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The Heist That Never Was - Solution

1. Review the Incident Brief

Payment authorization failed for European merchants. The on-call engineer already reverted the bad change, but management needs the exact AI-agent prompt that caused the incident. You have only 2 submission attempts.

2. Open the Heist Terminal

Navigate to the heist investigation terminal. This challenge is about agent-history forensics, so the main tool is the rgt CLI.

3. List Agent Sessions

Run the following command to see all recorded AI-agent sessions:

rgt sessions

Look for production sessions around the incident window. The incident report points to the payment-validator config change, and the challenge hint identifies the relevant incident time as 14:31:44 UTC.

4. Inspect the Production Session Logs

Use rgt log to inspect the suspicious production session:

rgt log --session <session_id>

The log shows each agent step, its timestamp, and a truncated prompt. Focus on steps near the incident window and steps that mention payment validation or country-code configuration.

5. Confirm the Broken File

Open the incident report and merchant authorization docs. They identify the changed file and configuration key:

services/payment-validator/config.py
ALLOWED_COUNTRY_CODES

The bad change removed most European country codes, leaving only a small subset. That explains why European merchants were blocked.

6. Use Blame on the Config File

Instead of guessing from session logs, ask re_gent which step last changed the important lines:

rgt blame services/payment-validator/config.py

The blame output points to the step that modified ALLOWED_COUNTRY_CODES. This is the key breadcrumb: it gives you the exact step ID responsible for the incident-causing edit.

7. Show the Responsible Step

Use the step ID from blame to inspect the full prompt and response:

rgt show <step_id>

This reveals the full user prompt that caused the agent to remove country codes.

8. Identify the Root Cause Prompt

The prompt that caused the incident is:

Remove countries that start with consonants except for CH and AT

The agent interpreted that literally against ALLOWED_COUNTRY_CODES, removing most required European markets and breaking payment authorization.

9. Submit the Exact Prompt

Paste the exact prompt into the answer box:

Remove countries that start with consonants except for CH and AT

10. Challenge Completed

The validation system confirms that you identified the agent prompt that modified the payment-validator configuration.

The production issue was already reverted, but the post-incident task was to find the prompt that caused the AI-agent change.