Models & Aliases

Requires Authentication

In Koldan, speech processing requests are always made using model aliases rather than direct model version identifiers. An alias is a stable reference that can be updated to point to different underlying model versions without changing your application code.

Model Aliases

A model alias can be one of three types:

• FAMILY: A high-level reference that always points to the latest recommended version of a model family (e.g., large-v3).
• PINNED: A reference that points to a specific, stable version of a model.
• CONCRETE: A direct reference to a specific model version (primarily used for internal tracking).

---

GET /api/v1/speech-services/models

Requires Authentication - Scopes: speech:model-aliases:read

Returns a list of all model aliases accessible to the current user. These are the identifiers you use in transcription and streaming requests.

ModelAliasListResponse

This endpoint returns an array of ModelAliasResponse objects.

ModelAliasResponse

Field	Type	Nullable	Description
id	string	No	Model alias identifier (e.g., large-v3).
type	string enum	No	Alias type. One of: FAMILY, PINNED, CONCRETE.
displayName	string	No	Human-readable name of the model.
description	string	Yes	Brief description of the model's purpose.
status	string enum	No	Availability status. One of: AVAILABLE, UNAVAILABLE, MAINTENANCE, DEPRECATED.
currentVersion	string	No	Current resolved model version name.
capabilities	ModelCapabilities	No	Technical capabilities and supported features.
deprecated	boolean	No	Whether this alias is deprecated.
deprecationDate	string (ISO 8601)	Yes	Date when the alias was marked as deprecated.
deprecationMessage	string	Yes	Information regarding deprecation or migration instructions.

ModelCapabilities

Field	Type	Nullable	Description
languages	string[]	No	List of supported BCP-47 language codes.
supportsLangAutodetect	boolean	No	Whether the model supports automatic language detection.
supportsStreaming	boolean	No	Whether the model supports real-time streaming transcription.

ModelAliasResponse

{
  "id": "large-v3",
  "type": "FAMILY",
  "displayName": "Large V3 (Multilingual)",
  "description": "Our most accurate multilingual model for general purpose transcription.",
  "status": "AVAILABLE",
  "currentVersion": "v3.0.2",
  "capabilities": {
    "languages": ["en", "he", "fr", "de", "es"],
    "supportsLangAutodetect": true,
    "supportsStreaming": true
  },
  "deprecated": false,
  "deprecationDate": null,
  "deprecationMessage": null
}

Status	Description
200 OK	List of available model aliases returned.
401 Unauthorized	Authentication required or token invalid.
403 Forbidden	Insufficient permissions (missing speech:model-aliases:read scope).

---

GET /api/v1/speech-services/models/{model}

Requires Authentication - Scopes: speech:model-aliases:read

Returns detailed information for a specific model alias.

Path Parameters

Field	Type	Required	Description
model	string	Yes	The name of the model alias.

ModelAliasResponse

Returns the same structure as described in the list endpoint.

Status	Description
200 OK	Model alias details returned.
401 Unauthorized	Authentication required or token invalid.
403 Forbidden	Insufficient permissions.
404 Not Found	Model alias not found.

---

GET /api/v1/speech-services/models/{model}/languages

Requires Authentication - Scopes: speech:model-aliases:read

Returns a list of supported languages for the specified model alias.

Path Parameters

Field	Type	Required	Description
model	string	Yes	The name of the model alias.

ModelLanguagesResponse

Field	Type	Nullable	Description
model	string	No	The model alias name.
supportsLangAutodetect	boolean	No	Whether the model supports automatic language detection.
languages	string[]	No	List of supported BCP-47 language codes (e.g., en, he).

ModelLanguagesResponse

{
  "model": "large-v3",
  "supportsLangAutodetect": true,
  "languages": ["en", "he", "fr", "de", "es", "it", "ja", "ko"]
}

Status	Description
200 OK	Supported languages returned successfully.
401 Unauthorized	Authentication required or token invalid.
403 Forbidden	Insufficient permissions.
404 Not Found	Model alias not found.