Core concepts
| Concept | Description |
|---|---|
| Deployment | A dedicated AI agent for one customer: model, system prompt, skills, MCP tools, and connectors, running in an isolated container with a persistent filesystem |
| Thread | A conversation with a deployment’s agent. Every deployment starts with a default thread |
| Run | One unit of agent work, triggered by a message or an automation |
| Events | The SSE stream of tokens, tool calls, status updates, and steering requests from the deployment |
Prerequisites
- A Herm API key
Install the SDK
Create a deployment
Create an agent for a customer with your system prompt. This is the minimal version — see Deployments for skills, MCP servers, connector secrets, and feature flags.The response includes everything you need for the next steps:Save
deployment_id — you’ll reference it in every request that follows.Wait for the deployment to be ready
Provisioning usually completes in seconds. If
status is provisioning, poll Get a deployment until it flips to ready:Open the event stream
Open the SSE stream first so you catch every event from the run you’re about to start:If the connection drops, the SDK reconnects automatically and resumes from the last received event — see Stream Events.
Send your first message
Post a message to the deployment. Omitting
thread_id uses the default thread from step 1:What’s happening
When you send a message, Herm:- Routes it to the customer’s agent: every deployment is its own Hermes instance in its own container.
- Runs the agent loop: the model reasons, calls tools, observes results, and repeats until the task is done.
- Executes tools in the sandbox: file writes, shell commands, and your MCP tools run inside the deployment’s container.
- Streams events: you receive tokens, tool calls, and status changes in real time over SSE.
- Remembers: the workspace and observational memory persist, so the next run starts where this one left off.
Next steps
Deployments
Add skills, MCP servers, connector secrets, and feature flags.
Send Message
Threads, attachments, and image & video input.
Stream Events
Event types, steering requests, and reconnection.
Errors
Error codes and recovery steps.

