REST API Overview

The Fused platform API is an HTTP API. Everything the Python SDK and Workbench do goes through it, so any language that can make an HTTP request can create UDFs, run jobs, manage files, and automate Fused.

For the conceptual introduction — including the separate udf.ai endpoints for calling shared UDFs — see REST API in the Guide.

Base URL

https://www.fused.io/server/v1

Every path in this reference is relative to that base URL. Requests and responses are JSON unless noted otherwise.

Authentication

Pass credentials in the Authorization header. Two schemes are available:

Authorization: Bearer <access_token>
Authorization: Fused-Service-Token <service_account_token>

• Bearer — a personal access token that acts as you. Retrieve one from an authenticated SDK session with fused.api.access_token().
• Fused-Service-Token — a long-lived machine credential that acts as your team's environment. See Service Accounts.

Endpoint scopes

Each endpoint accepts one or both credential types. This reference labels every endpoint with its scope:

Scope	Accepts	Notes
User	Bearer only	Acts on resources owned by the signed-in user. A service account token is rejected.
Environment	Bearer or Fused-Service-Token	Acts on your team's execution environment. Suitable for automation.
User or environment	Bearer or Fused-Service-Token	Resolves to whichever identity you present.
By token	No header — the token in the path	Authorization is carried by the canvas or UDF token in the URL.
Public or authorized	Either, or none	Public resources are readable with no credentials; reaching private ones requires them.
Public	None	No credentials required.

note

"Environment" is your team's execution environment — the container for your team's UDFs, files, and quota. A service account token always resolves to an environment, never to an individual user, which is why user-scoped endpoints reject it.

Errors

The API uses standard HTTP status codes:

Status	Meaning
401 Unauthorized	Missing, malformed, or expired credentials
403 Forbidden	Authenticated, but not allowed to access this resource — including presenting a service account token to a user-scoped endpoint
404 Not Found	Resource does not exist, or you cannot see it
422 Unprocessable Entity	Request validation failed, or UDF execution failed

Validation errors return a detail array identifying each offending field:

{
  "detail": [
    {
      "loc": ["body", "name"],
      "msg": "Field required",
      "type": "missing"
    }
  ]
}

Other errors return a detail string.

Example request

curl -H "Authorization: Fused-Service-Token $FUSED_SERVICE_ACCOUNT_TOKEN" \
  "https://www.fused.io/server/v1/execution-env/self"

Reference

Section	Covers
UDFs	Creating, reading, updating, and deleting UDFs
Canvases	Canvases, sharing, and TOML import/export
Running UDFs	Executing UDFs by token, as tiles, or ad hoc
Batch jobs	Submitting long-running jobs, status, results, and logs
Files	Cloud file storage: list, upload, download, signed URLs
Environment	Execution environment, usage, and service accounts
Scheduled UDFs	Cron schedules for UDFs
Secrets	User secrets
Session tokens	Minting and revoking session tokens
Account	The signed-in user