# Program Streams Overview

> Receive Solana program instructions and events through gRPC.

Canonical: https://nolimitnodes.com/docs/api-reference/program-streams/overview

Program Streams preserve each program's instruction args, accounts, and event fields.

The catalog contains 1,074 topics across 37 Solana programs.

## Endpoint

```text
events.nln.clr3.org:443
```

Use TLS. Send `x-api-key` as gRPC metadata.

## Service methods

| Method | Purpose |
|---|---|
| `ListTopics` | Return topics allowed for your credential |
| `GetTopicSchema` | Return the program proto and payload message type |
| `Subscribe` | Open a server stream for one topic |

## Topic format

Topics use:

```text
solana..
```

Examples:

```text
solana.pump_fun.trade_event
solana.raydium_amm_v4.swap
solana.kamino_lending.deposit
```

## Response envelope

```protobuf
message SubscribeResponse {
  string topic = 1;
  uint64 slot = 2;
  string payload = 5;
}
```

JSON output stores decoded JSON text in `payload`.

PROTO output stores base64-encoded protobuf bytes in `payload`.

  ### [Quickstart](/docs/api-reference/program-streams/quickstart)

List topics, fetch a schema, and subscribe.

  ### [Program catalog](https://nolimitnodes.com/products/program-streams)

Browse all program and topic pages.