established — not that it was made.
WeFitter API’s challenge engine will bring endless engagement to your platform. For more information about the possibilities in challenges please go to https://www.wefitter.com/...
Send a notification to all devices for the specified profiles The data will be sent to the client in the following format: ``` { "app": , "title": , "body": , "link": <opti
Profiles are containers for wearables data. The profiles can be seen as an extension of users in a different system. Profiles are anonymous objects which can participate in team...
Before any calls can be made to wefitter, BasicAuth is needed to verify the identity of the requesting party. This call will result into a Bearer token which has administrator ...
Overlays applied on top of this provider's contracts. Each card says who wrote it: a document the provider publishes, or one API Evangelist derived or generated.
x-enrichment:
date: '2026-07-21'
status: enriched
artifacts_added: 16
pass: local-v1
aid: wefitter
name: WeFitter
description: WeFitter is a health and fitness data platform ("one API to access wearable data, gamification and AI") operated
by Thunderbyte.AI in Groningen, Netherlands. Its REST API aggregates health and activity data from 300+ wearables and fitness
apps — Fitbit, Garmin, Google Fit, Apple Health, Withings, Polar, Oura, Whoop, Samsung Health, Huawei and more — into a
single unified, deduplicated data model, and layers gamification (challenges, leaderboards, teams, points) and AI insights
(biological age, recommendations) on top. Organizations use it to build corporate wellbeing, digital fitness, e-health and
insurance solutions. WeFitter also ships mobile SDK bridges for Apple Health, Samsung Health and Android Health Connect.
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
generated: '2026-11-06'
method: derived
image: https://www.wefitter.com/static/frontend/img/website/wefitter.png
url: https://raw.githubusercontent.com/api-evangelist/wefitter/refs/heads/main/apis.yml
x-type: company
x-source: vc-portfolio
x-backed-by:
- 500-global
x-operator: Thunderbyte.AI
specificationVersion: '0.23'
created: '2026-07-17'
modified: '2026-07-21'
tags:
- Company
- Health
- Fitness
- Wearables
- Health Data
- Wellbeing
- Gamification
- Digital Health
- Insurance
- Activity Tracking
apis:
- aid: wefitter:wefitter-app-api
name: WeFitter App API
description: The app API from WeFitter — 1 operation(s) for app.
humanURL: https://www.wefitter.com/en-us/developers/
baseURL: https://api.wefitter.com/api/v1.3
tags:
- App
tags_raw:
- app
properties:
- type: OpenAPI
url: openapi/wefitter-app-api-openapi.yml
- type: Swagger
url: https://api.wefitter.com/api/v1.3/redoc/?format=openapi
- type: APIReference
url: https://api.wefitter.com/api/v1.3/redoc/
- aid: wefitter:wefitter-challenge-api
name: WeFitter Challenge API
description: "WeFitter API’s challenge engine will bring endless engagement to your platform.\nFor more information about\
\ the possibilities in challenges please go to https://www.wefitter.com/en-us/features/gamification/\n\nChallenges have\
\ multilanguage support on the fields: `Title`, `Slogan`, and `Description`.\nBy default, challenges get the default-language\
\ that is configured in the app. Whenever a challenge is requested through the API this challenge will be presented in\
\ the default language.\nIf another language is preferred, this can be requested by adding the header parameter `Accept-Language`\
\ stating the language short code (ex. `en` for english). If this language short code is not present in the title of the\
\ challenge, the default language will be returned.\n\nThese translation fields contain JSON strings, for example:\n```{\"\
en\":\"this is the English title\",\"nl\":\"this is the Dutch title\"}```\nSo to create a multilanguage challenge, please\
\ provide the title, slogan, and description field as json strings, be aware that because of serialization this should\
\ be formed with backward slashes:\n\n\n<table><tbody>\n <tr><td>\n{\n\n\"title\": \"{\\\"en\\\":\\\"this is the English\
\ title\\\", \\\"nl\\\":\\\"this is the dutch title\\\"}\",\n\n\"slogan\": \"{\\\"en\\\":\\\"this is the English title\\\
\", \\\"nl\\\":\\\"this is the dutch slogan\\\"}\",\n\n\"description\": \"{\\\"en\\\":\\\"this is the English title\\\"\
, \\\"nl\\\":\\\"this is the dutch description\\\"}\",\n\n}\n</td></tr>\n</tbody></table>"
humanURL: https://www.wefitter.com/en-us/developers/
baseURL: https://api.wefitter.com/api/v1.3
tags:
- Challenge
tags_raw:
- challenge
properties:
- type: OpenAPI
url: openapi/wefitter-challenge-api-openapi.yml
- type: Swagger
url: https://api.wefitter.com/api/v1.3/redoc/?format=openapi
- type: APIReference
url: https://api.wefitter.com/api/v1.3/redoc/
- aid: wefitter:wefitter-connection-api
name: WeFitter Connection API
description: Connections are the links between profiles and their wearables.
humanURL: https://www.wefitter.com/en-us/developers/
baseURL: https://api.wefitter.com/api/v1.3
tags:
- Connection
tags_raw:
- connection
properties:
- type: OpenAPI
url: openapi/wefitter-connection-api-openapi.yml
- type: Swagger
url: https://api.wefitter.com/api/v1.3/redoc/?format=openapi
- type: APIReference
url: https://api.wefitter.com/api/v1.3/redoc/
- aid: wefitter:wefitter-insights-api
name: WeFitter Insights API
description: The insights API from WeFitter — 1 operation(s) for insights.
humanURL: https://www.wefitter.com/en-us/developers/
baseURL: https://api.wefitter.com/api/v1.3
tags:
- Insights
tags_raw:
- insights
properties:
- type: OpenAPI
url: openapi/wefitter-insights-api-openapi.yml
- type: Swagger
url: https://api.wefitter.com/api/v1.3/redoc/?format=openapi
- type: APIReference
url: https://api.wefitter.com/api/v1.3/redoc/
- aid: wefitter:wefitter-loyalty-api
name: WeFitter Loyalty API
description: The loyalty API from WeFitter — 2 operation(s) for loyalty.
humanURL: https://www.wefitter.com/en-us/developers/
baseURL: https://api.wefitter.com/api/v1.3
tags:
- Loyalty
tags_raw:
- loyalty
properties:
- type: OpenAPI
url: openapi/wefitter-loyalty-api-openapi.yml
- type: Swagger
url: https://api.wefitter.com/api/v1.3/redoc/?format=openapi
- type: APIReference
url: https://api.wefitter.com/api/v1.3/redoc/
- aid: wefitter:wefitter-notification-api
name: WeFitter Notification API
description: "Send a notification to all devices for the specified profiles\nThe data will be sent to the client in the\
\ following format:\n```\n{\n \"app\": <app public id>,\n \"title\": <title>,\n \"body\": <body>,\n\
\ \"link\": <optional link>\n}\n```"
humanURL: https://www.wefitter.com/en-us/developers/
baseURL: https://api.wefitter.com/api/v1.3
tags:
- Notification
tags_raw:
- notification
properties:
- type: OpenAPI
url: openapi/wefitter-notification-api-openapi.yml
- type: Swagger
url: https://api.wefitter.com/api/v1.3/redoc/?format=openapi
- type: APIReference
url: https://api.wefitter.com/api/v1.3/redoc/
- aid: wefitter:wefitter-profile-api
name: WeFitter Profile API
description: 'Profiles are containers for wearables data.
The profiles can be seen as an extension of users in a different system.
Profiles are anonymous objects which can participate in teams and challenges.
Keep in mind, listing profiles and creating profiles need an administrative bearer token, all profile specific actions
need a seperate bearer token that is returned after creating a profile. This bearer token is used in place of the
administrative bearer token. (see profile create action for more information)'
humanURL: https://www.wefitter.com/en-us/developers/
baseURL: https://api.wefitter.com/api/v1.3
tags:
- Profiles
tags_raw:
- profile
properties:
- type: OpenAPI
url: openapi/wefitter-profile-api-openapi.yml
- type: Swagger
url: https://api.wefitter.com/api/v1.3/redoc/?format=openapi
- type: APIReference
url: https://api.wefitter.com/api/v1.3/redoc/
- aid: wefitter:wefitter-team-api
name: WeFitter Team API
description: The team API from WeFitter — 5 operation(s) for team.
humanURL: https://www.wefitter.com/en-us/developers/
baseURL: https://api.wefitter.com/api/v1.3
tags:
- Team
tags_raw:
- team
properties:
- type: OpenAPI
url: openapi/wefitter-team-api-openapi.yml
- type: Swagger
url: https://api.wefitter.com/api/v1.3/redoc/?format=openapi
- type: APIReference
url: https://api.wefitter.com/api/v1.3/redoc/
- aid: wefitter:wefitter-token-api
name: WeFitter Token API
description: '<p>
Before any calls can be made to wefitter, BasicAuth is needed to verify the identity of the requesting party.
This call will result into a Bearer token which has administrator privileges and is valid for 1 day.
This token can be used to create profiles, challenges, etc.
</p>
<p>
The returned bearer is a JWT (<a href="https://en.wikipedia.org/wiki/JSON_Web_Token">JSON Web Token</a>).
</p>'
humanURL: https://www.wefitter.com/en-us/developers/
baseURL: https://api.wefitter.com/api/v1.3
tags:
- Tokens
tags_raw:
- token
properties:
- type: OpenAPI
url: openapi/wefitter-token-api-openapi.yml
- type: Swagger
url: https://api.wefitter.com/api/v1.3/redoc/?format=openapi
- type: APIReference
url: https://api.wefitter.com/api/v1.3/redoc/
maintainers:
- FN: Kin Lane
email: kin@apievangelist.com
- FN: APIs.json
email: info@apis.io
common:
- type: CapabilityMap
url: capabilities/wefitter-capability-edges.yml
name: WeFitter Business Capability Map
- type: DeveloperPortal
url: https://www.wefitter.com/en-us/developers/
- type: Documentation
url: https://www.wefitter.com/en-us/developers/documentation/
- type: GettingStarted
url: https://www.wefitter.com/en-us/developers/getting-started/
- type: APIReference
url: https://api.wefitter.com/api/v1.3/redoc/
- type: Guides
url: https://www.wefitter.com/en-us/developers/guides/
- type: Support
url: https://developers.wefitter.com/support
- type: Blog
url: https://www.wefitter.com/en-us/resources/blog/
- type: ChangeLog
url: https://www.wefitter.com/en-us/developers/changelog/
- type: GitHubOrganization
url: https://github.com/wefitter
- type: SignUp
url: https://api.wefitter.com/dashboard
- type: TermsOfService
url: https://www.wefitter.com/en-us/terms-and-conditions/
- type: PrivacyPolicy
url: https://www.wefitter.com/en-us/privacy-policy/
- type: OpenAPI
url: openapi/_original/wefitter-openapi-original.json
- type: Overlay
url: overlays/wefitter-openapi-overlay.yaml
- type: Packages
url: packages/wefitter-packages.yml
- type: SDKs
url: packages/wefitter-packages.yml
- type: X-MCPServerCandidate
url: mcp/wefitter-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: LLMsTxt
url: llms/wefitter-llms.txt
- type: Conformance
url: conformance/wefitter-conformance.yml
- type: ErrorCatalog
url: errors/wefitter-problem-types.yml
- type: Lifecycle
url: lifecycle/wefitter-lifecycle.yml
- type: ChangeLog
url: changelog/wefitter-changelog.yml
- type: Conventions
url: conventions/wefitter-conventions.yml
- type: DataModel
url: data-model/wefitter-data-model.yml
- type: Webhooks
url: asyncapi/wefitter-webhooks.yml
- type: Components
url: components/wefitter-components.yml
- type: AgentSkill
url: skills/_index.yml
- type: DomainSecurity
url: security/wefitter-domain-security.yml
- type: AgenticAccess
url: agentic-access/wefitter-agentic-access.yml
- type: Authentication
url: authentication/wefitter-authentication.yml
- type: Website
url: https://wefitter.com
WeFitter API — frequently asked questions
Does WeFitter have an API?
Yes. APIs.io lists 9 APIs from WeFitter, including WeFitter App API, WeFitter Challenge API and WeFitter Connection API, and 6 more.
Is there an OpenAPI specification for the WeFitter API?
Yes. APIs.io indexes 9 OpenAPI specifications for WeFitter, each linked for download from this page.
How do I authenticate with the WeFitter API?
WeFitter uses bearer-token authentication (apiKey/http · 2 schemes). The details are profiled on APIs.io as Wefitter Authentication.
Is the WeFitter API ready for AI agents?
WeFitter has a Kin Score of 48.1 out of 100 (developing) and an Agent Readiness score of 25.3 (agent-aware), scored by API Evangelist on 2026-11-06.
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