What is Mozilla-Tabstack? AI crawler guide
Mozilla-Tabstack is a crawler or fetcher associated with Mozilla. See source-graded user-agent, robots.txt, verification, and observation guidance.
What is Mozilla-Tabstack?
Mozilla-Tabstack is a documented Mozilla crawler or fetcher. Agent for Tabstack, Mozilla's developer platform for programmatic, AI-driven interaction with web content.
Evidence status
| Field | Value |
|---|---|
| Evidence | Officially documented |
| Lifecycle | Active |
| Purpose | interaction |
| robots.txt posture | partial |
| Source checked | 2026-09-17 |
Documented user-agent
Mozilla-Tabstack/1.0 (+https://tabstack.ai)
robots.txt allow example
User-agent: Mozilla-Tabstack Allow: /
robots.txt block example
User-agent: Mozilla-Tabstack Disallow: /
What the rule can and cannot do
Robots.txt expresses an access policy to compliant automated crawlers. It does not authenticate the sender, remove content already collected, or guarantee that a model will use or not use content.
How to verify a request
- Match the complete documented user-agent where one exists. A match is only a clue.
- Look for operator-published IP ranges, reverse DNS, or signed-request guidance. None is attached to this record.
- Keep the observed request, operator documentation, and any inference as separate fields.
JavaScript behavior
The cited operator material does not verify JavaScript rendering. Serve useful HTML before client-side JavaScript where possible.
Related bots
- FirecrawlAgent: Another developer platform that fetches pages for AI applications.
- ApifyBot: Another developer platform that fetches pages for AI applications.
- ChatGPT Agent: Also tracked as a live fetcher.
- NovaAct: Also tracked as a live fetcher.
- GoogleAgent-Mariner: Also tracked as a live fetcher.
- Perplexity-User: Also tracked as a live fetcher.
- Claude-User: Also tracked as a live fetcher.
- Shap-User: Also tracked as a live fetcher.
- Robots.txt: Robots.txt is the control file used to block Mozilla-Tabstack.
- AI agent: Tabstack powers AI agents that read and act on web pages.
Frequently Asked Questions
What is Mozilla-Tabstack?
Mozilla-Tabstack is a officially documented crawler or fetcher record associated with Mozilla.
What user-agent does Mozilla-Tabstack use?
Mozilla-Tabstack/1.0 (+https://tabstack.ai). Check the evidence status before attributing a matching request.
Can Mozilla-Tabstack be blocked in robots.txt?
The record identifies Mozilla-Tabstack as the token to review. Robots.txt is a request policy, not proof of model use or non-use.
How can I verify a Mozilla-Tabstack request?
Treat the user-agent as a clue and look for operator-published IP, reverse-DNS, or signature guidance.
Data & Sources
- Mozilla documentation - Primary source for Mozilla-Tabstack crawler details.