# Particle Pro – List Publishers for a Sponsor

> Particle Pro – List Publishers for a Sponsor is a paid API for AI agents from api.particle.pro, paid per call via x402, $0.03/call, status unknown (last checked 2026-09-14).

Returns the podcast publishers where a given sponsor advertises, ordered by the number of distinct podcasts they appear on across each publisher.

## Facts

- Endpoint: GET https://api.particle.pro/v1/podcasts/advertising/sponsors/:id/publishers
- Price: $0.03/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/particle-pro-list-publishers-for-a-sponsor-1b5c8802
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_Bq6ndEjUox9q6gS2PKWLJ

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 particle-pro-list-publishers-for-a-sponsor-1b5c8802
```

Example prompt: Show me all the podcast publishers that HubSpot advertises with, ordered by how many of their podcasts carry HubSpot ads — use the company domain 'hubspot.com' as the sponsor ID.

## When to prefer this

Use this endpoint when you need to understand which podcast publisher networks a specific brand or sponsor buys advertising across, particularly when you want the coverage ranked by publisher breadth. Prefer this over the per-podcast sponsor list when the goal is publisher-level aggregation rather than episode-level detail. It is especially useful for competitive analysis, media planning, and publisher outreach prioritization.

## Known failure modes

- Sponsor ID / company domain not found – 404 with no results returned
- Ambiguous identifier resolves to multiple companies – may aggregate unexpectedly across multiple sponsors
- Invalid cursor value causes pagination error
- Rate limiting or payment failure via x402 protocol returns 402 or 429
- Empty result if sponsor has no recorded podcast advertising

## How this service works

List publishers for a sponsor. Returns the podcast publishers a sponsor advertises across, ordered by podcast coverage (the count of distinct publisher podcasts where the sponsor appears).

## Output

A paginated list of podcast publishers where the specified sponsor has placed advertising, each entry including publisher details and the count of distinct podcasts within that publisher carrying the sponsor's ads, sorted descending by podcast coverage. Includes an opaque cursor for fetching subsequent pages.

## 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"
     ],
     "type": "string"
    },
    "pathParams": {
     "type": "object",
     "required": [
      "id"
     ],
     "properties": {
      "id": {
       "type": "string",
       "description": "Sponsor ID, company ID, company domain, or company slug. When the value resolves to a company (not a specific sponsor), the response aggregates across every sponsor linked to that company — the canonical 'where does this advertiser buy?' view. When it resolves to a sponsor ID, the response is scoped to that single deduped sponsor."
      }
     }
    },
    "queryParams": {
     "type": "object",
     "properties": {
      "limit": {
       "type": "integer",
       "format": "int64",
       "description": "Results per page"
      },
      "cursor": {
       "type": "string",
       "description": "Opaque pagination cursor from previous response"
      }
     }
    }
   },
   "additionalProperties": false
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/particle-pro-list-publishers-for-a-sponsor-1b5c8802/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.particle.pro](https://www.zero.xyz/host/api.particle.pro/llms.txt)