Codex vs Respan Gateway: How They Actually Differ
Codex is a coding agent that runs across CLI, IDE, and cloud on GPT-5 models. Respan Gateway is an AI gateway with observability and evals built in. Pick Codex if you want an agent in your editor; pick Respan if you need one monitoring layer in front of multiple AI services.
Compiled 2026-10-18 from our catalogue entries for Codex and Respan Gateway.
The short answer
- Pick Codex if
- You want an AI agent in your terminal, IDE, and cloud on OpenAI's GPT models, with a GitHub pull request cloud code review and AGENTS.md plus MCP support out of the box.
- Pick Respan Gateway if
- You want a single AI gateway in front of AI services with observability and evals bundled in, accessed through a web platform, rather than a coding agent to drive in your editor.
- Cheapest way in
- Codex has a Free tier at $0 /month. Respan Gateway's pricing is not recorded in this entry, so no starting price is available.
- What we could not compare
- Respan Gateway has no published plans, no documented pricing, and only web access is listed, so CLI or IDE support, costs, and integration depth cannot be compared against Codex.
Codex and Respan Gateway both appear under AI Coding Agents but serve different jobs. Codex is an agent you hand tasks to, while Respan Gateway is positioned in this entry as gateway-and-monitoring infrastructure rather than an agent you code with directly.
Codex has a full fact sheet: pricing tiers, platform list, and a clear GitHub pull-request review feature. Respan Gateway's entry only confirms it is a web-accessed AI gateway with built-in observability and evals; pricing, plans, CLI, and IDE support are not recorded, so direct head-to-head detail on those points is limited.
Side by side
Every cell is a field on our catalogue entry for that tool, copied as recorded. Rows where the two differ come first; blank fields say so rather than being filled in.
| Codex | Respan Gateway | |
|---|---|---|
| Pricing model | Freemium | Not recorded |
| Starts at | Free — $0 /month | Not recorded |
| Runs on | web, mac, win, linux, cli, vscode-ext | Not recorded |
| Category | AI Coding Agents | AI Coding Agents |
| Public source code | No public repo listed | No public repo listed |
| Public docs | Not listed | Not listed |
- Public source code: From the repository link on each catalogue entry, not a licence audit.
Where Codex is the better fit
- Runs the same agent across CLI, IDE, desktop, and cloud, so work can move between surfaces.
- Cloud code review on a GitHub pull request that catches real bugs and proposes fixes inline.
- Reads the shared AGENTS.md standard and supports MCP tools.
- Included with ChatGPT plans from the free tier up through Pro, and runs on GPT-5 models.
Where Respan Gateway is the better fit
- Single AI gateway consolidating access to AI services in one place.
- Observability is a core feature rather than a separate add-on.
- Evaluation (evals) is a core feature rather than a separate add-on.
- Accessible through a web platform.
Which one should you pick?
It gives you an agent in the CLI and IDE on GPT-5, and the cloud PR review adds a second pass on incoming code.
Its stated edge is bundling the gateway with observability and evals as core features, accessed from a web platform.
A Free $0 /month plan is documented, with paid tiers from Go $8 /month up to Pro 20x $200 /month and an API key pay-per-token option.
Web, mac, win, linux, CLI, and a VS Code extension are all listed platforms, while Respan Gateway lists web only in this entry.
Frequently asked questions
- Is Respan Gateway a coding agent I drive directly?
- This entry positions it as gateway-and-monitoring infrastructure rather than an agent you code with directly. Codex is the one documented as an agent you work alongside.
- What platforms does Codex support?
- Web, mac, win, linux, CLI, and a VS Code extension are listed.
- Can Codex use non-OpenAI models like Claude or Gemini?
- The entry says Codex is locked to OpenAI's GPT models, with no Claude or Gemini out of the box.
- How much does Respan Gateway cost?
- Pricing is not recorded in this entry, and no verified plans are on file.
- Does Codex review GitHub pull requests?
- Yes, it runs a cloud code review on a pull request that comments inline and proposes fixes.
What we compared
This page states nothing that is not in the two catalogue entries below. The exact text used to write it is reproduced here so you can check our reading, and both tools link through to their own pages and to the vendor.
- /tools/codex — checked 2026-07-02 · official site
- /tools/respan-gateway — checked 2026-06-13 · official site
Show the source text
## Codex (/tools/codex) Tagline: OpenAI's coding agent — works in the terminal, IDE, and cloud, reviews GitHub pull requests, and runs on GPT-5 models. Category: AI Coding Agents Pricing model: freemium Starts at: Free — $0 /month Platforms: web, mac, win, linux, cli, vscode-ext Public repo: none listed Docs: none listed Verified plans (read 2026-08-21): Free $0 /month | Go $8 /month | Plus $20 /month | Pro 5x $100 /month | Pro 20x $200 /month | Business / Enterprise Not published | API Key Pay only for the tokens Codex uses, based on API pricing Strengths on file: Runs one agent across CLI, IDE, desktop, and cloud — work moves between surfaces.; Strong GitHub integration: a cloud code review on a pull request that catches real bugs and proposes fixes.; Reads the shared AGENTS.md standard and supports MCP tools.; Included with ChatGPT plans, from the free tier up through Pro. Limits on file: Locked to OpenAI's GPT models — no Claude or Gemini out of the box.; Fewer built-in customization primitives (hooks, sub-agents) than some rivals. Codex is OpenAI's agentic coding tool. It runs the same agent across a terminal CLI, an IDE extension, a desktop app, and a cloud environment, so work started in one surface can continue in another. It reads the shared AGENTS.md instructions file, speaks the Model Context Protocol (MCP), and can spin up a cloud code review on a GitHub pull request that comments inline and proposes fixes. Codex runs on OpenAI's GPT models — currently GPT-5.5 as the recommended frontier model — and is included with ChatGPT plans, from the free tier up through Pro. ## Respan Gateway (/tools/respan-gateway) Tagline: One AI gateway with built-in observability and evals Category: AI Coding Agents Pricing model: not recorded Starts at: Not recorded Platforms: not recorded Public repo: none listed Docs: none listed Verified plans: none on file Strengths on file: It is positioned as a single AI gateway consolidating access to AI services.; Built-in observability is a core feature of the product.; Built-in evaluation (evals) is a core feature of the product.; It is accessible through a web platform. Respan Gateway is an AI gateway that consolidates access to AI services, with observability and evaluation built in. Its stated edge is bundling: rather than wiring these up separately, it treats built-in observability and built-in evals as core features alongside the gateway itself. It is accessed through a web platform. It fits developers who want a single entry point to AI services with monitoring and evaluation included. Worth noting before committing: pricing is not publicly disclosed in this entry, and only web access is listed, with no documented CLI or IDE plugin support. Listed under AI coding agents, it positions as gateway-and-monitoring infrastructure rather than an agent you code with directly.
Change log
- 2026-10-18 — First published, compiled from the catalogue entries for Codex and Respan Gateway.