Claude Search Optimisation

Claude’s web search launched in the United States in March 2025 and went global across all plans in May 2025.¹ It retrieves current web content to answer queries and cites sources inline. The retrieval backend appears to be Brave Search rather than Google or Bing, which is the central fact for content strategy: Google rankings do not translate directly into Claude citations.

Does Claude really run on Brave Search?

The evidence is strong but it is not a vendor statement, and the distinction is worth keeping.

In March 2025 Anthropic added Brave Search to its published subprocessor list, the register of partners that process Claude data.² Independently, the programmer Simon Willison found that Claude’s citations for a test query matched Brave’s results for that query exactly, and identified a BraveSearchParams parameter inside Claude’s web search function.² Anthropic itself documents three crawlers and describes Claude-SearchBot’s role, but has never publicly named its search provider.³

So: a legal disclosure plus independent technical replication, and no official confirmation. That is more than enough to plan content around, and it is not the same as Anthropic saying so. Treat the arrangement as evidenced rather than announced, and as something that could change without a press release.

You may also encounter a widely repeated statistic putting the overlap between Claude’s citations and Brave’s top results at 86.7%, with a p-value attached. It comes from a vendor analysis of fifteen results. The direction it points is right; the precision is not real, and we do not rely on it here.

How does Claude retrieve and cite?

When a query requires current information, Claude reformulates the user’s question into a more search-optimised form and issues it to the search backend rather than passing the original prompt through. It then retrieves candidate results and, where necessary, fetches specific pages to read in detail. Two consequences follow: a page must be present in the index Claude queries, and it must hold up when read. Ranking gets you considered; the content earns the citation.

Citations appear inline within Claude’s prose as numbered references, embedded where the content is relevant to the point being made. This differs from Perplexity’s sidebar source list and ChatGPT’s citation list appended to the end of the response. Inline placement means citations appear where users are actively reading, giving cited sources contextual visibility rather than a footnote position.

What are Anthropic’s three crawlers?

Anthropic documents three crawlers, each with a distinct purpose.³ Conflating them is a common mistake with direct consequences for robots.txt decisions.

ClaudeBot collects web content that may be used to train Anthropic’s models. Blocking it excludes your site from future training data. It has no effect on whether Claude cites you in a search response.

Claude-SearchBot “navigates the web to improve search result quality for users”.³ This is the crawler that matters for citation visibility. Blocking it reduces your chance of appearing in Claude’s search responses.

Claude-User fetches a specific page during a live session, for instance when someone pastes a URL and asks Claude to summarise it. It sits outside the search indexing pipeline.

For citation visibility the relevant user agent is Claude-SearchBot. Blocking ClaudeBot, by far the most discussed of the three, has no effect on Claude’s ability to retrieve and cite your content.

What does Claude favour?

Brave Search ranking. Before any of Claude’s citation logic applies, your page must be in Brave’s index and rank for the query Claude generates internally. Brave serves its web results from its own index: it removed the last of its Bing API calls in April 2023, which had accounted for roughly 7% of results.⁴ Ranking factors broadly resemble Google’s, but Brave weights editorial authenticity more explicitly: real authors with verifiable credentials, transparent sourcing, and content written for readers rather than for rankings.

Named, credible authorship. Author authority signals carry more weight in Claude’s citation behaviour than in most other AI surfaces. A named author linked to a verifiable profile (personal site, LinkedIn, or institutional affiliation) is treated differently from anonymous or byline-free content. Article schema with an explicit author entity gives Claude’s retrieval layer structured signals it can resolve without inference.

Verifiable claims backed by primary sources. Claude is conservative with citations and avoids asserting things it cannot confirm. Pages that link to original research, official documentation, and named experts are cited more readily than pages making unsupported claims, even where the underlying information is accurate. Linking out to credible sources is a direct citation signal, not just good editorial practice.

Passage-level structure. Claude cites at the passage level rather than the page level. A well-structured paragraph can earn a citation from an otherwise unremarkable page. Each section should be self-contained and open with a sentence that directly answers the question the heading implies. Answers buried mid-paragraph are extracted less reliably than those that lead.

Neutral, informational register. Claude avoids content that advocates for a position rather than informs. Promotional language, superlative-heavy product pages, and listicles that rank without defending criteria are cited less often than editorial content written in a factual, balanced tone.

How do you optimise for Claude citations?

1. Verify Brave indexing. Search for your key pages on Brave directly. If they do not appear for relevant queries, Claude is unlikely to surface them regardless of other signals. Brave offers a Web Discovery Project for publishers to submit sites for indexing.

2. Allow Claude-SearchBot in robots.txt. If you have historically blocked all AI crawlers or applied wildcard rules, verify that Claude-SearchBot is not inadvertently blocked. Each Anthropic user agent must be managed independently.⁵

3. Establish author entities in schema. Add author markup to Article schema with sufficient structured data for Claude to resolve the author: name, a url pointing to a personal site or profile, and sameAs links to LinkedIn or institutional pages where relevant.

4. Write for passage extraction. Open each H2 and H3 section with one or two sentences that directly answer the question the heading raises. Long preambles before the substantive answer reduce the chance of that passage being selected.

5. Cite primary sources outbound. Link to original research, official documentation, and named experts. Claude’s citation behaviour favours sources that themselves demonstrate editorial rigour.

6. Build authority through traditional means. Editorial backlinks, brand recognition, and original content all improve Brave rankings, which is the prerequisite for Claude visibility. The same off-page work that improves Google rankings improves Brave rankings, though relative weighting differs between the two indexes.

How do you measure Claude visibility?

There is no Claude equivalent of Google Search Console. The most direct available signal is referrer tracking: sessions from Claude appear in analytics with claude.ai as the referrer. As of May 2026, Google Analytics 4 aggregates traffic from major AI tools including Claude into a dedicated ‘AI Assistant’ channel, making this visible without custom configuration.⁶

For proactive measurement, manual sampling is the most reliable approach. Run representative queries for your niche in Claude and record which sources are cited. For brand-sensitive queries, tracking this periodically gives a directional indicator of how well your content is indexed and trusted within Claude’s retrieval pipeline.

Frequently asked questions

Does blocking ClaudeBot affect Claude citations?
No. ClaudeBot is the training crawler only. The crawler relevant to citation visibility is Claude-SearchBot.

If my site ranks well on Google, will Claude cite it?
Not automatically. Google and Brave rankings correlate imperfectly. A page can rank on the first page of Google and not appear in Brave for the same query. Checking Brave directly is the only reliable way to confirm indexing status.

Is Claude a significant traffic source?
Referral volumes from claude.ai are currently smaller than from Perplexity or ChatGPT Search for most sites. The more immediate value is visibility with technical and professional audiences, who use Claude at above-average rates relative to the general search population.

Does Claude use Google’s index at all?
Not by way of Brave’s web results, which come from Brave’s own index; Brave removed its remaining Bing API calls in April 2023.⁴ One nuance often stated too strongly: Brave does still offer Google Fallback mixing in its consumer search product, but it is an opt-in setting a user can enable, not a default, and it is a property of the consumer product rather than of the index Claude queries.⁴ For content strategy the conclusion is unchanged: get indexed by Brave.

Footnotes

1. Claude web search now available globally on all plans — Anthropic ↩

2. Anthropic appears to be using Brave to power web search for its Claude chatbot — TechCrunch ↩ ↩²

3. Does Anthropic crawl data from the web, and how can site owners block the crawler? — Anthropic Help Center ↩ ↩² ↩³

4. Brave Search removes last remnant of Bing from search results page — Brave ↩ ↩² ↩³

5. Anthropic clarifies how Claude bots crawl sites and how to block them — Search Engine Land ↩

6. New AI Assistant traffic measurement — Google Analytics ↩