API Reference

Use the API when you need code-level control.

The Agent execution APIs use four related resources:

1. define versioned Agents
2. create stateful Sessions and exchange events
3. expose Agents through callable Endpoints
4. create a Schedule through the Deployments API and inspect DeploymentRuns and linked Sessions

Common APIs

Area	Use it for	Start here
Models	Call LLM, image, audio, video, and embedding models	Chat Completions
Task costs	Poll recent async model task settlement, final cost, estimates, and usage	Get Task Cost
Agents	Create and version reusable Agent definitions	Agents API
Sessions	Run an Agent statefully and exchange events	Sessions API
Endpoints	Publish and invoke an Agent over REST	Endpoints API
Deployments	Schedule or manually trigger repeatable Agent work	Deployments API
DeploymentRuns	Inspect each Deployment trigger and its nullable Session result	DeploymentRuns
Skills	Create and manage reusable Agent instruction bundles	Skills API
Webhooks	Receive notifications when async work completes or fails	Webhooks

Task cost lookup is intended for recent task-level settlement polling. Older task execution records may be archived and become unavailable from this endpoint; use billing records or billing exports for long-term reconciliation.

Authentication

Most API requests use a SandBase API key:

Authorization: Bearer sk-sb-YOUR_KEY

Some Anthropic-compatible clients use:

x-api-key: sk-sb-YOUR_KEY

Learn more: Authentication.

Resource relationships

• An Agent is configuration and does not execute by itself.
• A Session is a stateful Agent execution. Input and output are persisted as Session events.
• A Service is backed by an Endpoint resource. Calling POST /v1/endpoints/{id}/run creates or continues a Session.
• A Schedule is managed through a Deployment resource and stores repeatable input with an optional cron expression. Every trigger creates a drun_* DeploymentRun and, on success, a new linked Session.

Next steps

• Getting Started
• Store
• Setup
• Get Task Cost
• Build Agent