Launch preview. EvaEsi has not launched. These guides describe the API workflow at launch; API accounts and keys are not available from this website. Contact Forlais about API access.
POST /api/v1/responses. The older /api/v1/chat route is documented as a compatibility alias.Key concepts#
One model, five levels
EvaEsi is one model, EvaEsi 1.0. Every request goes to it. The level field sets how much work goes into the answer: look, focus, duet, high or hyper. See EvaEsi 1.0.
Rungs, not tokens
EvaEsi bills and reports usage in rungs. A rung is one character of answer at Focus. Each level uses a set number of rungs per character of answer, and input is priced at 30% of output.
- At Focus, a 1,200-character answer is 1,200 rungs
- At Look it is 600 rungs; at Duet 3,000; at High 4,200; at Hyper 5,400
- Input rungs and output rungs are reported separately on every response
Rooms and keys
The API works in rooms. A room is one EvaEsi, with its own memory, files and storage, shared by any number of API keys. Give each of your users a room and they keep their context across your products. Rooms are free, with 1 GB of storage each; more storage is 2p per GB a month. Rooms are created and managed in the API portal, and export or deletion of a room is free.
Prepaid credit
You pay from prepaid credit, with automatic recharge and spend limits you set. A new account starts with a spend tier of £100 a month, which rises with payment history and account age. The Developer plan includes £5 of credit every month. Prices are on the pricing page.
Session APIs vs bearer APIs
The documented launch workflow for the API portal at evaesi.dev uses signed-in session routes under /v1/*. Programmatic clients use bearer routes under /api/v1/*. Portal access opens with the platform at launch.
Public API#
| Endpoint | Description |
|---|---|
POST /api/v1/responses | Canonical single-request inference route |
GET /api/v1/sources/{request_id} | Live source bundle for a prior response |
GET /api/v1/usage | Current billing-period usage totals |
GET /api/v1/usage/history | Historical usage periods, newest first |
GET /api/v1/limits | Live request, rung and spend envelope |
GET /api/v1/models | The model and its levels |
Quick links#
| Guide | Description |
|---|---|
| Quickstart | A room, a key and your first request at launch |
| Authentication | API keys, scopes and rotation |
| EvaEsi 1.0 | The levels, their rungs and prices |
| Responses API | Canonical public inference route |
| Sources API | Live source lookup for prior requests |
| Usage API | Usage, history and limits response shapes |
| Limits and credit | Requests at a time, spend tiers and header behaviour |
| Pricing | Prices by level, rooms, storage and the Developer plan |
Base URL#
https://evaesi.dev/api/v1Authentication#
All public API requests require a bearer key:
Authorization: Bearer esi_dev_YOUR_API_KEY