Topical Authority Tool: Build the Map of Your Topic, Check Your Site's Coverage, Find the Missing Pages


A topical authority tool has to answer three questions: what does the whole topic look like, which parts of it does your site already cover, and which pages are missing. Most tools build the map from a keyword list and check coverage by matching your page titles or rankings against it. A knowledge graph does it from the text itself: one graph of what ranks and what AI answers say, one graph of your site, and the gaps between them are the pages to write.

InfraNodus does the graph version. It builds the map from the top search results, related queries and AI answers for your seed, compares it with the graph of your own pages using difference_between_texts, and turns each structural gap into a page brief with generate_content_gaps. It runs in the web app or from Claude Code through the InfraNodus MCP server. For what topical authority is and why search engines reward it, read the KeywordGraph guide; this page is about the tool.

A topic mapped as a knowledge graph: clusters are subtopics, the thin space between two clusters is a page nobody has written
 

Build Your Topical Authority Map

1
Create an Account

Sign up for a free InfraNodus account to get access to the knowledge graph tools and your API key.

Create a Free Account
2
Get InfraNodus MCP
https://mcp.infranodus.com

Add this URL as a connector via Settings > Connectors in Claude Web / Desktop and authenticate with your InfraNodus API key via OAuth.

3
Install the Skill
/plugin marketplace add infranodus/skills
/plugin install seo-analysis@infranodus-skills

Run these two commands in the Claude Code prompt to install the skill as a plugin (use infranodus-all@infranodus-skills to install all our skills at once). Or use npx in your terminal: 

npx skills add infranodus/skills --skill seo-analysis -g -a claude-code -y

npx comes bundled with Node.js. For ChatGPT and OpenClaw, see the full installation instructions.

Didn't work? You can simply download seo-analysis.zip from our GitHub repository and add it to your LLM client manually — see the step-by-step instructions.

4
Try It: Your First Prompt

Paste this into Claude Code, Claude Desktop, Cursor or any client where the skill is installed, or type /seo-analysis in Claude Code to call the skill by name. Replace the parts in square brackets with your own: 

Use the seo-analysis skill to build a topical authority map for [topic] from the top Google results, the related queries and the ChatGPT answers, then compare it with my site [url] and list the missing pages.

What a Topical Authority Tool Has to Show You

A topical authority tool shows you three things: the map of the topic (its subtopics and the concepts that connect them), your coverage (which subtopics your site already treats in depth), and the missing pages (the subtopics, and the links between them, that nobody on your site has written). A tool that stops at the map is a keyword tool with a diagram. The check against your own content is what makes it a topical authority tool.

OutputKeyword-list tools (Keyword Insights, TopicalMap.ai, RankDots, Search Atlas)Knowledge graph (InfraNodus)
The mapGenerated from a seed keyword and its related keywords, grouped by SERP similarity or by an AI prompt into pillars and clustersBuilt from the text of what ranks and what AI answers say; concepts connect when they co-occur, clusters are detected in the graph
Your coverageA completeness badge or a score from matching your page titles and rankings against the mapYour pages as a second graph; difference_between_texts shows which clusters of the field are absent or thin in your text
The missing pagesThe unmatched keywords in the map, often as a "next pages to write" listThe structural gaps between clusters on your site, each one a page that connects two subtopics you treat separately

The keyword-list tools do their job well. Keyword Insights clusters keywords by SERP overlap and shows which competitors are visible on each cluster. RankDots draws the map with a completeness indicator per branch. SEOPlugin's Topical Authority Mapper scores coverage from page titles and names the next three pages to write. None of them reads the text, so a title match counts as coverage even when the page skips the concepts that hold the cluster together.

Topical Authority with Ahrefs and Semrush: What the Gap Reports Give You

For the prompt "topical authority ahrefs": Ahrefs and Semrush give you the inputs. The Content Gap report lists keywords your competitors rank for and you do not, Keywords Explorer groups them into parent topics, and Search Console shows which of your pages get impressions for them. What they cannot show is the structure of your text against the topic: a gap report is a keyword list, and it does not say whether your pages form a cluster or stand alone.

Ahrefs finds the keyword gaps; the graph finds the structural gaps, the missing connections between topics you already cover. Paste the export into the field graph described below; the keywords take their place inside the clusters.

Build the Topical Authority Map as a Knowledge Graph

A topical authority map built as a knowledge graph is a network of the concepts that appear in the field, connected when they occur close to each other in the text. InfraNodus normalizes words to their base forms, links those that co-occur within a few words, and runs community detection: the densely connected groups are the topical clusters, and betweenness centrality marks the concepts that hold clusters together. For the strategy sense of the term, see KeywordGraph's topical map guide.

Four steps:

1. Import the search results

Run the Google search results app on your seed (analyze_google_search_results over MCP). InfraNodus fetches the titles and snippets of the top results and builds the first layer of the graph: what the ranking pages talk about.

2. Add the related queries

Add the related, long-tail and People Also Ask queries for the same seed (analyze_related_search_queries). This is the demand side: what people ask, grouped into search intent clusters, next to what the results supply.

3. Add what the AI answers say

Add the ChatGPT or Google AI Overview answers for the seed (analyze_llm_results). AI answers compress the field into the entities and claims they treat as canonical, and your site has to be cited next to them.

4. Read the clusters, then remove the top nodes

The graph now shows the topic as clusters with their central concepts. Remove the top layer of nodes (the seed and its obvious companions) to see the subtopics underneath, where the less obvious pages live. Save the graph; it is your field graph for this topic.

Topical clusters of the search results and related queries for one seed keyword, with the central concepts of each cluster
 

Check Your Coverage: the Topical Authority Checker

A topical authority checker compares the graph of your site with the graph of the field. Paste the text of your pages (or import the URLs of one sitemap section) as a second graph, then run difference_between_texts with your site as the first context and the field graph as the second: the tool reports what the first text lacks. The result, a list of the field's clusters that are thin or absent in your content, is the coverage report.

What counts as covered: a cluster is covered when its central concepts appear in your text and are connected to each other there, not when one page title contains the cluster's head keyword. Open the statements behind a cluster in both graphs to see the difference: in the field graph the concepts are discussed together; in yours, often only the head term appears.

Then run generate_content_gaps on your site graph. The structural gaps it finds between two clusters you already treat are the bridge pages. The same site graph shows cannibalization: two pages landing in one cluster compete for the same subtopic.

The site graph compared with the field graph: concepts present in the field and absent from the site are highlighted
 

Why Coverage Is What AI Answers Reward

When someone asks ChatGPT "how to rank in chatgpt", the answer names sources that cover a cluster of the question, not one page that matches the query. AI answers are assembled from several sources per subtopic, and a site that treats the cluster's connecting concepts gets pulled in for more of them. Coverage of the field's clusters, checked against your text, is the part you can measure. The long version is in how to rank in ChatGPT and AI search.

Because step 3 put the AI answers into the field graph, the gap list is already AI-aware: a cluster that only the AI answers mention, and that your site lacks, is a page AI search needs before Google asks for it. That is the "topical authority chatgpt" angle.

From the Gap List to the Content Plan

Each gap is a page brief: the two clusters it connects, the concepts the field uses to connect them, and the related queries that fall into it. Save each one to Project Notes as you go, then export the notes as the content plan. Hub and spoke structure is covered in SEO clusters, the keyword groups per spoke in keyword clustering for SEO.

Order the gaps by the demand of their related queries, or by how central the connecting concepts are in the field graph. Each bridge page links to the two cluster pages it connects, and that is the internal linking plan. Rerun the comparison after publishing; the covered count is your progress. From Claude Code, the SEO skill runs the whole sequence with a free InfraNodus account.


Get Started


Frequently Asked Questions

What is the best topical authority tool?

It depends where your map comes from. Keyword Insights and RankDots build maps from keyword lists and show coverage as a badge or score; they group thousands of keywords fast. InfraNodus builds the map from the text of the field and checks it against the text of your site with difference_between_texts, so it finds gaps a title match cannot.

Is there a free topical authority checker?

Yes. A free InfraNodus account lets you build the field graph from search results and related queries, add your own pages as a second graph, and run the comparison. Limits apply to graph size and searches per day, so start with one topic and one section of your site rather than the whole sitemap.

How do I build a topical authority map?

In the tool sense, InfraNodus is a topical authority map generator: import the top search results, the related queries and the AI answers for your seed into one graph, then read the topical clusters and their central concepts as the map. Remove the top nodes to see the subtopics underneath. For the strategy sense (pillars, clusters, internal links), read KeywordGraph's topical map guide.

Can I build topical authority with Ahrefs alone?

You can find the keywords with Ahrefs alone: Content Gap, Keywords Explorer and Site Explorer give you what competitors rank for and how the topic splits into parent topics. What Ahrefs does not show is whether your pages connect those keywords into a cluster. A graph of the export next to your own text shows that.

How do I check my topical authority score?

There is no single score; the ones tools show come from page titles and rankings. A more honest check is coverage per cluster: run difference_between_texts between your site graph and the field graph and count the clusters where your text has the central concepts connected. Eight clusters with five covered gives you a number you can defend and three pages to write.

Does topical authority help me get cited in ChatGPT?

Coverage of a topic's clusters is what AI answers select for, so yes, within limits: AI search also weighs freshness, named sources and whether your page states a claim plainly. Adding the AI answers to your field graph puts the clusters they rely on into your gap list. Turning that into pages ChatGPT cites is covered in SEO for LLMs and AI search.


 

Map Your Topic and See What You Have Not Covered


Build the field graph for one topic you want to own, add your site as the second graph, and read the clusters you cover, the ones you do not, and the gaps between them that nobody has written.


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