GPT-5.3 Codex
TL;DR
PremiumHeavy-duty code generation and long coding sessions.
Available on
Not on the Go plan ($1/mo, open-source models only).
Switch with
Pick GPT-5.3 Codex from the selector.
Intelligence Index
GPT-5.3 Codex vs the OpenAI lineup
GPT-5.4
GPT-5.3 Codex
GPT-5.4 Mini
Speed
~72
tokens / sec
Input
$2
per M tokens
Output
$8
per M tokens
GPT-5.3 Codex in Command Code
GPT-5.3 Codex is OpenAI's coding-specialized model — tuned for heavy-duty code generation and long agent sessions where the model writes for many turns. Output is cheaper than GPT-5.4 ($8 vs $15 / M), which matters when sessions run long.
Codex vs the Command Code lineup
Quality, speed, and pricing for Codex alongside the most relevant alternatives.
| Model | Intelligence | Speed | Input $/M | Output $/M |
|---|---|---|---|---|
| GPT-5.3 Codex | 54 | ~72 tok/s | $2.00 | $8.00 |
| GPT-5.4 | 57 | ~84 tok/s | $2.50 | $15.00 |
| GPT-5.4 Mini | 49 | ~164 tok/s | $0.75 | $4.50 |
| Claude Sonnet 4.6 | 52 | ~62 tok/s | $3.00 | $15.00 |
| Claude Opus 4.7 | 57 | ~49 tok/s | $5.00 | $25.00 |
| Kimi K2.6 | 54 | ~40 tok/s | $0.95 | $4.00 |
What Codex is best for
Heavy-duty code generation, long coding sessions, large output volumes, and tasks that benefit from a code-specialized model.
When to switch away from Codex
Switch to GPT-5.4
For mixed tasks where general reasoning matters more than coding specialization. Higher Intelligence (57 vs 54), faster output.
Switch to GPT-5.4 Mini
For everyday short tasks. Mini is much faster (~164 tok/s) and significantly cheaper.
Switch to Claude Sonnet 4.6
For the Claude family on everyday work — the recommended Command Code default.
Switch to Kimi K2.6
For open-source economics with comparable Intelligence (54). Available on every plan including Go.
In Command Code: caching and taste-1
Two things change the experience of using this model inside Command Code versus calling it directly through the upstream API.
First, prompt caching is on by default. In an agent loop the same context is read across many steps; cache reads are billed at $0.50 per million tokens versus $2.00 for fresh input.
Second, taste-1 sits between the model and the agent loop, rewriting and reranking candidate edits to match your codebase conventions. Each plan ships with a taste-1 usage allowance that scales by tier (Go $100 → Ultra $10,000).
Plan availability
Premium model. Available on Pro ($15/mo), Max ($100/mo), Ultra ($200/mo), Teams ($40/mo per seat), and Enterprise. Not on the Go plan.
All Command Code models, ranked by quality and speed
Quality is the Intelligence Index — an aggregate score across reasoning, math, coding, and knowledge evaluations. Speed is reported output tokens per second. Models without a published score are noted.
| Model | Tier | Intelligence Index | Output speed |
|---|---|---|---|
| GPT-5.5 | Premium | 60 | ~65 tok/s |
| Claude Opus 4.7 | Premium | 57 | ~49 tok/s |
| GPT-5.4 | Premium | 57 | ~84 tok/s |
| GPT-5.3 Codex | Premium | 54 | ~72 tok/s |
| Kimi K2.6 | Open-source | 54 | ~40 tok/s |
| Claude Sonnet 4.6 | Premium | 52 | ~62 tok/s |
| DeepSeek V4 Pro | Open-source | 52 | ~35 tok/s |
| GLM-5 | Open-source | 50 | ~61 tok/s |
| GPT-5.4 Mini | Premium | 49 | ~164 tok/s |
| DeepSeek V4 Flash | Open-source | 47 | ~82 tok/s |
| Claude Haiku 4.5 | Premium | 37 | ~97 tok/s |
| Kimi K2.5 | Open-source | 37 | ~35 tok/s |
| Claude Opus 4.6 | Premium | Not yet scored | — |
| MiniMax M2.5 | Open-source | Not yet scored | — |
Switching models with /model
In an interactive Command Code session, run /model to open the model selector. Pick the model you want and it applies to this session and to future sessions until you change it again. Premium models require Pro or higher; open-source models are available on every plan, including Go.
cmd # start an interactive session
/model # open the selector and pick a modelPlans and pricing
Command Code is a subscription with model usage at API rates. Each plan ships with monthly LLM credits and a separate taste-1 usage allowance that scales by tier. Credits roll over and never expire. Auto top-up keeps you running if you go over.
| Plan | Price/mo | LLM credits | taste-1 usage | Models |
|---|---|---|---|---|
| Go | $1 | $10 | $100 | Open-source only |
| Pro | $15 | $30 | $500 | Open-source + premium |
| Max | $100 | $150 | $5,000 | Open-source + premium |
| Ultra | $200 | $300 | $10,000 | Open-source + premium |
| Teams | $40 / seat | Pooled | $1,000 | Open-source + premium |
| Enterprise | Custom | Custom | Custom | Custom pool, SSO, audit logs |
Frequently asked questions
Codex or GPT-5.4?
GPT-5.4 is more flexible (Intelligence 57 vs 54). Codex is cheaper on output ($8 vs $15 / M) and tuned for long coding sessions.
Codex or Kimi K2.6?
Both score 54. Codex is twice as fast (~72 vs ~40 tok/s) but more expensive on input ($2 vs $0.95). K2.6 is open-source and available on every plan including Go.
Which Command Code model should I use?
Claude Sonnet 4.6 is the recommended default. Switch to GPT-5.5 (Intelligence Index 60) for the absolute hardest reasoning, or Claude Opus 4.7 / GPT-5.4 (both 57) for top-tier work at lower cost. For fast lookups, Claude Haiku 4.5 or GPT-5.4 Mini. For open-source, Kimi K2.6 leads the open-weights tier (Intelligence Index 54).
Can I mix GPT-5.3 Codex with other models in a workflow?
Yes. Switch per session using /model. Common pattern: keep Sonnet 4.6 as the default and switch up to Opus 4.7 or down to Haiku 4.5 as the task calls for it.
Are open-source model prices fixed?
Open-source models are routed across multiple upstream providers for high availability. The price listed for each is the mean per-provider rate. Actual cost on a given request may vary slightly. The Usage page reflects the price charged.
Is Command Code free to try?
The Go plan starts at $1/mo with $10 in LLM credits and $100 of taste-1 usage. It covers open-source models only. Pro at $15/mo unlocks premium models with $30 in LLM credits and $500 of taste-1 usage.
Does Command Code train on my code?
No. Command Code does not train on your code or store your code snippets. taste-1 data is stored locally in your project directory.
Where can I track my usage?
The Usage page in Studio shows per-request cost, token counts, and which model ran. Settings > Billing lets you change plans, buy credits, or enable auto top-up.
Does Command Code replace my editor?
No. Command Code is editor-agnostic — it runs as a CLI and works alongside any editor (Cursor, VS Code, Zed, JetBrains, Neovim, etc.).
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