> ## Documentation Index
> Fetch the complete documentation index at: https://docs.asisso.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Build an agent

> Assemble a Asisso voice agent programmatically with the SDK and save it as a draft

The SDK mirrors the node-and-edge model of the [Voice Agent Builder](/voice-agent/introduction). You create a `Workflow`, add nodes (`startCall`, `agentNode`, `endCall`, …) with `add()`, connect them with `edge()`, and persist the result via `save_workflow`.

## Prerequisites

* A Asisso [API key](/configurations/api-keys) exported as `ASISSO_API_KEY`
* An existing agent ID to save drafts against (create one in the Asisso UI or via [`POST /api/v1/workflow/create`](/api-reference/agents/create-from-template))

## Build and save

The example below builds a three-node loan-qualification agent and saves it as a **new draft version** on an existing agent. Your published agent keeps serving calls until you explicitly publish the draft.

<CodeGroup>
  ```python Python theme={null}
  from asisso_sdk import AsissoClient, Workflow

  with AsissoClient(api_key="YOUR_API_KEY") as client:
      wf = Workflow(client=client, name="loan_qualification")

      greeting = wf.add(
          type="startCall",
          name="greeting",
          prompt="You are Sarah from Acme Loans. Greet the caller warmly.",
      )
      qualify = wf.add(
          type="agentNode",
          name="qualify",
          prompt="Ask about loan amount, purpose, and monthly income.",
      )
      done = wf.add(
          type="endCall",
          name="done",
          prompt="Thank them and end the call politely.",
      )

      wf.edge(greeting, qualify, label="interested", condition="Caller wants to continue.")
      wf.edge(qualify, done, label="done", condition="All qualification questions answered.")

      client.save_workflow(workflow_id=123, workflow=wf)
  ```

  ```typescript TypeScript theme={null}
  import { AsissoClient, Workflow } from "@asisso/sdk";

  const client = new AsissoClient({ apiKey: "YOUR_API_KEY" });
  const wf = new Workflow({ client, name: "loan_qualification" });

  const greeting = await wf.add({
      type: "startCall",
      name: "greeting",
      prompt: "You are Sarah from Acme Loans. Greet the caller warmly.",
  });
  const qualify = await wf.add({
      type: "agentNode",
      name: "qualify",
      prompt: "Ask about loan amount, purpose, and monthly income.",
  });
  const done = await wf.add({
      type: "endCall",
      name: "done",
      prompt: "Thank them and end the call politely.",
  });

  wf.edge(greeting, qualify, { label: "interested", condition: "Caller wants to continue." });
  wf.edge(qualify, done, { label: "done", condition: "All qualification questions answered." });

  await client.saveWorkflow(123, wf);
  ```
</CodeGroup>

## Edit an existing agent

Load an agent into an editable `Workflow`, mutate it, then save:

<CodeGroup>
  ```python Python theme={null}
  wf = client.load_workflow(workflow_id=123)
  wf.name = "loan_qualification_v2"
  client.save_workflow(workflow_id=123, workflow=wf)
  ```

  ```typescript TypeScript theme={null}
  const wf = await client.loadWorkflow(123);
  wf.name = "loan_qualification_v2";
  await client.saveWorkflow(123, wf);
  ```
</CodeGroup>

## Discover node types

Each node's `type` string and required fields come from the backend's node-spec catalog. Fetch it at runtime to validate what you can build:

<CodeGroup>
  ```python Python theme={null}
  types = client.list_node_types()
  for spec in types.node_types:
      print(spec.name, [p.name for p in spec.properties])
  ```

  ```typescript TypeScript theme={null}
  const types = await client.listNodeTypes();
  for (const spec of types.node_types) {
      console.log(spec.name, spec.properties.map(p => p.name));
  }
  ```
</CodeGroup>

<Note>
  For a full description of each node type and its fields, see the [Nodes](/voice-agent/start-call) section of the Voice Agent Builder docs.
</Note>