ChatGPT Agent vs Tabstack (2026)

ChatGPT Agent

by OpenAI

Tabstack

by Mozilla

Pros

• ✓OpenAI names a direct replacement: ChatGPT Work for multi-step tasks and finished deliverables, with cloud browser for supported web workflows.
• ✓Cloud browser keeps working after the user leaves the conversation or closes the computer, and pauses when it needs input, a sign-in or a confirmation.

Limitations

• –OpenAI has discontinued ChatGPT Agent, so it can no longer be used or bought.
• –Cloud browser, its replacement for web tasks, runs only inside ChatGPT Work on paid plans in supported regions, and excludes Free and Go.

Pros

• ✓Each call returns finished output (a cited answer, schema-matched JSON, clean Markdown or a completed public-site task), so the calling model skips its own search-and-read loop.
• ✓Official Python and TypeScript SDKs, a CLI, an MCP server package and ready-built tools for eight agent frameworks.
• ✓Mozilla commits that neither Tabstack nor its contracted model providers use customer payloads to train models.

Limitations

• –No third-party security certifications today: Mozilla's documentation states that SOC 2 and ISO 27001 are not currently held.
• –Hosted Automate works on public websites only and does not sign in to accounts or store credentials.
• –Research and Automate bill a variable number of actions per call, so their credit cost depends on how many sources or steps each call takes.