> ## Documentation Index
> Fetch the complete documentation index at: https://docs.instructorphp.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Agent ctrl eventlog readback

## Overview

This example shows how to activate `EventLog` for an `AgentCtrl` execution,
run one Codex request through the builder path, then read the generated JSONL
file and print the captured entries on screen.

Key concepts:

* `EventLog::enable()`: activates the default JSONL sink for the current process
* `AgentCtrl::codex()`: uses the builder path, which currently honors `EventLog`
* JSONL readback: inspect execution, pipeline, and process events after the run

## Example

```php theme={null}
<?php
require 'examples/boot.php';
require_once 'examples/_support/eventlog_readback.php';

use Cognesy\AgentCtrl\AgentCtrl;
use Cognesy\Logging\EventLog;
use Cognesy\AgentCtrl\OpenAICodex\Domain\Enum\SandboxMode;

$logPath = ExampleEventLog::path('examples-d10-agentctrl-eventlog');

EventLog::enable($logPath);

try {
    $response = AgentCtrl::codex()
        ->withSandbox(SandboxMode::ReadOnly)
        ->execute('What is the capital of France? Answer briefly.');

    $entries = ExampleEventLog::read($logPath);
} finally {
    EventLog::disable();
}

echo "=== AgentCtrl Result ===\n";
if (!$response->isSuccess()) {
    echo "Error: Command failed with exit code {$response->exitCode}\n";
    exit(1);
}

echo "Answer: " . $response->text() . "\n";
if ($response->sessionId()) {
    echo "Thread ID: {$response->sessionId()}\n";
}
if ($response->usage()) {
    echo "Tokens: {$response->usage()->input} in / {$response->usage()->output} out\n";
}

echo "\n=== EventLog Entries ===\n";
echo "Log file: {$logPath}\n";
echo 'Entries captured: ' . count($entries) . "\n\n";

ExampleEventLog::print($entries, 10);

assert($response->isSuccess());
assert($response->text() !== '');
assert($entries !== []);
?>
```

## Expected Output

```
=== AgentCtrl Result ===
Answer: The capital of France is Paris.
Thread ID: thread-abc123
Tokens: 38 in / 24 out

=== EventLog Entries ===
Log file: /tmp/examples-d10-agentctrl-eventlog-xxxx.jsonl
Entries captured: 8

1. [2026-03-18T13:00:00+00:00] INFO agent-ctrl.bridge-builder AgentExecutionStarted
2. [2026-03-18T13:00:00+00:00] INFO agent-ctrl.bridge-builder RequestBuilt
3. [2026-03-18T13:00:00+00:00] INFO agent-ctrl.bridge-builder CommandSpecCreated
...
```

## Key Points

* **Builder path**: `AgentCtrl::codex()` flows through the bridge builder, which is currently wired to `EventLog`
* **Opt-in activation**: the JSONL sink is off until `EventLog::enable()` is called
* **Post-run inspection**: reading the JSONL file is a simple troubleshooting workflow for CLI-based agent runs
* **Current limitation**: direct bridge constructors still need separate wiring work to match this behavior