How ZCode, OpenCode and Codex differ, and where DeepSeek, GLM and OpenAI fit into my own setup.
Tyler Casey · Research 8 Sept 2026
Based on my own setup and the providers’ published documentation.
I use ZCode with DeepSeek Pro, GLM and OpenAI. I also use Codex to build and update websites, including Sideperk. That gives me two decisions to make: which coding tool I want to work in, and which model I want doing the work.
A coding harness is the software around an AI model: the interface, access to project files and the tools for editing code or running commands. ZCode, OpenCode and Codex each package that work differently. A model connection tells the harness which service to use for its responses.
| Tool | What it brings together | Model access | My setup |
|---|---|---|---|
| ZCode | A desktop workspace for files, terminal output and browser context, with Goal Mode for longer tasks. | GLM plus documented connections to other providers, including DeepSeek and OpenAI. | I use it with DeepSeek Pro, GLM and OpenAI. |
| OpenCode | An open-source coding agent available in the terminal, desktop and IDE. | Supported providers, local models and selected account connections. | An alternative included for comparison. |
| OpenAI Codex | Coding work across OpenAI’s app, terminal tool and editor integrations. | ChatGPT plan access or separately billed API use. | I use it to build and check websites, including Sideperk. |
Z.ai presents ZCode as a development environment built around GLM. Its appeal is the way a task can hold files, terminal results and browser context together. Goal Mode adds a place for longer pieces of work. The model settings also document DeepSeek and OpenAI connections, which is relevant to the mix I use.
OpenCode puts provider choice near the centre of its offering. It works in the terminal, desktop and IDE, supports local models, and advertises account connections for GitHub Copilot and ChatGPT Plus or Pro. It is a useful comparison for readers who want a coding tool they can use with several model services.
Codex is part of my day-to-day website work. I use it to turn a brief into code changes, investigate problems and inspect the result. OpenAI offers an app, terminal tool and editor integrations, with usage tied to the chosen account plan or API billing.
OpenCode’s software and selected models are free; other connected services have their own charges. ZCode documents a new-user GLM trial and paid coding plans, as well as API connections. Codex currently includes limited access with ChatGPT Free, with different allowances on other plans.
For my ZCode mix, the relevant distinction is between a GLM Coding Plan and separately billed API access. ZCode documents both routes. A GLM subscription does not include the DeepSeek or OpenAI usage you connect to it.
DeepSeek’s API bill depends on the model and the tokens sent and returned, including whether input is served from its cache. Those charges sit with the DeepSeek account.
The wider setup: OpenClaw, Notion and my Second Brain
Sources are linked above. Prices and plan conditions can change.
Desktop AI coding workspace
Building & APIs
ZCode is Z.ai’s desktop coding environment for planning, editing and reviewing software with AI agents. It brings files, terminal output and browser context into a task.
Goal Mode supports longer tasks, while model settings let you connect GLM and other compatible providers.
New-user GLM trial; paid plans and API connections
Tyler’s Pick · Source checked 8 Sept 2026AI models and coding subscriptions
AI & digital tools
GLM is Z.ai’s family of AI models. Its Coding Plan supplies model access to supported coding tools, while the general API serves applications and other integrations.
The Coding Plan is designed for supported coding tools; the general API is a separate route for using models in your own applications.
Coding subscriptions and usage-based API access
Tyler’s Pick · Source checked 8 Sept 2026AI models and developer API
AI & digital tools
DeepSeek provides AI models through its chat service and developer API. The API lets coding tools and applications send tasks to a selected DeepSeek model.
Its API offers separate input and output token pricing, with different rates for cached input and the selected model.
API usage billed by model and tokens
Tyler’s Pick · Source checked 8 Sept 2026Open-source coding agent
Building & APIs
OpenCode is an AI coding agent for the terminal, desktop and IDE. It helps write and change code while letting you choose from supported model providers or local models.
The same coding tool can use different providers, local models and supported account connections.
Free software and selected free models
AI coding and development
Building & APIs
Codex is OpenAI’s coding tool for writing, changing and reviewing software. It works across an app, the terminal and editor integrations, with access tied to your account or API use.
It connects coding work to OpenAI’s own models and account plans, with interfaces for desktop, terminal and editor use.
Limited access included with ChatGPT Free
Tyler’s Pick · Source checked 8 Sept 2026