> ## Documentation Index
> Fetch the complete documentation index at: https://docs.usegradient.dev/llms.txt
> Use this file to discover all available pages before exploring further.
# Introduction
Gradient is the operating system for conversational agents. You build an agent as a graph of prompt nodes, ship it over phone and chat through one shared engine, and improve it with testing and evals that run in the same loop, not a separate tool bolted on afterward.
Voice and chat are the same agent. The graph, prompts, tools, and published versions are identical across every channel; only the transport differs.
## The loop
```mermaid theme={null}
flowchart LR
B["Build
nodes, prompts, tools"]
P["Publish
immutable versions"]
R["Run
chat, voice, API"]
E["Evaluate
datasets, redteam, rubrics"]
B --> P --> R --> E --> B
```
* **Build.** Author an agent as a topology of single-prompt nodes. Each node binds its own model, system prompt, and tools, and hands control to other nodes as the conversation moves.
* **Publish.** Freeze the draft into an immutable, numbered version. Live traffic only ever resolves to a version you shipped.
* **Run.** One engine runs that graph over dashboard chat, the public API, and phone calls.
* **Evaluate.** Redteam the real topology against a forked copy of your data, then grade both test and production conversations against one rubric.
## Start here
Build, publish, and call your first agent end to end.
The vocabulary: nodes, topology, versions, datasets, rubrics.
Author nodes, wire handoffs, and attach tools in the builder.
Define what correct means and grade every conversation against it.