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name: discovery.hugen.tokyo
description: discovery.hugen.tokyo provides a searchable catalog of approximately 2,400 verified x402 APIs. Agents can query by keyword or category to retrieve ranked results including endpoint URLs, descriptions, pricing, network, quality scores, and broker call hints. It does not execute API calls itself.
host: discovery.hugen.tokyo
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# discovery.hugen.tokyo

Hugen Discovery is a directory and search service for the x402 API ecosystem. It serves agents that need to locate an appropriate x402 API before invoking it, covering domains such as AI/LLM, DeFi, weather, and more. Its distinguishing function is returning structured metadata — including broker call hints — that an agent can use to route a subsequent API call via the x402-pay SDK or broker endpoint.

## When to use this host

Use this host when an agent needs to find an x402 API to call but does not yet know the endpoint URL — for example, searching for a 'token security' or 'weather' API. The returned broker call hints and URLs can then be passed to the x402-pay SDK or a broker endpoint (POST /broker/call) for actual execution. Do not use this host to execute API calls, retrieve live data, or check API health; those actions require the target API's own endpoint. If the agent already knows the API endpoint it needs, skip this host entirely.

## Capabilities

### API Discovery

Searches and browses the x402 API catalog by keyword and/or category, returning ranked results with all metadata needed to identify and subsequently invoke a matching API.

- **`search-x402-apis`** — Searches a catalog of ~2,400 verified x402 APIs by keyword and/or category, returning ranked results with URL, description, price, network, category, quality score, and broker call hints.

## Skill reference

### `search-x402-apis`

**Hugen Discovery Search** — Searches a catalog of ~2,400 verified x402 APIs by keyword and/or category, returning ranked results with URL, description, price, network, category, quality score, and broker call hints.

*Use when:* Use when an agent needs to discover available x402 APIs by topic (e.g. 'weather', 'DeFi token security') or category (e.g. 'AI/LLM', 'DeFi'), or when browsing a diverse sample of APIs without a specific query.

*Not for:* Do not use to call or proxy an x402 API — use the broker endpoint (POST /broker/call) or x402-pay SDK for that. Not suitable for real-time price feeds or live API health checks.

**Inputs:**

- `q` (string) — Search keywords (e.g. 'weather forecast', 'defi token security'). Empty string returns a diverse sample across categories.
- `category` (string) — Category filter to narrow results (e.g. 'DeFi', 'Weather', 'AI/LLM').
- `limit` (integer) — Maximum number of results to return, between 1 and 20. Defaults to 10.

**Returns:** Returns total_results count, a ranked array of up to 20 API entries (url, description, price, network, category, quality_score, brokerable), and call_via instructions for invoking brokerable results.

**Example:** `GET https://discovery.hugen.tokyo/discovery/search?q=defi+token+security&category=DeFi&limit=5`

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