Execution model
Agent
An Agent is an organization-owned definition containing instructions, an execution model, a maximum step count, tools, and Skills. It does not run when created or updated.
Agents created with an organization API key are API-only resources. They have no user owner and do not appear as editable Workspace Agents in the Rebyte UI.
Conversation
A Conversation is the durable context for one interaction. It owns the transcript and execution state across turns.
Agent version at creation
│ snapshot
▼
Conversation ── Response 1 ── Response 2 ── Response 3
Updating the Agent affects new Conversations. Existing Conversations keep their creation-time snapshot.
The Responses API uses IDs such as:
conv_550e8400-e29b-41d4-a716-446655440000
Pass that ID as conversation on every follow-up. Do not maintain a chain of
Response IDs.
The lower-level REST API calls the same resource a Session and exposes the
UUID without conv_. Session is a lower-level transport name, not a different
continuity model.
Response
A Response is one Agent turn. It has a resp_... ID, status, output text,
tool-call output, and streaming events.
The lower-level API stores that turn as a Message:
| Agent API concept | Lower-level REST name |
|---|---|
| Conversation | Session |
| Response | Message |
Use Responses for normal execution. Use Conversations and Messages when you need asynchronous submission, a standing event stream, interruption, or answers to Agent questions.
Organization ownership
An rbk_... key represents an organization, not a user. Agents,
Conversations, and Responses created by the key belong to that organization.
If your application has end users, keep the key on your server and enforce user-to-Conversation access before proxying a request.
Execution boundary
The Agent API owns Agent execution and durable interaction state. A configured tool may use a sandbox, browser, filesystem, or process, but those resources are not part of the Agent object model. Direct infrastructure control belongs to the separate Runtime API.