# Particle Pro: List Topics for Episode

> Particle Pro: List Topics for Episode is a paid API for AI agents from api.particle.pro, paid per call via x402, $0.03/call, status unknown (last checked 2026-09-13).

Returns the topic taxonomy classifications assigned to a specific podcast episode.

## Facts

- Endpoint: GET https://api.particle.pro/v1/podcasts/episodes/:id/topics
- Price: $0.03/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-13
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/particle-pro-list-topics-for-episode-0c017d1d
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_nvBY3QAmsJ-DGK7LXzu1d

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-topics-for-episode-0c017d1d
```

Example prompt: What topics does the Particle Pro API classify for the podcast episode with ID 'lex-fridman-elon-musk-2024'?

## When to prefer this

Use this endpoint when you need structured topic or subject classifications for a specific podcast episode — for example, to power content recommendation engines, build topic-filtered feeds, or enrich episode metadata. Prefer this over general episode search when you already have the episode ID or slug and need its taxonomy labels specifically.

## Known failure modes

- Episode ID or slug not found returns a 404 error
- Invalid pagination cursor returns an error or empty result
- Missing required path parameter 'id' causes a 400 bad request
- Payment failure or missing x402 payment header results in 402 Payment Required
- Rate limiting may result in 429 Too Many Requests

## How this service works

List topics for an episode. Returns the topic taxonomy classifications for a specific episode.

## Output

A list of topic taxonomy classifications for the specified episode, including topic labels and category identifiers. Results may be paginated using a cursor when a limit is specified.

## 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": "Episode slug or ID"
      }
     }
    },
    "queryParams": {
     "type": "object",
     "properties": {
      "limit": {
       "type": "integer",
       "format": "int64",
       "description": "Results per page (default: all)"
      },
      "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-topics-for-episode-0c017d1d/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)