Xtrusio vs Surfer vs Clearscope vs Frase: Which Writes Content AI Engines Cite in 2026?

We took each Surfer, Clearscope and Frase fact from that vendor's pricing page or help docs on October 9, 2026, and editor plans get repriced, so look again before buying.

Why a content score is not a citation

Content optimizers were built for Google rankings. You enter a keyword, the tool reads the pages that rank for it, lists the terms those pages share, and grades your draft on how well it covers them. The target is the set of pages Google already ranks.

AI answer engines start somewhere else. A buyer asks a full question. The engine often searches the web before it answers, then reads a small set of pages and cites a few. In Xtrusio's checks, ChatGPT and Claude search the web on every answer; Gemini and Grok decide when to search. Those searches are often worded differently from the keyword you would have picked, and the cited pages are often not on your site: publications, Reddit, LinkedIn, YouTube and press coverage appear again and again.

So two questions matter more than any score:

1. What is the tool optimizing against? The pages that rank on Google, or the searches AI engines run and the pages they cite?
2. What does the tool count as done? A grade on a draft, or a citation in a real answer?

Content optimizers answer both with the draft. Xtrusio answers them with the engine: it plans from the searches the engines ran, places pieces on the sites they cite, and checks the exact URL in a later scan. For how this differs from classic SEO, see AEO vs GEO vs SEO.

Xtrusio: content planned from the engines' own searches

Xtrusio is our product, and we rank it first.

• The brief begins with buyer questions, not keywords. Your buyers' questions are put to ChatGPT, Claude, Gemini, Perplexity, Grok, Google AI Overviews and Google AI Mode, and Xtrusio files each answer whole, alongside the brands it mentions and the sources it cites, reporting visibility, share of voice and citations for every engine, topic and buyer persona.
• Search logs become the content brief. Xtrusio drafts the content plan from the searches the AI engines actually run. Whatever ChatGPT, Claude, Gemini and Grok search for, and whichever sites they already cite, feeds a content plan per buyer question that also picks each piece's channel among your blog, LinkedIn, Medium, Reddit, YouTube, guest posts and PR. Nothing is drafted until a strategist approves the plan.
• Written against a published standard. Each article is drafted and scored on Citation-Grade Content, the 78-check method Xtrusio coined, and no link goes through without a check before approval. Finished articles publish to your blog when it is connected, and each one is repurposed into press releases, Medium essays, YouTube scripts and LinkedIn post drafts.
• Placed where AI looks. Pieces can run across a network of about 2,000 publisher websites, with PR handled through Connectively, Featured, HARO and SourceBottle by a journalist team, and Link Strategy follows each placement until its URL is live.
• Judged on the citation. A page is verified only once an engine, asked its target question again in a later scan, names that exact URL as a source; you see the before and after on that same question.

What it costs: Free self-serve plan; managed service with a free trial, then tiered plans (details on request).

The 78 checks behind Citation-Grade Content

A content score asks whether your draft resembles the pages that rank. Citation-Grade Content (CGC) asks whether your page gives the most complete first answer to a buyer's question, so an AI engine has a reason to use and cite it. Seven families hold the 78 checks:

1. Answer first (10 checks). The title and opening 100 words resolve the question, and the title's form fits the intent: ranking, comparison, definition, how-to or verdict.
2. Verifiable evidence (10 checks). Each figure traces to verified proof or a named source found in research, and quotes match their source exactly.
3. Reader value and readability (16 checks). The piece teaches something your recent pieces have not, with clear headings, short paragraphs and no padding.
4. A natural brand win (11 checks). Your brand comes out ahead through depth and the buyer's own criteria, not through claims.
5. Links and citations (10 checks). Brand links are drawn only from a closed list that has been verified.
6. Answer tests (7 checks). Separate AI judges answer the buyer's question from a pool holding your page plus the pages engines cite today, and the check records which page they use and cite.
7. Destination fit and the quality gate (14 checks). Five criteria are scored by an assessor running on a different AI provider from the writer; a piece passes at 70 out of 100, and a score of 1 or lower on any criterion blocks it.

For the full method, read what Citation-Grade Content is.

Surfer: a live score against top-ranking pages

Use case: writers who want one number to aim for while drafting a page for a keyword.

Surfer's help docs describe Content Score as a 0 to 100 measure of how well a page is optimized compared to top-ranking content for the target query. It has two parts: an SEO Score for relevance, topical coverage, keyword usage and structure, and an AI Search Score for Facts Coverage and Upfront Intent Alignment, meaning whether the page answers the main question early.

Prices (billed monthly, or billed yearly): Discovery is $59 a month, or $49 billed yearly, for 120 documents, with no AI prompt tracking. Standard is $115 a month, or $99 billed yearly, for 360 documents and 25 prompts on ChatGPT, refreshed weekly. Pro ($211 a month, or $182 billed yearly) and Peace of Mind ($346, or $299 billed yearly) track 50 and 100 prompts across five AI platforms. Tracking on its own is sold as AI Search Analytics: $93 a month billed monthly, $82 billed yearly, 50 prompts.

The score is measured on the draft, against pages that already rank.

Clearscope: a letter grade for term coverage

Use case: editorial teams that want a simple grade non-SEO writers can follow.

Clearscope's support docs define Content Grade as its measure of relevance and comprehensiveness: the more of the most relevant terms a draft includes, the higher the grade. Each term is weighted by how much it appears in the top-ranking Google articles for the keyword, from 10 for a must-include term down to 1.

Prices: Essentials is $129 a month for 20 drafts, 50 pages and 50 tracked queries. Business is $399 a month for 300 tracked queries and 300 pages, still with 20 drafts a month. Enterprise is custom. Every plan has a 14-day free trial, query tracking across ChatGPT and Gemini, and a view of the web searches AI platforms run to build their answers.

The grade itself still scores term coverage against what ranks on Google, so the writer's target is the search results page, not the AI answer.

Frase: SEO and GEO scores in one editor

Use case: small content teams that want an on-page check for AI readability inside a writing tool.

Frase's docs describe two scores. The SEO score checks keyword placement, heading hierarchy, content depth and linking. The GEO score checks how easily AI systems can extract, understand and reference the page, looking at direct answers, structure and question coverage.

Prices: Starter costs $39 a month on yearly billing ($49 if paid monthly) for one site, 10 articles a month and AI Visibility on ChatGPT and Google AI. Professional is $103 billed yearly ($129 monthly) for 40 articles, adding Perplexity. Scale is $239 billed yearly ($299 monthly) for 100 articles, adding Claude and Gemini. Each plan starts with a 7-day free trial.

Frase can push drafts to WordPress, Webflow, Sanity or Wix; its pricing page also notes that AI Visibility does not auto-fix.

How will you know a content tool worked?

Run the same test on any tool:

1. Write down 10 questions your buyers put to AI before purchasing.
2. Ask the engines those questions and save the full answers and cited pages.
3. Ask the tool what it optimizes each piece against: a keyword's ranking pages, or the engine's own searches and cited pages.
4. Publish or place the pieces.
5. Put the same 10 questions to the engines again and look for your exact page among the citations.

A tool that stops at step 3 helps you write a draft. Xtrusio is built to carry all five steps, and counts only step 5 as a win.

Read what Xtrusio's service plans include, and begin with the questions your buyers ask AI.