agent

README

Agent Workflow

This example models an autonomous agent that investigates a problem (asynchronously), requests human approval, attempts a fix, and verifies the result. The agent can retry on failure — a RETRY event loops back to investigating — and an Always guard on the fixing state automatically bails out after two fix attempts, preventing infinite loops.

State Diagram

---
title: Agent Workflow
config:
    theme: default
    maxTextSize: 50000
    maxEdges: 500
    fontSize: 16
---
stateDiagram-v2
    state "approving" as approving
    state "done" as done
    state "fixing" as fixing
    state "investigating" as investigating
    state "verifying" as verifying
	done --> [*]
	[*] --> investigating
	approving --> fixing: YES
	approving --> done: NO
	fixing --> verifying: SUCCESS
	fixing --> investigating: RETRY
	fixing --> done: [maxAttempts]
	investigating --> approving: done.invoke
	investigating --> done: error
	verifying --> fixing: FAIL [canRetry]
	verifying --> done: FAIL
	verifying --> done: PASS

SCXML

<?xml version="1.0" encoding="UTF-8"?>
<scxml xmlns="http://www.w3.org/2005/07/scxml" version="1.0" name="agent" initial="investigating">
  <state id="approving">
    <transition event="YES" target="fixing"></transition>
    <transition event="NO" target="done"></transition>
  </state>
  <final id="done">
    <onentry></onentry>
  </final>
  <state id="fixing">
    <transition event="SUCCESS" target="verifying"></transition>
    <transition event="RETRY" target="investigating"></transition>
    <transition cond="maxAttempts" target="done"></transition>
  </state>
  <state id="investigating">
    <transition event="done.invoke.investigating" target="approving"></transition>
    <transition event="error.platform" target="done"></transition>
    <invoke id="investigating"></invoke>
  </state>
  <state id="verifying">
    <transition event="FAIL" cond="canRetry" target="fixing"></transition>
    <transition event="FAIL" target="done"></transition>
    <transition event="PASS" target="done"></transition>
  </state>
</scxml>

What Happens

The agent starts in investigating, which fires an async Invoke to run diagnostics. When the invocation completes, the done.invoke event moves the agent to approving. A simulated controller sends YES, advancing to fixing.

On the first fix attempt the controller sends RETRY, which loops back to investigating for another round of diagnostics. The agent goes through approving a second time, gets another YES, and lands in fixing again.

This time the controller sends SUCCESS, moving to verifying. The controller sends PASS, and the agent transitions to done — a final state whose entry action prints a completion message.

If the agent ever reached two fix attempts without success, the Always guard (maxAttempts) on fixing would fire automatically and send it straight to done, bypassing any further retries.

When To Use This

• CI/CD pipelines — build → test → deploy with automatic retry on transient failures and a hard cap on attempts.
• Customer support bots — triage → escalate → resolve, with human-approval gates between stages.
• Automated remediation — detect → diagnose → fix → verify, with retry budgets so the system doesn't loop forever.

Output

--- Starting Agent Actor ---
-> [investigating] Running diagnostics...
Current State: investigating
Current State: investigating
Current State: approving
Action: Sending YES
Current State: fixing
Action: Sending RETRY
-> [fixing] Retry attempt 1
-> [investigating] Running diagnostics...
Current State: investigating
Current State: investigating
Current State: approving
Action: Sending YES
Current State: fixing
Action: Sending SUCCESS
Current State: verifying
Action: Sending PASS
-> [done] Agent workflow complete.
Current State: done

Simulation finished.

Running

go run .