Publishers / substack.com
92
Mostly one web
13 of 14 AI agents get the full page at https://substack.com/. Checked 2026-09-25 09:33 UTC.
substack.com scores 92 out of 100 for machine visibility, number 6 of the 100 content publishers checked on 2026-09-25. 13 of 14 AI agents receive the full page: 7 of 8 training crawlers, 3 of 3 AI search indexes and 3 of 3 assistant fetchers. There is no llms.txt.
youfull pagedegradedblockedunknown
Human
- Status
- 200
- Title
- Substack
- H1
- none
- Words
- 326
- Scripts
- 48 tags · 109 KB
- Meta robots
- none
- Canonical
- https://substack.com/
- Server
- cloudflare
Machine
- robots.txt
- 4 groups · 2 sitemaps
- llms.txt
- missing
- llms-full.txt
- missing
- X-Robots-Tag
- none
- Blocked
- none
- Degraded
- Bytespider
- Challenged
- none
Gaps
- medium1 agents get a degraded pageBytespider: Different content than humans receive
- lowNo llms.txtOptional, but a short curated index at /llms.txt is the cheapest way to tell assistants what matters on this site.
Every agent
| Agent | Type | robots.txt | Fetch | Words | Result |
|---|---|---|---|---|---|
| Human (Chrome)You | Human | allowed | 200659 ms | 326 | visible HTTP 200, 326 words |
| GooglebotGoogle · Classic search index. Also feeds AI Overviews. | Search engine | allowed | 200631 ms | 326 | visible HTTP 200, 326 words |
| Google-ExtendedGoogle · Robots-only token controlling Gemini training use. Never fetches on its own. | AI training | allowed | n/a | visible Robots-only token; allowed by robots.txt | |
| GPTBotOpenAI · Training crawler for OpenAI models. | AI training | allowed | 200642 ms | 326 | visible HTTP 200, 326 words |
| OAI-SearchBotOpenAI · Indexes for ChatGPT search results and citations. | AI search index | allowed | 200652 ms | 326 | visible HTTP 200, 326 words |
| ChatGPT-UserOpenAI · Live fetch when a user asks ChatGPT about a page. | AI assistant (live fetch) | allowed | 200661 ms | 326 | visible HTTP 200, 326 words |
| ClaudeBotAnthropic · Training crawler for Claude models. | AI training | allowed | 200894 ms | 326 | visible HTTP 200, 326 words |
| Claude-SearchBotAnthropic · Indexes for Claude web search. | AI search index | allowed | 200653 ms | 326 | visible HTTP 200, 326 words |
| Claude-UserAnthropic · Live fetch when a user asks Claude about a page. | AI assistant (live fetch) | allowed | 200853 ms | 326 | visible HTTP 200, 326 words |
| PerplexityBotPerplexity | AI search index | allowed | 2001360 ms | 326 | visible HTTP 200, 326 words |
| Perplexity-UserPerplexity | AI assistant (live fetch) | allowed | 200649 ms | 326 | visible HTTP 200, 326 words |
| BingbotMicrosoft · Bing index. Also feeds Copilot and ChatGPT search. | Search engine | allowed | 200646 ms | 326 | visible HTTP 200, 326 words |
| Applebot-ExtendedApple · Robots-only token for Apple Intelligence training. | AI training | allowed | n/a | visible Robots-only token; allowed by robots.txt | |
| Meta-ExternalAgentMeta | AI training | allowed | 200887 ms | 326 | visible HTTP 200, 326 words |
| AmazonbotAmazon · Alexa and Amazon AI. | AI training | allowed | 200627 ms | 326 | visible HTTP 200, 326 words |
| BytespiderByteDance · Known for ignoring robots.txt. | AI training | allowed | 200625 ms | 304 | partial Different content than humans receive |
| CCBotCommon Crawl · Open dataset used to train most LLMs. | AI training | allowed | 200860 ms | 326 | visible HTTP 200, 326 words |
Snapshot
Measured 2026-09-25 09:33 UTC from a residential connection. Sites change their rules often, and sites that verify crawler IPs answer differently to different networks. Run a live comparison to see what substack.com does right now, from Cloudflare's network.