> ## Documentation Index > Fetch the complete documentation index at: https://docs.zeroentropy.dev/llms.txt > Use this file to discover all available pages before exploring further. # Rerank > Reranks the provided documents, according to the provided query. The results will be sorted by descending order of relevance. For each document, the index and the score will be returned. The index is relative to the documents array that was passed in. The score is the query-document relevancy determined by the reranker model. The results will be returned in descending order of relevance. Organizations will, by default, have a ratelimit of `500,000` bytes-per-minute (BPM) and `1000` requests-per-minute (RPM). Ratelimits are refreshed every 15 seconds. If this is exceeded, requests will be throttled into `latency: "slow"` mode, up to `5000000` bytes-per-minute. If even this is exceeded, you will get a `429` error. The "bytes" used by a request is calculated as `sum(150 + query.encode('utf-8') + d.encode('utf-8') for d in documents)`. Note a baseline overhead of `150` bytes, and that the query bytes are included for each document, as rerankers are cross-encoders. The maximum per-request payload size is `5000000` bytes. To increase your ratelimits, subscribe to a higher tier on the [ZeroEntropy dashboard](https://dashboard.zeroentropy.dev/billing). Any payments made for subscriptions in a calendar month will be deducted from your usage charges for that month. To request even higher ratelimits, please contact [founders@zeroentropy.dev](mailto:founders@zeroentropy.dev) or message us on [Discord](https://go.zeroentropy.dev/discord) or [Slack](https://go.zeroentropy.dev/slack)! ## OpenAPI ````yaml /api-reference/openapi.json post /models/rerank openapi: 3.1.0 info: title: ZeroEntropy API description: This API provides access to ZeroEntropy's SoTA retrieval pipeline. Enjoy! version: 0.1.0 servers: - url: https://api.zeroentropy.dev/v1 description: ZeroEntropy API - url: https://eu-api.zeroentropy.dev/v1 description: ZeroEntropy API (EU datacenters) security: [] paths: /models/rerank: post: tags: - Models summary: Rerank description: >- Reranks the provided documents, according to the provided query. The results will be sorted by descending order of relevance. For each document, the index and the score will be returned. The index is relative to the documents array that was passed in. The score is the query-document relevancy determined by the reranker model. The results will be returned in descending order of relevance. Organizations will, by default, have a ratelimit of `500,000` bytes-per-minute (BPM) and `1000` requests-per-minute (RPM). Ratelimits are refreshed every 15 seconds. If this is exceeded, requests will be throttled into `latency: "slow"` mode, up to `5000000` bytes-per-minute. If even this is exceeded, you will get a `429` error. The "bytes" used by a request is calculated as `sum(150 + query.encode('utf-8') + d.encode('utf-8') for d in documents)`. Note a baseline overhead of `150` bytes, and that the query bytes are included for each document, as rerankers are cross-encoders. The maximum per-request payload size is `5000000` bytes. To increase your ratelimits, subscribe to a higher tier on the [ZeroEntropy dashboard](https://dashboard.zeroentropy.dev/billing). Any payments made for subscriptions in a calendar month will be deducted from your usage charges for that month. To request even higher ratelimits, please contact [founders@zeroentropy.dev](mailto:founders@zeroentropy.dev) or message us on [Discord](https://go.zeroentropy.dev/discord) or [Slack](https://go.zeroentropy.dev/slack)! operationId: rerank_models_rerank_post requestBody: content: application/json: schema: $ref: '#/components/schemas/RerankRequest' required: true responses: '200': description: Successful Response content: application/json: schema: $ref: '#/components/schemas/RerankResponse' '404': description: Not Found content: application/json: example: detail: Description of Error '422': description: Validation Error content: application/json: schema: $ref: '#/components/schemas/HTTPValidationError' security: - HTTPBearer: [] components: schemas: RerankRequest: properties: model: type: string title: Model description: >- The model ID to use for reranking. Options are: ["zerank-2", "zerank-1", "zerank-1-small"] query: type: string title: Query description: The query to rerank the documents by. top_n: anyOf: - type: integer - type: 'null' title: Top N description: >- If provided, then only the top `n` documents will be returned in the results array. Otherwise, `n` will be the length of the provided documents array. documents: items: type: string type: array title: Documents description: The list of documents to rerank. Each document is a string. latency: anyOf: - type: string enum: - fast - slow - type: 'null' title: Latency description: >- Whether the call will be inferenced "fast" or "slow". RateLimits for slow API calls are orders of magnitude higher, but you can expect >10 second latency. Fast inferences are guaranteed subsecond, but rate limits are lower. If not specified, first a "fast" call will be attempted, but if you have exceeded your fast rate limit, then a slow call will be executed. If explicitly set to "fast", then 429 will be returned if it cannot be executed fast. type: object required: - model - query - documents title: RerankRequest RerankResponse: properties: results: items: $ref: '#/components/schemas/RerankResult' type: array title: Results description: The results, ordered by descending order of relevance to the query. total_bytes: type: integer title: Total Bytes description: >- The total number of bytes in the request. This is used for ratelimiting. total_tokens: type: integer title: Total Tokens description: The total number of tokens in the request. This is used for billing. actual_latency_mode: type: string enum: - fast - slow title: Actual Latency Mode description: >- The type of inference actually used. If `auto` is requested, then `fast` will be used by default, with `slow` as a fallback if your ratelimit is exceeded. Else, this field will be identical to the requested latency mode. e2e_latency: type: number title: E2E Latency description: >- The total time, in seconds, between rerank request received and rerank response returned. Client latency should equal `e2e_latency` + your ping to ZeroEntropy's API. inference_latency: type: number title: Inference Latency description: >- The time, in seconds, to actually inference the request. If this is significantly lower than `e2e_latency`, this is likely due to ratelimiting. Please request a higher ratelimit at [founders@zeroentropy.dev](mailto:founders@zeroentropy.dev) or message us on [Discord](https://go.zeroentropy.dev/discord) or [Slack](https://go.zeroentropy.dev/slack)! type: object required: - results - total_bytes - total_tokens - actual_latency_mode - e2e_latency - inference_latency title: RerankResponse HTTPValidationError: properties: detail: items: $ref: '#/components/schemas/ValidationError' type: array title: Detail type: object title: HTTPValidationError RerankResult: properties: index: type: integer title: Index description: >- The index of this document, relative to the original document array passed into the request. relevance_score: type: number title: Relevance Score description: >- The relevance score between this document and the query. This number will range between 0.0 and 1.0. This score is dependent on only the query and the scored document; other documents do not affect this score. This value is intended to be deterministic, but it may vary slightly due to floating point error. type: object required: - index - relevance_score title: RerankResult ValidationError: properties: loc: items: anyOf: - type: string - type: integer type: array title: Location msg: type: string title: Message type: type: string title: Error Type type: object required: - loc - msg - type title: ValidationError securitySchemes: HTTPBearer: type: http description: >- The `Authorization` header must be provided in the format `Bearer `. You can get your API Key at the [Dashboard](https://dashboard.zeroentropy.dev/)! scheme: bearer ````