Developer API

Proset exposes a REST API and a hosted MCP (Model Context Protocol) server. Both authenticate with a developer API key and operate only on the key owner's own data and plan.

Access and authentication

• REST base URL: https://proset.ai/api/v1
• MCP URL: https://proset.ai/mcp
• Authentication: send the API key as a bearer token in the Authorization header.

API keys use the format proset_ followed by 64 hexadecimal characters. A key is shown once at creation, stored as a one-way hash, and can be revoked at any time. The default expiry is 90 days; keys can also expire after 30 or 365 days, or never.

Keys are created and managed in the app under Settings → Developer, not through the API itself.

REST endpoints

Method	Path	Purpose
POST	/transcribe	Transcribe an audio file or base64-encoded audio into text.
POST	/convert	Convert a transcript into an artifact such as a summary, email, or spreadsheet.
GET	/me	Return the key owner's profile, plan tier, and usage.
GET	/usage	Return the key owner's plan limits and current usage.
GET	/recordings	List the key owner's recordings. Supports pagination and search.
GET	/recordings/{id}	Return one recording, including its transcript and artifacts.
GET	/thought-threads	List the key owner's Thought Threads.
GET	/thought-threads/{id}	Return one Thought Thread with its items and context sources.
GET	/folders	List the key owner's folders.
GET	/knowledge-bases	List the key owner's knowledge bases.

Transcription accepts an audio file in the multipart field audio or a audio_base64 JSON field, up to 500 MB. Conversion returns Markdown by default; pass outputFormat: "plain" for plain text.

Example request:

curl -X POST https://proset.ai/api/v1/transcribe \
  -H "Authorization: Bearer proset_..." \
  -F "[email protected]"

MCP tools

Tool	Purpose
transcribe	Transcribe base64-encoded audio.
convert	Convert a transcript into an artifact.
list_recordings	List recordings.
get_recording	Fetch one recording with its transcript and artifacts.
list_thought_threads	List Thought Threads.
get_thought_thread	Fetch one Thought Thread with its items and contexts.
list_folders	List folders.
get_usage	Return plan tier and usage limits.

Limits and metering

• Transcription and conversion count against the key owner's plan allowance, exactly like in-app use.
• Proset does not automatically bill usage overages. When AI Credits reach zero, requests stop until the monthly reset or more prepaid credits are available.
• AI requests are limited to 10 per minute per user.
• Every endpoint returns data for the key owner only. There is no access to another user's data.

Error codes

Code	Meaning
missing_api_key	No API key was provided.
invalid_api_key	The key is malformed, unknown, or revoked.
expired_api_key	The key has passed its expiry.
missing_audio	Transcription was requested without an audio file.
insufficient_tokens	No monthly or prepaid AI Credits remain. No automatic charge is made.
spending_cap_reached	The account's monthly spending cap is reached.
conversion_failed	Conversion could not be completed.

For connection steps, see Connect Proset to an AI assistant. For a guided first request, follow Build your first Proset API request, or read Why use the developer API and MCP server for the bigger picture.