> ## Documentation Index > Fetch the complete documentation index at: https://docs.playapi.ai/llms.txt > Use this file to discover all available pages before exploring further. # Gemini streamGenerateContent > Native SSE text and function calls. `POST /v1beta/models/{model}:streamGenerateContent?alt=sse` Send the gateway token in `x-goog-api-key` and select SSE with `alt=sse`. The request shape matches nonstreaming generateContent, but uses a different path action; a Chat-style `stream` body field is not a substitute. Each SSE data payload contains a Gemini response. Text and function calls appear in candidate content parts. Check prompt feedback, candidate indices, and the final finish reason; EOF alone is insufficient. Declare tools through `tools[].functionDeclarations` and return results as `functionResponse`. [The complete Python SSE and tool-loop example](/en/guides/native-gemini-streaming) covers both run modes, signature preservation, optional ID association, and failures. This schema expands common fields only, without guaranteeing Live API, fine-grained argument extensions, or support on every channel. [阅读中文](/zh/api-reference/gemini-stream) ## Media content parts Native `contents[].parts[]` can contain `inlineData: {mimeType, data}` or `fileData: {mimeType, fileUri}`; inline data is plain Base64. The target upstream must support the format and source. `videoMetadata` and `mediaResolution` are conditional native extensions, not a universal gateway transcoding or frame-extraction service. Media input does not change the response protocol or completion checks. The audited gateway scope provides no Gemini Files upload/management or Interactions endpoints; SDK auto-upload introduces extra unsupported requests. Start with the [complete non-streaming video example](/en/guides/video-understanding); streamed output still follows this endpoint's SSE events. ## Built-in metadata in SSE The request accepts the same conditional native `googleSearch`, `urlContext`, and `codeExecution` tool fields. Native SSE forwards upstream JSON events. Retain candidate metadata and code/result parts across events; do not flatten all events into plain text or assume each event contains a complete grounding record. The existing text/function SSE sample does not implement these built-in consumers. Start with the [non-streaming built-in example](/en/guides/gemini-builtins); native byte offsets and source association need protocol-aware accumulation before adding streaming. ## OpenAPI ````yaml openapi/relay.json POST /v1beta/models/{model}:streamGenerateContent openapi: 3.0.3 info: title: API — Core inference API version: 0.5.0 description: >- 面向接入的精选规范，不是全部管理或供应商接口。 / Curated integration specification, not the entire management or provider API. license: name: AGPL-3.0-or-later servers: - url: https://gateway.example.com description: >- Example only; replace with your gateway origin and optional path prefix, without /v1. security: - BearerAuth: [] paths: /v1beta/models/{model}:streamGenerateContent: post: summary: Gemini 原生流式生成 / Native Gemini streaming generation description: >- 原生 SSE；每个 data 包含 Gemini 响应对象。完成状态与工具处理见指南。 / Native SSE; each data payload is a Gemini response object. See the guide for completion and tool handling. operationId: streamGeminiContent parameters: - name: model in: path required: true description: >- 裸模型 ID，不含 models/ 和动作后缀 / Bare model ID without models/ or an action suffix. schema: type: string example: YOUR_MODEL_ID - name: alt in: query required: true schema: type: string enum: - sse description: 选择 SSE 传输 / Select SSE transport. requestBody: required: true content: application/json: schema: type: object required: - contents properties: contents: type: array minItems: 1 items: type: object properties: role: type: string parts: type: array items: type: object properties: text: type: string thought: type: boolean thoughtSignature: type: string functionCall: type: object properties: id: type: string name: type: string args: type: object additionalProperties: true additionalProperties: true functionResponse: type: object properties: id: type: string name: type: string response: type: object additionalProperties: true additionalProperties: true inlineData: type: object required: - mimeType - data properties: mimeType: type: string example: video/mp4 data: type: string description: >- 纯 Base64，不带 Data URL 前缀 / Plain Base64, no Data URL prefix description: >- 原生内联媒体，格式与大小依模型 / Native inline media; model-dependent formats and limits fileData: type: object properties: mimeType: type: string fileUri: type: string description: >- 上游可访问的 URI；不是网关上传服务 / Upstream-accessible URI, not a gateway upload service videoMetadata: type: object additionalProperties: true description: >- 模型依赖的原生扩展；请核对实际上游结构 / Model-dependent native extension; verify the upstream structure mediaResolution: type: object additionalProperties: true description: >- 模型依赖的原生扩展；请核对实际上游结构 / Model-dependent native extension; verify the upstream structure executableCode: type: object properties: language: type: string example: PYTHON code: type: string additionalProperties: true codeExecutionResult: type: object properties: outcome: type: string description: 检查 OUTCOME_OK / Check OUTCOME_OK output: type: string additionalProperties: true additionalProperties: true additionalProperties: true systemInstruction: type: object properties: role: type: string parts: type: array items: type: object properties: text: type: string thought: type: boolean thoughtSignature: type: string functionCall: type: object properties: id: type: string name: type: string args: type: object additionalProperties: true additionalProperties: true functionResponse: type: object properties: id: type: string name: type: string response: type: object additionalProperties: true additionalProperties: true additionalProperties: true additionalProperties: true tools: type: array items: type: object properties: functionDeclarations: type: array items: type: object required: - name properties: name: type: string description: type: string parameters: type: object additionalProperties: true description: >- 工具参数 Schema；示例额外执行本地校验 / Tool parameter schema; examples also validate locally. additionalProperties: true googleSearch: type: object additionalProperties: true description: >- 以空对象启用；依赖原生模型及渠道支持 / Enable with an empty object; native model and channel support required example: {} urlContext: type: object additionalProperties: true description: >- 以空对象启用；依赖原生模型及渠道支持 / Enable with an empty object; native model and channel support required example: {} codeExecution: type: object additionalProperties: true description: >- 以空对象启用；依赖原生模型及渠道支持 / Enable with an empty object; native model and channel support required example: {} additionalProperties: true additionalProperties: true responses: '200': description: >- 检查候选结束状态并处理流内错误 / Validate candidate finish status and in-stream errors. content: text/event-stream: schema: type: string default: description: >- 网关或上游错误，结构可能随协议变化 / Gateway or upstream error; structure may vary by protocol. content: application/json: schema: type: object additionalProperties: true security: - GeminiApiKey: [] - BearerAuth: [] components: securitySchemes: BearerAuth: type: http scheme: bearer description: 模型调用 API Key，不是控制台登录凭据 / Model API key, not console login credentials GeminiApiKey: type: apiKey in: header name: x-goog-api-key description: 网关令牌 / Gateway token ```` This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.