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Kernel Search

Kernel's search crawler that indexes web pages for AI-powered search and retrieval.
Kernel Technologies, Inc.KernelSearchBot
AI SearchAI Crawler

What is Kernel Search?

Kernel Search is the search-specific crawler operated by Kernel Technologies, Inc. It is separate from Kernel Agent, which runs browser automation in response to an end user's request. Kernel's bot documentation gives each identity a different purpose and verification authority.

The search crawler builds indexes and retrieval databases from web pages. Content it can fetch may become available to Kernel-powered search or retrieval, although a crawl does not guarantee that a page will be selected, quoted, or ranked for any query.

Kernel describes this identity as a search bot, not a model-training collector. There is no published claim that a Kernel Search visit adds the fetched page to foundation-model training data. Its direct consequence is eligibility for Kernel's search and retrieval systems.

Requests carry the KernelSearchBot token. Cloudflare's bot directory lists the full user agent as KernelSearchBot/1.0 (+https://www.kernel.sh/docs/bots), which is useful for log classification but can still be copied by an unrelated client.

Kernel also signs Search requests with Web Bot Auth. The Search identity publishes its keys at https://search.bot.kernel.sh/.well-known/http-message-signatures-directory. A verifier can use the Signature-Agent, Signature-Input, and Signature headers to check the request instead of accepting the user agent at face value.

Robots support is not settled in the supplied records. Kernel says the crawler follows rules for KernelSearchBot, including crawl-delay preferences, while Cloudflare's bot directory marks it as not following robots.txt. This page therefore treats compliance as unknown and recommends checking actual requests after a rule changes.

Relevant for AI search

Is Kernel Search relevant for AI search?

Yes. Kernel Search collects pages for an AI product, so what it can crawl influences how AI systems describe your brand.

Kernel Search crawls and indexes pages so the AI search or assistant behind it can retrieve them at answer time. A page it has never fetched cannot be quoted, summarized, or linked in that product's answers, so most sites keep it allowed to stay citable. Blocking it removes your pages from that AI surface and hands those citations to competitors.

How to handle Kernel Search

Keep Kernel Search reachable on pages you want available to Kernel retrieval. To request a complete block through robots.txt, use its documented token:

User-agent: KernelSearchBot
Disallow: /

Because the operator and Cloudflare's bot directory records disagree about compliance, inspect later requests before treating that directive as effective. Use path rules if only private documentation, account pages, or another bounded section should be excluded.

For a reliable allow or block decision at the edge, validate the Web Bot Auth signature against https://search.bot.kernel.sh/.well-known/http-message-signatures-directory. This prevents a spoofed KernelSearchBot string from inheriting the policy intended for Kernel.

Examples

  • A documentation team leaves installation guides open to Kernel Search but excludes a customer-only troubleshooting path.
  • A CDN rule verifies Kernel Search signatures before placing those requests in a crawler-specific rate limit.
  • A security engineer separates a signed `KernelSearchBot` request from a Kernel Agent visit because the two identities use different key directories.

Frequently asked questions about Kernel Search

Learn about AI visibility monitoring and how Promptwatch helps your brand succeed in AI search.

Kernel Technologies, Inc. operates Kernel Search directly. Its documented job is to crawl pages for search indexes and retrieval databases.

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