Keyword Research API
SEO keyword research -- Google Suggest, intent classification, long-tail discovery, related queries. Content planning. Pay-per-call via x402 (USDC on Base L2) -- no API key, no signup, no rate-limit wall.
Part of the klymax402 marketplace -- 100 x402 micropayment APIs for AI agents, one wallet, USDC on Base.
Quickstart -- MCP
Add to your MCP client config (Claude Desktop, Cursor, ElizaOS, etc.):
{
"mcpServers": {
"keyword-research": {
"url": "https://keyword-research.api.klymax402.com/mcp"
}
}
}
Quickstart -- HTTP (x402)
curl "https://keyword-research.api.klymax402.com/api/keywords?query=..."
# -> 402 Payment Required, with an x402 payment challenge in the response body
Any x402-aware client (@x402/fetch, x402-agent-tools, ATXP) handles the 402 -> sign -> retry cycle automatically.
Tools
| Tool | Method | Path | Price | Description |
|---|---|---|---|---|
seo_research_keywords | GET | /api/keywords | $0.02 | Research keywords with Google autocomplete suggestions, related queries, and intent classification |
seo_research_keywords | POST | /api/keywords | $0.02 | Research keywords with Google autocomplete suggestions, related queries, and intent classification (POST variant) |
seo_research_keywords
Use this when you need keyword ideas, SEO research, or content planning data for a topic. Returns keyword suggestions and intent data in JSON.
Parameters
| Name | Type | Required | Description |
|---|---|---|---|
query | string | yes | The seed keyword or phrase to research (e.g. 'bitcoin trading', 'best crm software') |
Example response:
{"query":"bitcoin trading","suggestions":["bitcoin trading platform","bitcoin trading bot","bitcoin trading for beginners"],"relatedQueries":{"vs":["bitcoin trading vs investing"],"howTo":["how to start bitcoin trading"]},"longTailKeywords":["best bitcoin trading app 2026","bitcoin trading strategy for beginners"],"searchIntent":"commercial","totalKeywords":47}
When to use: writing blog posts, FOR SEO content strategy, topic cluster planning, content gap analysis, and competitive keyword research.
Not for: page SEO audit (use seo_audit_page), content extraction (use web_scrape_to_markdown), domain intelligence (use domain_lookup_intelligence).
seo_research_keywords
Use this when you need keyword ideas, SEO research, or content planning data for a topic. Returns keyword suggestions and intent data in JSON. POST variant of seo_research_keywords -- same params passed as JSON body instead of query string.
Parameters
| Name | Type | Required | Description |
|---|---|---|---|
query | string | yes | The seed keyword or phrase to research (e.g. 'bitcoin trading', 'best crm software') |
Example response:
{"query":"bitcoin trading","suggestions":["bitcoin trading platform","bitcoin trading bot","bitcoin trading for beginners"],"relatedQueries":{"vs":["bitcoin trading vs investing"],"howTo":["how to start bitcoin trading"]},"longTailKeywords":["best bitcoin trading app 2026","bitcoin trading strategy for beginners"],"searchIntent":"commercial","totalKeywords":47}
When to use: writing blog posts, FOR SEO content strategy, topic cluster planning, content gap analysis, and competitive keyword research.
Not for: page SEO audit (use seo_audit_page), content extraction (use web_scrape_to_markdown), domain intelligence (use domain_lookup_intelligence).
Example agent prompts
- "Keyword ideas, SEO research, or content planning data for a topic"
- "Keyword ideas, SEO research, or content planning data for a topic"
Payment
- Protocol: x402 -- HTTP-native pay-per-call, no signup, no API key
- Network: Base L2 (
eip155:8453) - Asset: USDC
- Facilitator: Coinbase CDP (primary), PayAI (fallback)
- Also reachable via ATXP (OAuth-wrapped x402, RFC 9728 protected-resource metadata)
Part of klymax402
100 x402 micropayment APIs for AI agents -- one wallet, USDC on Base, zero signup.
- Catalog: https://klymax402.com/llms.txt
- Full API reference: https://klymax402.com/llms-full.txt
- Live stats: https://klymax402.com/stats
License
MIT