Keyword research with Claude and Codex: use real SEO data

Claude and Codex can suggest keywords, but search-volume numbers need a source. Connect a keyword API such as Cite42 and you can ask your assistant to compare demand, explain the results and help choose what to write.

Cite42’s keyword tool returns monthly search volume, cost per click and paid-search competition. It uses Google Ads Keyword Planner, with DataForSEO as a fallback. MCP lets your assistant call these tools; the REST API lets scripts use the same data.

SEO still matters in AI search

Google’s AI search guidance says SEO fundamentals still apply to AI Overviews and AI Mode. Supporting pages must be indexed and eligible for a search snippet. No special AI markup is required.

Keep pages crawlable, link them clearly and answer useful questions in readable text. Google also uses related searches when assembling answers, so specific supporting pages can matter. That guidance covers Google; good SEO doesn’t guarantee citations across every assistant.

Connect Cite42 to Claude or Codex

In Claude web or Desktop, add a custom connector at https://mcp.cite42.dev, sign in to Cite42 and enable it in your conversation. Anthropic’s connector instructions cover the interface and organization permissions.

For Claude Code or Codex CLI, you’ll need Node.js 18+ and a key from API Keys. Add the local MCP package with the command for your client.

Claude Code:

claude mcp add cite42 --env CITE42_API_KEY=cite42_live_your_key_here -- npx -y @cite42/mcp

Codex CLI:

codex mcp add cite42 --env CITE42_API_KEY=cite42_live_your_key_here -- npx -y @cite42/mcp

Replace the example key locally, keep it out of shared files and start a new session. See the Claude Code, Codex or Cite42 setup instructions for details. Ask the assistant to show your balance and current prices before making paid calls; both lookups are free.

Compare two keywords

Tell the assistant what you sell, who buys it and which country to research. These examples use a fictional invoicing product. The search volumes and CPC figures are illustrative, not live research.

You ask your AIWe sell recurring-invoice software to UK freelancers. Compare “recurring invoice software” and “free invoice template” in Cite42 for the UK. Show the price and wait for approval, then report each term’s volume, CPC and paid competition.

Cite42Keyword comparison

Your AI saysIllustrative results · UKrecurring invoice software260monthly searchesCPC: $4.10Paid competition: mediumfree invoice template8,100monthly searchesCPC: $1.20Paid competition: highI’d investigate “recurring invoice software” first. It fits what you sell. The larger template query may attract people who only want a free document.These competition labels describe advertisers. They don’t measure organic ranking difficulty.

Keep the country setting consistent across your shortlist. Save the results with the research date so you can reuse them without paying for another lookup.

What the keyword numbers mean

Google’s historical metrics use average monthly searches over 12 months and group close variants. Averages can hide seasonal peaks, and spelling variations aren’t necessarily separate audiences. CPC describes advertising costs; it doesn’t predict your page’s revenue.

Missing volume deserves its own label. Cite42 can return broader alternatives, but their numbers belong to those terms.

You ask your AICheck “recurring invoices for freelance translators” in the UK. If there’s no data, say so. Keep any broader alternatives separate instead of borrowing their numbers.

Cite42Keyword lookup

Your AI saysIllustrative results · UKYour exact phraserecurring invoices for freelance translatorsNo search-volume data availableBroader alternativerecurring invoices1,000 monthly searchesThe broader term’s volume doesn’t establish demand for the translator-specific phrase. We could still cover translators as a use case if customer questions support it.

Trend data can help with timing, but relative interest and monthly search counts measure different things. Keep their units separate.

Turn the shortlist into a content brief

Check the current search results before committing to a term. Do searchers want a product, tutorial or download? A keyword API doesn’t answer that by itself. Choose a topic you can support with product facts or experience, and group phrases that answer the same question on one page.

Then ask for a brief using the saved research. The assistant can explain its recommendation without making another paid call.

You ask your AIUsing the saved results, recommend one topic and a short brief. Explain the tradeoff with the higher-volume phrase and what we still need to check. Don’t make more paid calls.

Uses saved research

Your AI saysIllustrative brief · No new paid callsRecurring invoice software for freelancersThe software query fits the product. The larger template query points toward a free download, which this page would not provide.Reader’s questionHow can I send repeat invoices without recreating them each month?Page promiseShow the recurring-invoice workflow, explain who it suits, and state its limits.Evidence to gatherActual product screenshots, supported billing schedules, and verified pricing.Before draftingInspect the UK search results to decide whether a product page or a tutorial would better answer the query.

After publishing, check Search Console queries, visits and useful customer actions. For the same questions in AI answers, keep a separate history with an AI visibility tracker.

Choose a keyword API

If you already use an SEO suite, check its connector first. Ahrefs SEO MCP is included on paid Lite, Standard, Advanced and Enterprise plans. It supports keyword, backlink and competitor research, with allowances set by the plan.

Cite42 suits occasional research you want to pay for by the call. A seed lookup costs $0.09 with volume data or $0.03 without it; requesting ideas costs $0.12. A batch of 2 to 50 keywords costs $0.09, or $0.03 when all volumes are zero or unavailable. See the pricing page for credit purchases.

Compare country coverage, missing-data handling and the cost of your actual research. If you need backlink analysis or technical audits, check those capabilities separately. A keyword endpoint only covers part of an SEO workflow.

Create a Cite42 account and check a shortlist for one page you’re considering. Use the data to choose the topic before spending time writing it.