Fifth Door

Fifth Door is a San Francisco-based, Y Combinator-backed (Fall 2025) AI-native gaming startup founded by Amir Ghazvinian and Daniel Kan that lets anyone create, share, and play games simply by describing what they imagine, with no coding required. Its generative-AI platform turns natural-language prompts into playable, customizable games, aiming to collapse the time, cost, and technical complexity of traditional game development for players, creators, and studios. Backed by Felicis, the company runs a consumer web app and does not currently publish a public developer API or documentation.

Fifth Door is profiled on the APIs.io network. Tagged areas include Company, Gaming, Game Development, Artificial Intelligence, and Generative AI.

Fifth Door’s developer surface includes signup flow and 1 more developer resources.

🌐 Visit website 📡 Source on GitHub

5.0/100 minimal ▬ flat Agent 0/100 human only saas Full breakdown ↓
scored 2026-09-08 · rubric v0.20.0

0 APIs

Company Gaming Game Development Artificial Intelligence Generative AI No-Code Consumer Entertainment

Kin Score

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

Composite quality — 5.0/100 · minimal

Contract Quality 0.0 / 25

Developer Ergonomics 0.0 / 20

Access Clarity 0.0 / 20

Operational Transparency 0.0 / 13

Contract Governance 0.0 / 12

Discoverability 5.0 / 10

Agent readiness — 0/100 · human only

Machine-Readable Contract 0 / 18

Agentic Access Contract 0 / 10

Documented Reversibility 0 / 6

MCP Server 0 / 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 0 / 5

Registration Without a Human 0 / 6

Agentic Commerce Well-Known Document 0 / 5

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.

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Resources

Get Started 1

Portal, sign-up, and the first successful call

SignUp

SignUp

Company 1

The organization behind the API

Website

Website

Source (apis.yml)

aid: fifthdoor
name: Fifth Door
description: Fifth Door is a San Francisco-based, Y Combinator-backed (Fall 2025) AI-native gaming startup founded by Amir
  Ghazvinian and Daniel Kan that lets anyone create, share, and play games simply by describing what they imagine, with no
  coding required. Its generative-AI platform turns natural-language prompts into playable, customizable games, aiming to
  collapse the time, cost, and technical complexity of traditional game development for players, creators, and studios. Backed
  by Felicis, the company runs a consumer web app and does not currently publish a public developer API or documentation.
url: https://raw.githubusercontent.com/api-evangelist/fifthdoor/refs/heads/main/apis.yml
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: []
  generated: '2026-07-22'
  method: derived
image: https://cdn.magicpatterns.com/uploads/uE1x64XXGWkWodM5MrdtS7/Screenshot_2026-03-26_at_2.23.09_PM.png
x-type: company
x-source: vc-portfolio
x-backed-by:
- felicis
x-founders:
- Amir Ghazvinian
- Daniel Kan
x-tier: stub
x-tier-reason: portfolio-lead
specificationVersion: '0.23'
created: '2026-07-17'
modified: '2026-07-19'
tags:
- Company
- Gaming
- Game Development
- Artificial Intelligence
- Generative AI
- No-Code
- Consumer
- Entertainment
apis: []
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com
- FN: APIs.json
  email: info@apis.io
common:
- type: Website
  url: https://fifthdoor.com
- type: SignUp
  url: https://game.fifthdoor.com/launch
x-enrichment:
  date: '2026-07-19'
  status: backfilled
  pass: local-v1
  note: backfilled from .gitignore signal + verified work evidence

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