ChatGPT Agent vs Vellum
A side-by-side comparison of capabilities, autonomy, integrations, and pricing to help you choose.
Short answer: choose ChatGPT Agent if you want openai's agentic mode in chatgpt that browses, runs code, and acts (Supervised agent, subscription); choose Vellum if you want platform to build, evaluate, and deploy llm apps and ai agents (Supervised agent, contact).
| ChatGPT Agent | Vellum | |
|---|---|---|
| What it is | OpenAI's agentic mode in ChatGPT that browses, runs code, and acts | Platform to build, evaluate, and deploy LLM apps and AI agents |
| Type | product-with-agents | platform |
| Autonomy | Supervised agent | Supervised agent |
| Pricing | subscription · Included in ChatGPT Plus/Pro/Team/Enterprise plans | contact |
| Best for | consumers, smb, enterprise | developers, enterprise |
| Deployment | saas | saas, api |
| Modalities | text, browser, code | text, code, api |
| Models | gpt, proprietary | model-agnostic, gpt, claude, gemini |
| Protocols | function-calling, rest-api | mcp, function-calling, rest-api |
| Integrations | Gmail, GitHub, ChatGPT connectors | Composio, OpenAI, Anthropic, Google Gemini, AWS Bedrock, Cursor |
| Capabilities | 4 documented | 4 documented |
ChatGPT Agent
- +Unifies browsing (Operator) and analysis (Deep Research) into one agent
- +Acts on a virtual computer: browses, runs code, and builds deliverables
- +Available across ChatGPT paid plans with no separate product to adopt
- -Agentic browsing can be slow and error-prone on complex sites and login/CAPTCHA flows
- -Requires user oversight; not a hands-off autonomous worker
Vellum
- +Genuinely model-agnostic with a large, frequently updated catalog, avoiding lock-in
- +Covers the full LLM lifecycle (experiment, evaluate, deploy, monitor) in one place
- +Strong agent tooling with first-class MCP, Composio integrations, and auto-generated function-calling schemas
- -Brand and domain confusion: the apex vellum.ai domain appeared to host an unrelated product at this review
- -Platform pricing is not transparently published (sales-led, enterprise-leaning)
Which should you choose?
ChatGPT Agent is openai's agentic mode in chatgpt that browses, runs code, and acts, best for consumers, smb, enterprise. Vellum is platform to build, evaluate, and deploy llm apps and ai agents, best for developers, enterprise. The right choice depends on the autonomy level you want, your existing integrations, and your budget, all compared above.