Kotoba

aid: kotoba
name: Kotoba
description: Kotoba Technologies is a Japan-founded frontier voice AI company building a foundational real-time speech model
  and simultaneous translation technology. Its developer platform exposes three JSON-over-WebSocket realtime capabilities
  — ASR (automatic speech recognition with live transcript deltas), STS (speech-to-speech translation that emits both a source
  transcript and synthesized target-language audio over one connection), and TTS (streaming text-to-speech) — alongside a
  REST transcription API for batch and offline workflows built on a submit-and-poll job model. Supported languages span English,
  Japanese, Korean, Chinese and Spanish. Each realtime channel is described by a published AsyncAPI 2.6.0 document and each
  REST surface by OpenAPI 3.1, with a first-party Python SDK, an llms.txt agent index, and a live remote MCP documentation
  server. The APIs are in private alpha, available to selected customers on request.
url: https://raw.githubusercontent.com/api-evangelist/kotoba/refs/heads/main/apis.yml
accessModel:
  pricing: unknown
  onboarding: self-serve
  trial: false
  try_now: false
  public: false
  label: Self-serve signup
  confidence: medium
  source:
  - authentication
  generated: '2026-07-22'
  method: derived
image: https://framerusercontent.com/images/7OW09ZoQn6c3oPwAHQgP3DCXI.png
x-type: company
x-source: vc-portfolio
x-backed-by:
- kindred-ventures
x-tier: enriched
x-tier-reason: openapi-asyncapi-mcp-sdk-published
specificationVersion: '0.20'
created: '2026-07-17'
modified: '2026-07-19'
tags:
- Company
- Artificial Intelligence
- Machine Learning
- Voice
- Speech Recognition
- Speech to Text
- Text to Speech
- Translation
- Real Time
- WebSockets
- Audio
- Transcription
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com
- FN: APIs.json
  email: info@apis.io
apis:
- aid: kotoba:kotoba-transcriptionapi-api
  name: Kotoba transcriptionApi API
  description: The transcriptionApi API from Kotoba — 2 operation(s) for transcriptionapi.
  humanURL: https://docs.kotoba.tech/s2t/batch
  baseURL: https://api.kotobatech.ai
  tags:
  - transcriptionApi
  properties:
  - type: OpenAPI
    url: openapi/kotoba-transcriptionapi-api-openapi.yml
  - type: Documentation
    url: https://docs.kotoba.tech/s2t/batch
  - type: AsyncAPI
    url: asyncapi/kotoba-asr-asyncapi.yml
  - type: Documentation
    url: https://docs.kotoba.tech/overview/capabilities/speech-to-text
  - type: AsyncAPI
    url: asyncapi/kotoba-sts-asyncapi.yml
  - type: Documentation
    url: https://docs.kotoba.tech/overview/capabilities/speech-to-speech
  - type: AsyncAPI
    url: asyncapi/kotoba-tts-asyncapi.yml
  - type: Documentation
    url: https://docs.kotoba.tech/overview/capabilities/text-to-speech
common:
- type: Website
  url: https://kotoba.tech/
- type: DeveloperPortal
  url: https://docs.kotoba.tech/
- type: Documentation
  url: https://docs.kotoba.tech/
- type: APIReference
  url: https://docs.kotoba.tech/s2t/streaming/asr/asr
- type: GettingStarted
  url: https://docs.kotoba.tech/overview/introduction
- type: Support
  url: https://site.kotoba.tech/contact
- type: SignUp
  url: https://app.kotoba.tech/
- type: Login
  url: https://app.kotoba.tech/
- type: Blog
  url: https://site.kotoba.tech/news
- type: TermsOfService
  url: https://dashboard.kotobatech.ai/terms_en.html
- type: PrivacyPolicy
  url: https://dashboard.kotobatech.ai/privacy_en.html
- type: GitHubOrganization
  url: https://github.com/kotoba-tech
- type: SourceCode
  url: https://github.com/kotoba-tech/kotoba-python
- type: X
  url: https://x.com/kotoba_tech
- type: LinkedIn
  url: https://www.linkedin.com/company/kotoba-tech/
- type: Authentication
  url: authentication/kotoba-authentication.yml
- type: OpenAPI
  url: openapi/kotoba-transcription-openapi-original.yml
- type: AsyncAPI
  url: asyncapi/kotoba-asr-asyncapi.yml
- type: Packages
  url: packages/kotoba-packages.yml
- type: SDKs
  url: packages/kotoba-packages.yml
- type: MCPServer
  url: mcp/kotoba-mcp.yml
- type: LLMsTxt
  url: llms/kotoba-llms.txt
- type: AgentSkill
  url: skills/_index.yml
- type: AgenticAccess
  url: agentic-access/kotoba-agentic-access.yml
- type: Conventions
  url: conventions/kotoba-conventions.yml
- type: ErrorCatalog
  url: errors/kotoba-problem-types.yml
- type: DataModel
  url: data-model/kotoba-data-model.yml
- type: Conformance
  url: conformance/kotoba-conformance.yml
- type: Lifecycle
  url: lifecycle/kotoba-lifecycle.yml
- type: WellKnown
  url: well-known/kotoba-well-known.yml
- type: DomainSecurity
  url: security/kotoba-domain-security.yml
- type: Overlay
  url: overlays/kotoba-transcription-overlay.yaml
x-enrichment:
  date: '2026-07-19'
  status: backfilled
  pass: local-v1
  note: backfilled from .gitignore signal + verified work evidence