Fanbridge

FanBridge was an email and SMS marketing platform for musicians, artists, bands, and creators, letting them grow and message their fan mailing lists, run newsletters, and capture subscribers from shows and social channels. It was surfaced as a portfolio company of 500 Global and added to the API Evangelist network as a stub. Enrichment (2026-07-19) confirmed FanBridge is defunct - it was acquired by Kit (formerly ConvertKit) and ceased operations on April 11, 2022, with active accounts migrated to the Kit platform. The domain fanbridge.com now 302-redirects to kit.com/fanbridge. There is no standalone FanBridge developer API, documentation, SDK, or event surface; the developer docs linked from the destination site belong to Kit, not FanBridge.

Fanbridge is profiled on the APIs.io network. Tagged areas include Company, Email Marketing, SMS Marketing, Music, and Musicians.

🌐 Visit website 📡 Profile data on GitHub

0.0/100 minimal ▬ flat Agent 0/100 human only Front door AI 1/6 silent Full breakdown ↓
scored 2026-11-06 · rubric v0.27.0 · Show this score on your site →

0 APIs 1 MCP Servers

Company Email Marketing SMS Marketing MusicMusiciansFan Engagement Marketing Newsletters Defunct

Kin Score

Kin Score How this is scored →
scored 2026-11-06 · rubric v0.27.0

Composite quality — 0.0/100 · minimal

Contract Quality 0.0 / 21

Developer Ergonomics 0.0 / 17

Access Clarity 0.0 / 17

Operational Transparency 0.0 / 11

Contract Governance 0.0 / 10

Discoverability 0.0 / 9

Regulatory Posture 0.0 / 15

Agent readiness — 0/100 · human only

Machine-Readable Contract 0 / 18

Agentic Access Contract 0 / 10

Documented Reversibility 0 / 6

MCP Server 12 / 12

Machine-Readable Auth 0 / 10

Idempotency 0 / 9

Stable Error Semantics 0 / 8

Request/Response Examples 0 / 7

Rate-Limit Signaling 0 / 7

Typed Event Surface 0 / 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 5 / 5

Registration Without a Human 0 / 6

Agentic Commerce Well-Known Document 0 / 5

Pagination 5 / 5

Distinct Operations 3 / 3

MCP Tool Quality 6 / 6

Regulatory Posture applies to this provider. Its tags matched the Horizontal (data, software, accessibility, platform) 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/.

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<a href="https://apis.io/providers/fanbridge/"><img src="https://apis.io/badge/fanbridge/card.svg" alt="Fanbridge on APIs.io — Kin Score by API Evangelist"></a>

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Agent readiness — checks not met, largest first (exact, from this profile):

Machine-Readable Contract +18 pts — api_specs includes an OpenAPI document
Agentic Access Contract +10 pts — agentic_access artifact present (x-agentic-access), graded by author
Machine-Readable Auth +10 pts — a served openid-configuration/oauth-authorization-server carrying `issuer` (served), else the securitySchemes class in the provider OpenAPIs — bound (mutualTLS, DPoP, Signature) > negotiable (oauth2 authorizationCode/clientCredentials, openIdConnect) > bearer (http bearer, apiKey)
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)
Stable Error Semantics +8 pts — OpenAPI $refs a shared error schema across 4xx/5xx responses (verified), else common[].type includes ErrorCatalog / ErrorCodes / DeclineCodes
A2A Agent Card +8 pts — a2a/-a2a.yml manifest, graded on conformance.grade against A2A 1.0.0

11 more unmet checks in the Agent Readiness table above.

Kin Score — facets with the most composite points still available (weight × headroom):

Contract Quality scores 0.0 — up to +25.0 composite points
Developer Ergonomics scores 0.0 — up to +20.0 composite points
Access Clarity scores 0.0 — up to +20.0 composite points

Each check links to what satisfies it. Publish the artifact, or tell us where it already lives, and the score moves on the next scoring run.

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 the provider profile at artifacts.apis.io/fanbridge/apis.yml: open an issue on github.com/api-evangelist/fanbridge to ask a question or point us at an artifact you publish. Submit an artifact on GitHub — free → Manage your own listing — the Influence plan, $499/mo →

Standards implemented 2

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.

Model Context Protocol (MCP)

measured — observed by APIs.io (verified)

OAuth 2.0 Protected Resource Metadata

measured — observed by APIs.io (verified)

MCP Servers 1

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

Fanbridge MCP Server

Remote MCP server at api.kit.com over HTTP.

MCP SERVER

Resources

Company 2

The organization behind the API

Website

Website

SuccessorWebsite

SuccessorWebsite

Source (apis.yml)

aid: fanbridge
deliveryModel:
  model: unknown
  open_source: false
  commercial: false
  callable_host: false
  label: Delivery model not determined — needs a product licence on record
  confidence: low
  source:
  - none
  generated: '2026-08-28'
  method: derived
accessModel:
  pricing: unknown
  onboarding: unknown
  trial: false
  try_now: false
  public: false
  label: Unknown
  confidence: low
  source: []
  generated: '2026-11-06'
  method: derived
image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/icons/fanbridge.png
name: Fanbridge
description: FanBridge was an email and SMS marketing platform for musicians, artists, bands, and creators, letting them grow
  and message their fan mailing lists, run newsletters, and capture subscribers from shows and social channels. It was surfaced
  as a portfolio company of 500 Global and added to the API Evangelist network as a stub. Enrichment (2026-07-19) confirmed
  FanBridge is defunct - it was acquired by Kit (formerly ConvertKit) and ceased operations on April 11, 2022, with active
  accounts migrated to the Kit platform. The domain fanbridge.com now 302-redirects to kit.com/fanbridge. There is no standalone
  FanBridge developer API, documentation, SDK, or event surface; the developer docs linked from the destination site belong
  to Kit, not FanBridge.
url: https://raw.githubusercontent.com/api-evangelist/fanbridge/refs/heads/main/apis.yml
x-type: company
x-source: vc-portfolio
x-backed-by:
- 500-global
x-tier: stub
x-tier-reason: portfolio-lead
x-status: defunct
x-status-detail: Acquired by Kit (formerly ConvertKit); ceased operations 2022-04-11; accounts migrated to Kit; fanbridge.com
  redirects to kit.com/fanbridge.
x-acquired-by: kit
x-shutdown-date: '2022-04-11'
x-redirects-to: https://kit.com/fanbridge
x-enrichment-note: No API/OpenAPI/docs/SDK/MCP/event surface exists - provider is defunct. Enrichment verified via live redirect
  probe (fanbridge.com -> 302 -> kit.com/fanbridge) and page fetch on 2026-07-19.
specificationVersion: '0.23'
created: '2026-07-17'
modified: '2026-09-15'
tags:
- Company
- Email Marketing
- SMS Marketing
- Music
- Musicians
- Fan Engagement
- Marketing
- Newsletters
- Defunct
apis: []
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com
- FN: APIs.json
  email: info@apis.io
common:
- type: Website
  url: https://fanbridge.com
- type: SuccessorWebsite
  name: Kit (formerly ConvertKit) - FanBridge successor
  url: https://kit.com/fanbridge
x-enrichment:
  date: '2026-07-19'
  status: backfilled
  pass: local-v1
  note: backfilled from .gitignore signal + verified work evidence

Fanbridge API — frequently asked questions

Does Fanbridge have an MCP server?

Yes. APIs.io lists 1 MCP server for Fanbridge: Remote MCP server at api.kit.com over HTTP.

Is the Fanbridge API ready for AI agents?

Fanbridge has a Kin Score of 0.0 out of 100 (minimal) and an Agent Readiness score of 0.0 (human-only), scored by API Evangelist on 2026-11-06.

Work with this as data

Every provider here is available over the APIs.io API and to AI agents over MCP.

MCP server

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Tools for providers

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get_provider_artifactsEvery artifact this provider publishes, grouped by type.
get_provider_operationsEvery operation across all of their OpenAPIs — one call instead of parsing every spec.
get_provider_toolsEvery MCP tool they ship, with the operation each wraps.
get_provider_evidenceHow each part of their score was established. Free — the basis for a claim should not sit behind it.
get_provider_ratingPRO — composite, band, trend and facet scores.
apis_io_searchSTART HERE — APIs, providers and tags for one query, each with its total.
resolveTurn a domain, URL or GitHub org into the provider it belongs to.
find_cohortsEvery scored population of providers in the catalog.

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Every operation they expose

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