Subscription decision · 5 August 2026
Dropping Claude Max 20x to 5x and adding ChatGPT Plus for a second opinion is a sound plan. The maths is better than the tier names suggest, and the one real risk is specific to how you actually use Claude.
The advice you were given is real, not a hot take. Developers genuinely run both, and there is a reason it works: Claude Code has a bias to ship, and a second model with no memory of why a decision was made catches what the author quietly rationalised.
The part nobody mentions is that upgrades are prorated and instant. So going Max 5x for one month costs you nothing if it turns out to be too tight. That makes this a trial, not a commitment.
The tier names imply Max 20x gives you four times the headroom of Max 5x. On the weekly cap, which is the limit that actually bites, it does not.
| What you are comparing | Max 5x | Max 20x | Real difference |
|---|---|---|---|
| Price per month | $100 | $200 | 2.0× the cost |
| Weekly cap | baseline | approx 1.7× | 1.7× the ceiling |
| Per 5-hour window | approx 225 messages | higher | doubled for everyone, May 2026 |
| Claude Code hours per week | approx 140 to 280 | more | workload dependent |
You are currently paying double for roughly 1.7 times the weekly ceiling. That is the strongest argument for the downgrade, and it has nothing to do with ChatGPT.
This is the part general advice will not tell you, because it depends on your setup rather than the plan.
Max usage is one pool shared across Claude chat and Claude Code. It is not a separate coding allowance. And you are not a normal single-user case: you have 23 registered scheduled tasks running on that pool.
Four client analytics reports, four calendar refreshes, the twice-daily social intake and publish pair, the Gmail sweep, the Padharo ads safeguard, the monthly archive. The Ennio's report explicitly asks for Opus with extended thinking. None of that is you sitting at the keyboard, and all of it bills to the same weekly cap as your coding.
So the real question is not "will 5x handle my coding". It is "will 5x handle my coding plus roughly 23 unattended jobs a week". Watch that in month one, not just how the coding feels.
The workflow only pays off if the split is strict. Two agents doing the same job is waste; two agents doing different jobs is leverage.
Builder
Everything you already have lives here: your skills, MCP servers, hooks, subagents and scheduled tasks. It holds context across a long session and moves fast.
Reviewer
Reads the code as a stranger with no history of why any decision was made. Its only question is whether the thing actually works. That blindness is the feature.
Legwork
Already on your machine and already in your rules. It matters more on 5x than it did on 20x, because every job you hand it is one you do not spend from the shared pool.
These are in order and each one builds on the last. The whole point is that you never copy code between two windows. The filesystem is the integration.
One command. It logs in with the same ChatGPT account, so there is no separate API key to manage and nothing to put in a .env.
npm install -g @openai/codex
codex loginCodex reads AGENTS.md. Claude Code reads CLAUDE.md. Rather than maintain two files that drift apart, symlink one to the other so your British English rule, your no-dashes rule and your project conventions apply to both agents automatically.
ln -s CLAUDE.md AGENTS.mdDo this per project rather than globally, so a repo with its own conventions stays self contained.
This is the bit that makes it effortless. Register Codex as an MCP server inside Claude Code, and Claude can hand its own work over for review mid conversation.
claude mcp add codex -- codex mcp-serverVerify it came up before trusting it. Your own claude-doctor --deep will now include Codex in its MCP handshake check, so a broken registration shows up as a FAIL rather than silence.
Save this as ~/.claude/commands/secondopinion.md. It joins the five commands you already have, so review becomes /secondopinion rather than something you have to remember to do.
---
description: Hand the current change to Codex for an adversarial review
argument-hint: [optional focus, e.g. security]
---
Get an independent review of the work in progress from Codex.
1. Run `git diff` (and `git diff --staged`) to capture exactly
what changed. If the repo is clean, ask which files to review
instead of guessing.
2. Hand that diff to Codex via the codex MCP server, using the
adversarial review prompt: tell it to assume the author was
wrong, ignore stated intent, and only report defects it can
name a concrete failure case for.
3. If $ARGUMENTS names a focus (security, performance, edge
cases), pass that through as the priority lens.
4. Bring back only findings with a real failure scenario.
Discard style opinions and anything it cannot justify.
5. For each surviving finding, say plainly whether you agree.
Where you disagree, say why. Do not fix anything yet.
6. Then ask which fixes to apply.Claude commits, Codex reviews the diff. A diff is the cleanest possible handover because it carries the change and none of the conversation that produced it, which is exactly the ignorance you are paying the reviewer for.
git diff | codex exec "Review this diff. Assume the author
was wrong. Report only defects with a concrete failure case."A reviewer told to "check this code" agrees with you. A reviewer told to prove you wrong finds things. The framing is most of the value.
Your default. Paste into Codex, or let /secondopinion send it.
You are reviewing code written by another AI agent that had full
context on why each decision was made. You have none of that
context, and that is deliberate.
Assume the author was wrong. Your job is to find what actually
breaks, not to confirm the approach.
Report only defects where you can name a concrete failure:
specific inputs or state, and the wrong output or crash that
results. For each one give the file and line, what breaks, and
the smallest fix.
Ignore style, naming and formatting entirely. Ignore anything the
code comments claim, and check what the code does instead.
If you find nothing real, say so plainly. Do not pad the list.For when Claude has tried the same fix twice and it still fails.
Here is a bug another agent has failed to fix twice. Its two
attempts are below, and both were wrong.
Do not read those attempts as a starting point. They are evidence
of a wrong mental model, so treat the assumption behind them as
the prime suspect.
Tell me what the actual mechanism is, and what test would prove
it before any fix is written.Stops you applying a confident-sounding review that happens to be wrong.
Codex reviewed this and raised the findings below.
Go through them one at a time. For each, verify it yourself
against the actual code before agreeing. Where Codex is right,
say so and fix it. Where it is wrong or has missed context it
could not see, say that plainly and explain why, and do not
change the code.
Do not defer to it just because it is a second opinion.Decide by the end of the first billing cycle. The prorated upgrade is what makes this safe, so do not drift past it undecided.
Stay on Max 5x if
agy and scouting to the Haiku subagent by reflexGo back to 20x if
Two subscription changes, one install. Nothing else needs buying.
| Item | Action | Cost |
|---|---|---|
| Claude Max | Downgrade 20x to 5x at your next billing date | $100/mo |
| ChatGPT Plus | Subscribe at the Plus tier | $20/mo |
| Codex CLI | npm install -g @openai/codex | included |
| agy | Already installed. Lean on it harder | included |
| Codex IDE extension | Optional, only if you want review inside the editor | included |