# Related Keywords Expander

> Related Keywords Expander is a paid API for AI agents from seo.openverbs.com, paid per call via x402, $0.04/call, status unknown (last checked 2026-10-11).

Expands a seed keyword into a set of related keywords by traversing the related-searches graph, with control over depth, limit, language, and location.

## Facts

- Endpoint: POST https://seo.openverbs.com/v1/related-keywords?utm_source=zero.xyz
- Price: $0.04/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-11
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/related-keywords-expander-7e131bd4
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_zAsFtpxs9LKkRxNuZaAwl

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability related-keywords-expander-7e131bd4 -d '<json body>'
```

Example prompt: Can you expand the keyword 'coffee subscription' into up to 50 related keywords in English for the US market, going 2 levels deep into the related-searches graph?

## When to prefer this

Choose this endpoint when you need to discover and expand a seed keyword into a broader set of related search terms, especially when you need graph traversal depth control and localization by language and country. Prefer it over static keyword databases when you want dynamically generated related-search expansions tied to real search behavior. It is distinct from keyword metrics (which scores existing keywords) or keyword gap analysis (which compares against competitors).

## Known failure modes

- Invalid or unsupported language code returns validation error
- Unknown or invalid locationCode causes empty or error response
- Exceeding keyword maxLength (80 chars) returns validation error
- depth out of range (>4 or <0) returns schema validation error
- limit out of range (<1 or >100) returns schema validation error
- Payment failure or insufficient USDC balance blocks the call
- Very niche seed keywords with no related searches return empty list

## How this service works

Related keywords API - expand a seed keyword using Google's "searches related to" graph, returning the related keywords (traversed to a configurable depth) each with monthly search volume, CPC, competition, keyword difficulty and search intent, plus the further related terms branching off each. For content-cluster planning and keyword discovery. No matches returns empty results.

## Output

A list of related keywords derived by traversing the related-searches graph from the seed keyword, filtered by the specified depth, limit, language, and location. Each keyword represents a term users commonly search in relation to the seed.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "depth": {
   "type": "integer",
   "maximum": 4,
   "minimum": 0,
   "description": "How many levels of the related-searches graph to traverse (0-4). Defaults to 1."
  },
  "limit": {
   "type": "integer",
   "maximum": 100,
   "minimum": 1,
   "description": "Maximum keywords to return. Defaults to 20."
  },
  "keyword": {
   "type": "string",
   "maxLength": 80,
   "minLength": 1,
   "description": "Seed keyword to expand."
  },
  "languageCode": {
   "type": "string",
   "pattern": "^[A-Za-z]{2}$",
   "description": "Language code (2-letter). Defaults to en."
  },
  "locationCode": {
   "type": "integer",
   "description": "DataForSEO location code. Defaults to 2840 (United States)."
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/related-keywords-expander-7e131bd4/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from seo.openverbs.com](https://www.zero.xyz/host/seo.openverbs.com/llms.txt)