Price Flights in Cash vs Points with Codex

What you’ll build

A Codex agent with computer use that logs into your real credit card portals (Amex, Chase, Aeroplan), prices your trip in cash vs points across every option, and hands you one table with the best deal — so all you do is hit book. This exact run found a $799 open-jaw JFK → Casablanca / Marrakech → JFK for 63,914 Chase points at 1.25¢/pt value.

What you’ll need

• OpenAI Codex (the $20/mo ChatGPT plan works — expect to reset usage limits mid-run)
• Chrome logged into your card portals: Amex, Chase Travel, and any airline programs you hold
• Your points balances written down (e.g. 220k Amex MR, 81k Chase UR, 125k Aeroplan)
• A trip with fixed dates and airports

Step 1: Write the AGENTS.md brief

Create a project folder and put one AGENTS.md file in it. This file is the whole skill — if something isn’t in it, the agent will guess. Five sections:

# AGENTS.md

## The trip
Open-jaw: JFK → Casablanca (CMN) landing Nov 1, Marrakech (RAK) → JFK on Nov 12.
1 carry-on. Max 1–2 stops, no long layovers — prioritize the nonstop.

## The balances
220,000 Amex MR · 81,000 Chase UR · 125,000 Aeroplan.

## Hard rules
NEVER book anything. NEVER enter passenger info. NEVER transfer points.
Get to the checkout page, verify the deal is real, stop there.

## What to research
Google Flights average for these routes (the cash floor), then price the trip
inside every portal AND across transfer partners.

## The output
One comparison table — points, cash equivalent, cents-per-point — and one pick.

Ramble your version to Codex and let it draft the file, then read what it wrote back. It will surface questions you didn’t think to answer (cabin, baggage, layover tolerance) — answer them before it starts clicking.

Step 2: Price the cash floor first

Have Codex pull the Google Flights average for your exact routes and dates before it touches a portal. This number is the benchmark everything else has to beat. For this trip: $851 average, $799 best cash price.

Step 3: Turn Codex loose on your portals

Enable computer use with full access and let it click through your logged-in Chrome tabs — Amex Travel, Chase Travel, one at a time. Tell it explicitly:

Don't check out anything. Get to the checkout page, verify the deal is there,
and log every option to a running comparison file. I'll do the final booking myself.

Then walk away. It runs unattended for long stretches — check in when it pings you. On the $20 plan you’ll hit usage limits; use the limit resets and keep the same session going.

Step 4: Run the transfer-partner pass

Compact the session (or start a new one) and paste in the results so far. Now have it check part two: which transfer partners fly your route, whether a real seat exists, and the TOTAL cost — points plus cash surcharge. Rank by total, never by points alone: a 30k-point award with a $500 surcharge loses to 60k points + $50.

One warning: a points transfer is the only irreversible step in this whole process. Never transfer until the agent has confirmed a bookable seat — a chart rate is not a seat.

Step 5: Read the table and pick

The output for this trip:

Cash (Google Flights avg)   $851
Chase Travel                63,914 UR  (1.25¢/pt)   ← winner
Amex Travel                 79,900 MR  (1.0¢/pt)
Transfer partners           all lost — $500 AA surcharge, no Aeroplan availability

The math that decides it: cash price ÷ points = cents per point. Under your portal’s baseline rate (1.25¢ for Chase Sapphire), you lost. Over it, you won.

Step 6: Book it yourself

The agent stops at the checkout page — the actual booking is the one click it never gets. Log in, pull up the flight it found, redeem, done. 64,000 points, flight booked.