# Streaming Parameter

Server-Sent Events delivery: the `stream` parameter, the frame shape and the termination markers.

The `stream` parameter enables Server-Sent Events (SSE) streaming for real-time response delivery.

**Type:** `boolean`
**Default:** `false` (non-streaming)

Example:
```bash
curl "https://mdapi.io/?input=...&stream=true"
```

Response format (OpenAI-compatible SSE, one JSON object per `data:` line):
```json
data: {"type":"token_info","token_status":"valid","token_balance":0.99,"token_expires":1798761600}
data: {"type":"products","parts":{...},"attachments":[...]}   // only when the request produced an index
data: {"choices":[{"index":0,"delta":{"content":" chunk"},"finish_reason":null}]}
data: {"choices":[{"index":0,"delta":{"content":" more"},"finish_reason":null}]}
data: {"choices":[{"index":0,"delta":{},"finish_reason":"stop"}]}
data: [DONE]
```

**Native streaming per protocol.** Every protocol delivers a *real* content stream when `stream: true`, but each emits it in its own native frame format (so existing clients keep working):

| Protocol         | Streaming frame format                                                                                                                                                                          |
| ---------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| REST             | OpenAI-compatible `choices/delta` frames                                                                                                                                                        |
| OpenAI           | `chat.completion.chunk` (`choices/delta`)                                                                                                                                                       |
| MCP              | `notifications/message` content chunks, then one final `tools/call` result frame                                                                                                                |
| ACP              | `session/update` notification chunks (one stable `messageId` per turn), then a final response carrying only `stopReason`                                                                        |
| A2A              | `result.task` (`TASK_STATE_WORKING`) start frame, `result.artifactUpdate` (`{artifact, append, lastChunk}`) content frames, then `result.statusUpdate` (`TASK_STATE_COMPLETED`) - stream closes |
| OpenAI Responses | SSE framed as Responses events - 9 events from `response.created` to `response.completed`                                                                                                       |

> **Note on MCP transport vs. the `stream` parameter.** The MCP manifest advertises `transport.type: "streamable-http"` - that is the MCP *transport*
> (how JSON-RPC requests are delivered to `POST /mcp`). It is unrelated to the `stream` *parameter*, which independently enables SSE streaming of the
> conversion **content**. You can use MCP without streaming; and when you do pass `stream: true`, the content arrives as SSE frames alongside the transport.

A stream that fails does not fake a clean end: after an error there is no `[DONE]` and no `finish_reason: "stop"`. The failure arrives in the protocol's own error frame - the OpenAI error envelope on the OpenAI endpoint, a JSON-RPC error object on MCP, ACP and A2A - and carries a stable code: `stream_error` for a failure while the content was being produced, `stream_timeout` when the model went quiet for too long. Branch on that code, not on the message.

```
data: {"error":{"message":"Stream error","type":"stream_error","param":null,"code":"stream_error","detail":"..."}}

data: {"jsonrpc":"2.0","id":1,"error":{"code":-32603,"message":"Stream error","data":{"code":"stream_error","detail":"..."}}}
```

The first is the OpenAI envelope (the REST `GET /` SSE path and `/v1/chat/completions`), the second the JSON-RPC object (MCP, ACP, A2A). On the Responses endpoint the frame is `{"type":"error","code":"stream_error","message":"Stream error","param":null}`. `message` and `detail` are free text and may change; only the code is a contract.

## Links

- **About service:** https://mdapi.io/about
- **API documentation and conversion:** https://mdapi.io
- **MCP server manifest:** https://mdapi.io/mcp
- **Health check:** https://mdapi.io/health
- **Documentation index:** https://mdapi.io/llms.txt
- **Full API documentation:** https://mdapi.io/llms-full.txt
- **AI discovery:** https://mdapi.io/.well-known/ai-discovery.json or https://mdapi.io/ai-discovery.json
- **AI Agent discovery:** https://mdapi.io/.well-known/agent.json or https://mdapi.io/agent.json
- **A2A Agent card:** https://mdapi.io/.well-known/agent-card.json or https://mdapi.io/agent-card.json
- **ACP manifest:** https://mdapi.io/.well-known/acp.json or https://mdapi.io/acp.json
- **x402 payment manifest:** https://mdapi.io/.well-known/x402.json or https://mdapi.io/x402.json
- **OpenAPI specification (JSON):** https://mdapi.io/.well-known/openapi.json or https://mdapi.io/openapi.json
- **OpenAPI specification (YAML):** https://mdapi.io/.well-known/openapi.yaml or https://mdapi.io/openapi.yaml
- **MAPI specification:** https://mdapi.io/.well-known/mapi.md or https://mdapi.io/mapi.md
- **Skill specification:** https://mdapi.io/.well-known/skill.md or https://mdapi.io/skill.md
- **Agent Plugins manifest:** https://mdapi.io/.well-known/plugin/plugin.json or https://mdapi.io/.well-known/plugin.json
- **Agent Plugins MCP config:** https://mdapi.io/.well-known/plugin/mcp.json
- **Agent Plugins conversion skill:** https://mdapi.io/.well-known/plugin/skills/mdapi-conversion/SKILL.md
- **API documentation pages:** https://mdapi.io/docs

## External Links

- **github.com** https://github.com/mdapiio/mdapi.io
- **skills.sh** https://www.skills.sh/mdapiio/mdapi.io
- **skillsmp.com** https://skillsmp.com/creators/mdapiio/mdapi.io
- **clawhub.ai** https://clawhub.ai/mdapiio
- **x.com** https://x.com/mdapiio

## Disclaimer

**The service is provided "AS IS".**


> mdapi.io is an edge-native service-transport primitive for AI, autonomous-agents, and the Web4 ecosystem.