Support desk

A real-world agent built the Go Micro way: a few services, an agent that manages them, an event that triggers it, and a human-in-the-loop gate on the one action that touches a customer. It's the "zero to hero" shape in one runnable file.

The scenario

A customer files a ticket. A ticket.created event triggers the support agent, which:

1. looks the customer up (customers service),
2. sets the ticket's priority (tickets service),
3. drafts a reply and emails it (notify service) — but only after passing the approval gate.

> event: events.ticket.created {"id":"ticket-1","customer":"[email protected]",...}

    [customers] looked up Alice (pro plan)
    [tickets]   ticket-1 → priority=high status=in_progress
    ▣ approval gate notify_NotifyService_Send([email protected]) — approved
    [notify]    📨 [email protected]: "Hi Alice — thanks for reaching out..."

✓ ticket triaged and the customer was replied to — triggered by an event

The pieces

• Services (customers, tickets, notify) — plain Go Micro services. The agent discovers their endpoints as tools automatically.
• Agent (support) — micro.NewAgent with those three services. It reasons over the ticket and calls the tools.
• Flow (intake) — triggers on events.ticket.created and hands the event to the agent: the event is the prompt. No human types anything.
• Guardrail (ApproveTool) — the agent can read and triage freely, but emailing a customer (notify.Send) passes through the gate first. Return false to hold it for a person or a policy; the example approves and logs.

Run

go run main.go            # mock model — deterministic, no API key

Against a live model, the agent reasons about the ticket itself instead of following the script:

export ANTHROPIC_API_KEY=sk-ant-...   # or OPENAI_API_KEY, GEMINI_API_KEY, ...
go run main.go -provider anthropic

What to change next

• Make the gate real: return false from ApproveTool for billing actions, or route the decision to a human.
• Expose the agent over A2A so another team's agent can file tickets — add agent.WithA2A(":4000").
• Add a kb (knowledge base) service and watch the agent search it before replying.