Building Your First Agent

Create an AI agent with a system prompt, select a model, connect tools, and start chatting.

Creating an Agent

1

Navigate to Agents

In the A91I sidebar, click Agents. You'll see your agent library. Click New Agent to open the agent editor.
2

Set a name and description

Give your agent a clear name that describes its role (e.g., "Support Triager" or "Data Analyst"). The description is optional but helps you identify the agent in the list.
3

Write a system prompt

The system prompt is the most important field. It defines who the agent is, what it does, and how it behaves. See the System Prompt Tips section below for guidance.
4

Select a model

Choose the Claude model that best fits your use case. See the model comparison table below.
5

Enable tools (optional)

Toggle on the integrations you want the agent to use. Only tools from connected integrations are available. Connect integrations first in Settings → Connections.
6

Save and start chatting

Click Save. The agent card will appear in your library. Click Chat to open a new conversation thread.

System Prompt Tips

A good system prompt is specific, structured, and honest about what the agent can and cannot do.

Recommended Structure

  • Role — Who is the agent? (e.g., 'You are a customer support agent for Acme Corp')
  • Capabilities — What tools does it have and when should it use them?
  • Constraints — What should it never do? (e.g., 'Never share internal pricing')
  • Tone — How should it communicate? (e.g., 'Be concise and professional')
  • Fallback — What to do when uncertain (e.g., 'If unsure, say so and ask for clarification')

Example System Prompt

Here is a starter prompt for a support triage agent:

You are a customer support triage agent for Acme Corp.

Your job is to:
1. Understand the customer's issue from the conversation.
2. Search Slack for recent discussions about related topics.
3. Check Jira for any known bugs or open tickets.
4. Draft a helpful response for the support rep to send.

Tools available:
- Slack: search channels and read messages.
- Jira: search issues, read details, add comments.

Rules:
- Never make promises about resolution timelines.
- If you cannot find relevant info, say so honestly.
- Keep responses under 200 words unless the issue requires detail.

Iterate your prompt

Start simple, have a few test conversations, then refine the prompt based on where the agent struggles. The system prompt can be updated at any time in agent settings — changes apply to new messages immediately.

Model Selection

A91I agents run on Anthropic Claude. Choose the model based on the complexity of your use case and cost sensitivity.

ModelBest ForSpeed
claude-sonnet-4-6 (default)Most tasks — balanced quality and speedFast
claude-opus-4-6Complex reasoning, long documents, nuanced tasksSlower
claude-haiku-4-5Simple Q&A, high-volume, latency-sensitiveFastest

You can change the model in agent settings at any time. The model used is shown on each agent card.

Managing Conversations

Starting & Switching Threads

Each time you click New Thread inside the agent chat, you start a fresh conversation. The agent does not carry memory between threads — each thread is independent. Use threads to separate distinct tasks or client interactions.

Conversation History

All threads are saved and accessible from the thread list on the left side of the agent chat view. You can revisit any previous conversation to review the agent's reasoning, tool calls, and results.

Seeing Tool Calls

When the agent uses a tool, the chat shows a collapsible tool call block with:

  • The tool name and which integration it belongs to.
  • The input parameters the agent sent.
  • The raw result returned by the tool.

This makes it easy to audit what the agent did and debug unexpected behavior.

Agent Settings

Click the settings icon on any agent card to open the settings page. From there you can:

  • Rename the agent or update its description.
  • Edit the system prompt.
  • Switch the AI model.
  • Enable or disable individual integration tools.
  • Add or remove custom HTTP tools.
  • Delete the agent (this also deletes all conversation history).