What makes up an agent
| Component | What it does | Required |
|---|---|---|
| Language model | The LLM that generates responses | Yes |
| System prompt | Identity, personality, rules, and purpose | Yes (auto-generated or custom) |
| MCP tools | External services the agent can call | No |
| Agent-to-Agent | Other agents the agent can delegate to | No |
| Memory | Conversation history (short-term) or persistent context (long-term) | No |
| Knowledge base | Document collection for RAG-based answers | No |
| Integration channels | WhatsApp, Email — external communication interfaces | No |
| Pre-processor | Sentinels and empathy rules that run before the agent | No |
How agents run
When a user sends a message:Evaluation strategies
The evaluation strategy controls how the agent thinks. This is one of the most important settings for an agent.| Strategy | Description | Best for |
|---|---|---|
off | Single LLM call, no reasoning loop | Simple Q&A, content generation |
one-shoot | One call with tool schemas injected | Structured output, simple tool use |
tools | LLM calls tools in a single round | Deterministic, tool-first workflows |
react | ReAct loop: reason → act → observe → repeat | Multi-step tool use, complex tasks |
long-task | Extended planning for complex, multi-step tasks | Research agents, autonomous workflows |
When you add MCP servers or other agents to your agent, Studio automatically switches the evaluation strategy to
react. This ensures the agent can actually use its tools. You can override this manually in Dev Mode.The ReAct loop explained
react is the most powerful strategy. The agent follows this cycle:
- Reason — “I need to look up the user’s account to answer this”
- Act — calls the
get_accounttool from an MCP server - Observe — receives the tool result
- Reason again — “Now I have the account info, I can answer”
- Respond — generates the final answer
Next steps
Creating an Agent
Step-by-step walkthrough of the agent creation wizard.
Dev Mode
Take full control of the system prompt and evaluation strategy.