POST /v1/rerank to order search results by relevance before passing the best
documents to a language model. Send a query and document strings; the response
returns scores and the original document indices, highest score first.
Rerank documents
index refers to the document’s position in your request, starting at zero.
return_documents: false omits the document text. top_n limits the returned
results; when omitted, all documents are returned. An optional task string
describes the ranking task to the model.
Models and billing
Discover supported models withGET /v1/models: rerankers have
output_modality: "rerank" and endpoints: ["/v1/rerank"]. Qwen3 Reranker 8B is
served by Fireworks at $0.20 per million input tokens. The provider’s reported
usage.prompt_tokens determines the charge, including the query/document pairs
it evaluates. There are no generated output tokens. Results and charges appear
in the same request log and usage ledger as other API calls.
Limits
Send 1–1,000 nonempty document strings and a nonempty query. The combined input is capped at 1,200,000 characters, counting the query and optional task once for each document. Each query/document pair must also fit the model’s context window.top_n must be an integer between 1 and the number of documents.
Reranking is non-streaming and uses the gateway’s provider credentials. Requests
require an API key and sufficient credits. Sending this model to a chat or
embedding endpoint returns 400 with the correct /v1/rerank destination.
