What Makes Up an Agent
An agent is built from a few core building blocks:| Component | Purpose |
|---|---|
| Standard operating procedures | Step-by-step instructions the agent follows during conversations |
| Knowledge bases | Reference material the agent can look up on the fly — product info, policies, FAQs |
| Tools | API connections that let the agent take actions — look up orders, update records, transfer calls |
| Voice | How the agent sounds during calls |
| Parameters | Dynamic values passed in per call — customer name, order ID, account details |
Standard Operating Procedures
The most important part of an agent is its instructions — the standard operating procedures (SOPs) that tell the agent exactly how to handle a conversation. Good SOPs are structured, specific, and cover the scenarios the agent will encounter. Rather than giving the agent a vague goal, you tell it exactly what to do at each stage. For example, a support agent’s SOP might include:- Greet the caller and ask how you can help
- If the caller asks about an order, ask for the order number and look it up using the order status tool
- Read back the order status and ask if there is anything else
- If the caller asks about returns, reference the return policy from the knowledge base
- If the issue cannot be resolved, transfer the call to a live agent
Knowledge and Policies
Agents often need access to information that is too detailed or too frequently updated to put directly in the SOP — product catalogs, pricing tables, compliance policies, troubleshooting guides, or FAQ content. This is where knowledge bases come in. You attach one or more knowledge bases to an agent, and the agent searches them during the conversation when it needs to answer a question or reference a policy. This separation keeps your SOPs focused on the conversation flow while the knowledge base handles the reference material. Common use cases:- Company policies — return policies, warranty terms, billing rules, escalation criteria
- Product information — features, pricing, specifications, compatibility
- Troubleshooting guides — step-by-step diagnostic procedures
- FAQs — common questions and their approved answers
- Compliance scripts — required disclosures, legal language, opt-out instructions
Basic Agents vs. Flow-Based Agents
Basic Agents
A basic agent has a single set of SOPs, one voice, and an optional set of tools and knowledge bases. This is the fastest way to get started and works well for straightforward use cases like appointment confirmations, simple Q&A, or quick tests.Flow-Based Agents
Flow-based agents give you fine-grained control over the conversation by defining a state machine. Each node in the flow represents a distinct stage of the conversation, and you define which nodes the agent can transition to from each state. This is useful when:- The agent needs to collect specific information in a specific order
- Different parts of the conversation need different tools or knowledge
- You want to enforce a structured workflow (e.g., verify identity, then look up order, then offer resolution)
- Different stages require different SOPs
- SOPs — instructions specific to that stage of the conversation
- Tools — the set of tools available in that node
- Knowledge bases — reference material relevant to that node
- Transitions — which other nodes the agent can move to from here
- Greeting — verify the caller’s identity using an account lookup tool
- Issue triage — determine what the caller needs and route to the right node
- Order support — look up orders, check shipping, process returns (with order tools and return policy knowledge base)
- Billing support — review charges, process refunds (with billing tools and billing policy knowledge base)
- Escalation — transfer to a live agent when the issue cannot be resolved
Agent Voice
Every agent has a voice that controls how it sounds during calls. You can browse available voices through the dashboard or the Voices API and assign one to your agent.Agent Tools
Agents can interact with external services during a call using tools. You define the URL, headers, body format, and a description of when the tool should be used. The agent decides when to call each tool based on the conversation and its SOPs. Built-in capabilities include:- DTMF / IVR navigation — the agent can press keys on the keypad to navigate phone menus
- End call — the agent can hang up when the conversation is complete
- Transfer — the agent can transfer the call to another number or agent
Agent Parameters
Agents can accept parameters that are passed in when a call is created. These parameters can be referenced in the SOPs using{{parameter_name}} syntax, making each call personalized.
For example, an agent with the instruction “You are calling about order ” can receive those values dynamically from the API or from a campaign CSV upload.