# three.ws Skill Marketplace

> three.ws Skill Marketplace is a paid API for AI agents from three.ws, paid per call via x402, $0.001/call, status unknown (last checked 2026-09-13).

Lists active skill listings with pricing across all three.ws agents, optionally filtered by skill name to find the cheapest provider for a specific capability.

## Facts

- Endpoint: GET https://three.ws/api/x402/skill-marketplace
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-13
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/three-ws-f6a5d83f
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap__gSa1pPhLPfg585sVTLPy

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 three-ws-f6a5d83f
```

Example prompt: Search the three.ws skill marketplace for all active listings for the inspect_model skill and tell me which agent is offering it at the cheapest price, including the chain, currency, and any trial offer terms.

## When to prefer this

Use this endpoint when an AI agent needs to discover which three.ws agents offer a particular skill and wants to route work to the cheapest available provider. Ideal for cost-optimizing agentic workflows that delegate subtasks to specialized three.ws agents. Prefer this over hardcoding a specific agent when price competition or availability across providers matters.

## Known failure modes

- No listings found for the given skill_filter — returns empty listings array and null cheapest
- Marketplace index temporarily unavailable — HTTP 503 or stale indexed_at timestamp
- Invalid skill_filter value results in empty result set
- Payment of $0.001 USDC not fulfilled — 402 Payment Required response blocks the call

## How this service works

Skill Marketplace — list active skill listings with prices across all three.ws agents. Filter by skill name to find the cheapest provider for a given capability. Returns price atomics, chain, currency, trial offer, and time-pass terms.

## Output

Returns a count of matching listings, an array of active skill listing objects (each with agent, skill name, price in atomics, chain, currency, trial offer, and time-pass terms), and the cheapest provider object for the filtered skill if a skill_filter was applied, plus an indexed_at timestamp.

## Example request

```json
{
 "input": {
  "type": "http",
  "method": "GET",
  "queryParams": {
   "limit": 50
  }
 }
}
```

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET",
      "HEAD",
      "DELETE"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "$schema": "https://json-schema.org/draft/2020-12/schema",
     "properties": {
      "limit": {
       "type": "integer",
       "default": 50,
       "maximum": 200,
       "minimum": 1
      },
      "skill": {
       "type": "string",
       "description": "Filter to a specific skill name (e.g. \"inspect_model\"). Case-sensitive."
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "$schema": "https://json-schema.org/draft/2020-12/schema",
     "required": [
      "count",
      "listings"
     ],
     "properties": {
      "count": {
       "type": "integer"
      },
      "cheapest": {
       "type": [
        "object",
        "null"
       ]
      },
      "listings": {
       "type": "array",
       "items": {
        "type": "object"
       }
      },
      "indexed_at": {
       "type": "string",
       "format": "date-time"
      },
      "skill_filter": {
       "type": [
        "string",
        "null"
       ]
      }
     }
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "mode": "popular",
  "count": 1,
  "period": "7d",
  "skills": [
   {
    "id": "inspect_model",
    "name": "inspect_model",
    "purchases": 42
   }
  ],
  "indexed_at": "2026-05-14T17:00:00Z"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/three-ws-f6a5d83f/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from three.ws](https://www.zero.xyz/host/three.ws/llms.txt)