# Particle Pro – List Episode Entities

> Particle Pro – List Episode Entities 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 knowledge graph entities (people, organizations, topics, etc.) mentioned in a specific podcast episode, with salience scores and occurrence counts.

## Facts

- Endpoint: GET https://api.particle.pro/v1/podcasts/episodes/:id/entities
- 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-episode-entities-67ba2bef
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_jFdIc1kODIjAg2piLCxZ9

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-episode-entities-67ba2bef
```

Example prompt: Can you pull up all the entities mentioned in podcast episode 'episode-2024-07-15-daily-brief' on Particle Pro, along with their salience scores and how often each one came up?

## When to prefer this

Use this endpoint when you need structured, scored entity data for a specific podcast episode — particularly useful for political intelligence, media monitoring, topic research, or building knowledge graphs from podcast content. Prefer this over general NLP APIs when you want pre-computed salience and occurrence data from Particle Pro's podcast index without running your own NER pipeline.

## Known failure modes

- Episode ID not found — returns 404 if the slug or ID does not match any indexed episode
- Invalid cursor — pagination cursor is malformed or expired, returning an error
- Rate limiting or payment failure — x402 payment not accepted, returning 402 Payment Required
- Empty results — episode exists but has not been entity-analyzed yet
- Malformed limit parameter — non-integer or out-of-range value causes a 400 error

## How this service works

List entities in an episode. Returns knowledge graph entities mentioned in a specific episode, with salience scores and occurrence counts.

## Output

A list of knowledge graph entities detected in the specified episode, each annotated with a salience score (indicating how central/prominent the entity was) and an occurrence count (how many times it was mentioned). Response may be paginated via an opaque cursor for large entity sets.

## 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-episode-entities-67ba2bef/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)