Create Context Cache cachedContents [Native Format]

Gemini Context Caching create endpoint; request/response follow Google's native cachedContents format. Suited to caching long documents or large system prompts, which can then be referenced via the cachedContent field in subsequent generateContent requests to save input tokens.

Limitations: model is required (models/xxx is accepted); at least one of contents or systemInstruction must be provided; image parts support URLs only; this site only exposes POST create, GET/PATCH/DELETE cache management is not available; Vertex channels are supported only in service-account mode. Billed according to the returned usageMetadata.

Source of truth in code: router/relay-router.go (relayGeminiRouter.POST("/cachedContents")), relay/gemini_handler.go, dto/gemini.go (GeminiCachedContentRequest).

Last verified/modified: 2026-09-28 (API Base URL unified to https://api.crazyrouter.com; example model names follow what GET /v1/models returns); tested: missing contents returns 400 invalid_request_params, missing model returns 400 "Model name is required"; gemini-2.5-pro is in the catalog

Provide your bearer token in the

Authorization

header when making requests to protected resources.

Example:

Authorization: Bearer ********************

curl --location 'https://api.crazyrouter.com/v1beta/cachedContents' \ --header 'x-goog-api-key: YOUR_API_KEY' \ --header 'Authorization: Bearer <token>' \ --header 'Content-Type: application/json' \ --data '{ "model": "gemini-2.5-pro", "displayName": "contract-cache", "ttl": "3600s", "contents": [ { "role": "user", "parts": [ { "text": "<very long document text>" } ] } ] }'

{ "name": "cachedContents/abc123def456", "model": "models/gemini-2.5-pro", "displayName": "contract-cache", "createTime": "2026-09-28T08:00:00Z", "updateTime": "2026-09-28T08:00:00Z", "expireTime": "2026-09-28T09:00:00Z", "usageMetadata": { "totalTokenCount": 18342 } }

Create Context Cache cachedContents [Native Format]

Request

Responses