> ## Documentation Index
> Fetch the complete documentation index at: https://docs.cartesia.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Changelog 2024

> Product, API, and platform changes for 2024

<Update label="December 2024">
  ### API

  * Pricing updates; character usage columns migrated to bigint; presign URLs for Pro Voice Clone; **`voices/<id>/conditioning`** endpoint; file to dataset in presign; userID-level endpoint restrictions; Stripe Customer ID on checkout.
  * EU deployment and Hindi HC fixes.

  ### Playground

  * New model on Playground highlighting **transcript following** improvements (demo, not GA).
  * Blog and play.cartesia.ai live.

  ### Models / Voices

  * Model aliasing updated for **`sonic`** and **`sonic-preview`**; twilight-morning in API and enterprise; conditioning entries for voice clone and multilingual.
  * Embedding search for LoRA voice selection.

  ### Other

  * Infrastructure and scaling updates.
  * State of Voice blog and map.
</Update>

<Update label="November 2024">
  ### API

  * **Cartesia-Version 2024-11-13** — Upgrade to new API version; **unified clone voice endpoint**; datasets support; files endpoint pagination; FineTuneRequest status; fine-tunes API in Playground; presign URLs for Pro Voice Clone; **Flush Done** event for manual WebSocket flushing; **`<pause>`** tag for continuations.
  * GCP Enterprise.

  ### Playground

  * Changes for new API; replay suite; GCP Enterprise.

  ### Models / Voices

  * **Flush Done** event for manual flushing in WebSocket; **`<pause>`** tag for continuations within a single transcript; spelling fixes; manual flush and flush ID.
  * Empty encoding field allowed for mp3.

  ### Docs

  * API version **2024-11-13**: Sonic 2, capability guides (clone, pronunciations, speed/emotion, continuations, localize), formatting for Sonic 2.
  * Integrations: LiveKit, Pipecat, Rasa, Thoughtly, Twilio, MCP. Enterprise: SSO, organizations. See [API Conventions](/use-the-api/api-conventions).
</Update>

<Update label="October 2024">
  ### API

  * Cartesia JS bytes endpoint; gen blocks removed from character counting; health checks and middleware; **user-level queueing** with queue length cap and timeout; 10× queue size rejection; Slang (continuations) and ConditioningData; voice changer JS SDK.
  * Remove max limit from Playground.

  ### Playground

  * GCP: API and ingress for GCP US Central. Queueing: user-level queueing in API gateway; queue length cap and `queuedRequest` timeout.
  * Voice Changer: Playground UI polish; ConditioningData as part of ResolvedVoice; Slang rollout; flush on start/end of spell tags.
  * LoRA release UI; onboarding data upsert fix; welcome page submit loading state; enterprise contact links.

  ### Other

  * Canonical linking and sitemap.
  * Blog and navigation (Blog, Careers) updates.
</Update>

<Update label="September 2024">
  ### API

  * User-level queueing; queue size and websocket queueing rejection; **`api_status`** field for voice API usability; LoRA pricing and UX cleanup; **flush all audio on DONE token** (including CB); user option to obfuscate transcripts in logs.
  * LoRA and load balancer improvements.

  ### Playground

  * **Function calling**; agent creation, tests, and dev setup; voice agent infrastructure enabled.
  * LoRA: HiFi cloning endpoint and Playground page; 8 new voices on Playground; Indian accent.
  * **Voice Changer** Playground UI; JS SDK for voice changer. Language added to TTS request from `voices/[id]`; flush all audio on DONE token; user option to obfuscate transcripts in logs.

  ### Docs

  * Blog and sitemap updates.
</Update>

<Update label="August 2024">
  ### API

  * Reject invalid transcripts (docs and API gateway); `no_more_inputs` in WebSockets can use `voice_embedding` instead of `voice_id`.
  * Improved bad model id handling.

  ### Playground

  * **Localization** page in Playground and JS client; dialects and future-compatibility. Switch Playground to voice ID; allow both `id` and embedding for `TTSRequest`; archive voices (kept accessible via API).
  * Replay button; feedback form; fix multilingual recommended voices when switching back to English; better error messaging.

  ### Models / Voices

  * **LoRA** support (multiple voices per LoRA, new cache key, easy-brook-lora, vc-flowing-dream).

  ### Other

  * On-device homepage launch; proper links for "Request a demo" button.
  * **LoRA**: multiple voices per LoRA.
</Update>

<Update label="July 2024">
  ### API

  * **Voice Conversion endpoint** — New API endpoint. **Timestamps** on WebSocket endpoint; **per-generation voice controls** (speed, emotion) in API; polar-tree deployed (`sonic-multilingual`); continuous batching support; VocalWave (English) and long-generation support; `sonic-english` → vocal-wave, `sonic-multilingual` → ancient-voice aliasing.
  * **`buffer`** and **`mp3`** params on `/bytes`; MP3 streaming and WAV encoding fixes; request cancellation; empty transcript allowed when `continue=false`; Stripe webhook cache clear; subscription cancellation/reactivation; Redis cache for overage; keys endpoints.
  * Clerk-based auth in API.

  ### Playground

  * Optional **`enhance`** flag for voice cloning in JS client, Python client, and Playground; voice update endpoint and docs; gate voice cloning for free users.
  * Prevent playing audio while playback in progress; download button disabled until generation finished; API key deletion clearer with copy button; character usage indicator; subscription and checkout fixes; gating clone form for free users.

  ### Docs

  * Voice cloning docs; timestamps and continuations; user guides for voice control and Twilio; emotion control and timestamps; "phonemes" terminology.
  * Voice cloning from file.

  ### Other

  * Python client: continuations support, custom `base_url`, fallback for websockets; JS client v1.0.1: `onError` prop on useTTS.
  * Voice controls (speed, emotion) in Python client and docs.
</Update>

<Update label="June 2024">
  ### API

  * **Continuations** — Support for streaming input via SSE and Bytes; **`NoMoreInputs`** signal. **Cartesia Version** enforced via header; Playground and checkout/subscription endpoints send it.
  * 48 kHz added to valid sample rates; `.wav` byte streaming; HTTP streaming endpoint for raw bytes; API standardization (backwards-compatible); new voices endpoints; mulaw and alaw backwards compatibility; Python client v1.0.0 (overhaul, `output_format`); JS client: `pcm_s16le`, `pcm_alaw`, `pcm_mulaw` and improved typing; caching for voices; **`context_id`** in WebSocket response and docs.
  * Stripe webhooks for renewals and expiration; OpenAPI spec update.

  ### Playground

  * Multilingual: `language` parameter on voices API and in API; Playground language selection; multilingual copy on homepage; default `sonic-english` → feasible-haze.
  * Mobile layout improvements; multilingual UI papercuts; voice cloning and empty transcript styling fixes; filtering moved from `voices/[id]` to Speak page.

  ### Models / Voices

  * **`sonic-multilingual`** and **`sonic-english`** aliasing; `language` column on voices.
  * Recommended voices.

  ### Docs

  * Version **2024-06-10**: get-started, API conventions, integrations (LiveKit, Pipecat, Rasa, Thoughtly, Twilio, MCP), clone voices, embeddings/voice mixing. See [API Conventions](/use-the-api/api-conventions).

  ### Other

  * ToS changes; revised pricing tiers; legal notices on sign-in and sign-up; overage toggle in Playground.
  * Character usage limit blocks WebSocket when exceeded.
</Update>

<Update label="May 2024">
  ### API

  * **Cartesia Version** header; HTTP streaming for raw bytes; new voices endpoints; mulaw/alaw backwards compatibility; API standardization (backwards-compatible); Python client v1.0.0; JS client structure overhaul.
  * Clone voice upload fix.

  ### Playground

  * Redesign and Sonic launch copy; subscriptions page; favoriting voices; **emotion and speed sliders**; User vs Default voices; **tags** (Age, Accent) in DB and Playground; **`sample_text`** field (API Gateway and Playground); buffer streamed audio before playback; character usage indicator; API key auto-created on user creation; custom sign-in/sign-up and 404 on sign-out fix; disable generation button while audio playing; human-readable model names and skilled-cherry.
  * Character limit increase.

  ### Models / Voices

  * Human-readable model names; skilled-cherry; polar-tree (`sonic-multilingual`); continuations and output format; Python client numpy array support.
  * Voice cloning disclaimer.

  ### Docs

  * Mintlify docs added.

  ### Other

  * Stripe webhooks for subscriptions; subscription cancellation and reactivation; character usage checks on generation routes; free subscription by default; Scale plan limit (8M chars/month); checkout and receipts.
  * Custom sign-in/sign-up pages.
</Update>

<Update label="April 2024">
  ### API

  * **`model_id`** added as parameter to generate; minimum transcript length enforced; `voice` moved to `AudioGenerationRequest`; experimental router removed; speed controls and voice edit page; video generation endpoint.
  * WhisperX removed from dependencies.
</Update>

<Update label="March 2024">
  ### API

  * WebSocket interrupt support; get voice embedding route; Redis cache for API keys; streaming switched from Octet to JSON; new model `genial-planet-1346`; `voice` param required on requests; formatting support.
  * WhisperX for transcription (later removed).

  ### Playground

  * Voice cloning in the UI; connection info in JS client; audio downloadable; transcript length validation (max 400 chars, empty rejected); improved UX and crash handling when API key missing; welcome message and icons.
  * API key creation on sign-up via Clerk webhooks.

  ### Other

  * Voice cloning and connection info in JS client.
</Update>