Rerank documents by relevance
curl --request POST \
--url https://api.impossibl.com/v1/rerank \
--header 'Authorization: Bearer <token>' \
--header 'Content-Type: application/json' \
--data '
{
"model": "qwen/qwen3-reranker-8b",
"query": "<string>",
"documents": [
"<string>"
],
"top_n": 2,
"return_documents": true,
"task": "<string>"
}
'import requests
url = "https://api.impossibl.com/v1/rerank"
payload = {
"model": "qwen/qwen3-reranker-8b",
"query": "<string>",
"documents": ["<string>"],
"top_n": 2,
"return_documents": True,
"task": "<string>"
}
headers = {
"Authorization": "Bearer <token>",
"Content-Type": "application/json"
}
response = requests.post(url, json=payload, headers=headers)
print(response.text)const options = {
method: 'POST',
headers: {Authorization: 'Bearer <token>', 'Content-Type': 'application/json'},
body: JSON.stringify({
model: 'qwen/qwen3-reranker-8b',
query: '<string>',
documents: ['<string>'],
top_n: 2,
return_documents: true,
task: '<string>'
})
};
fetch('https://api.impossibl.com/v1/rerank', options)
.then(res => res.json())
.then(res => console.log(res))
.catch(err => console.error(err));<?php
$curl = curl_init();
curl_setopt_array($curl, [
CURLOPT_URL => "https://api.impossibl.com/v1/rerank",
CURLOPT_RETURNTRANSFER => true,
CURLOPT_ENCODING => "",
CURLOPT_MAXREDIRS => 10,
CURLOPT_TIMEOUT => 30,
CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
CURLOPT_CUSTOMREQUEST => "POST",
CURLOPT_POSTFIELDS => json_encode([
'model' => 'qwen/qwen3-reranker-8b',
'query' => '<string>',
'documents' => [
'<string>'
],
'top_n' => 2,
'return_documents' => true,
'task' => '<string>'
]),
CURLOPT_HTTPHEADER => [
"Authorization: Bearer <token>",
"Content-Type: application/json"
],
]);
$response = curl_exec($curl);
$err = curl_error($curl);
curl_close($curl);
if ($err) {
echo "cURL Error #:" . $err;
} else {
echo $response;
}package main
import (
"fmt"
"strings"
"net/http"
"io"
)
func main() {
url := "https://api.impossibl.com/v1/rerank"
payload := strings.NewReader("{\n \"model\": \"qwen/qwen3-reranker-8b\",\n \"query\": \"<string>\",\n \"documents\": [\n \"<string>\"\n ],\n \"top_n\": 2,\n \"return_documents\": true,\n \"task\": \"<string>\"\n}")
req, _ := http.NewRequest("POST", url, payload)
req.Header.Add("Authorization", "Bearer <token>")
req.Header.Add("Content-Type", "application/json")
res, _ := http.DefaultClient.Do(req)
defer res.Body.Close()
body, _ := io.ReadAll(res.Body)
fmt.Println(string(body))
}HttpResponse<String> response = Unirest.post("https://api.impossibl.com/v1/rerank")
.header("Authorization", "Bearer <token>")
.header("Content-Type", "application/json")
.body("{\n \"model\": \"qwen/qwen3-reranker-8b\",\n \"query\": \"<string>\",\n \"documents\": [\n \"<string>\"\n ],\n \"top_n\": 2,\n \"return_documents\": true,\n \"task\": \"<string>\"\n}")
.asString();require 'uri'
require 'net/http'
url = URI("https://api.impossibl.com/v1/rerank")
http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true
request = Net::HTTP::Post.new(url)
request["Authorization"] = 'Bearer <token>'
request["Content-Type"] = 'application/json'
request.body = "{\n \"model\": \"qwen/qwen3-reranker-8b\",\n \"query\": \"<string>\",\n \"documents\": [\n \"<string>\"\n ],\n \"top_n\": 2,\n \"return_documents\": true,\n \"task\": \"<string>\"\n}"
response = http.request(request)
puts response.read_body{
"object": "list",
"model": "qwen/qwen3-reranker-8b",
"data": [
{
"index": 1,
"relevance_score": 123,
"document": "<string>"
}
],
"usage": {
"prompt_tokens": 2,
"total_tokens": 2
}
}{
"error": {
"message": "`model` and `messages` are required",
"type": "invalid_request_error"
}
}{
"error": {
"message": "Invalid API key",
"type": "authentication_error"
}
}{
"error": {
"message": "Insufficient credits. Top up to continue.",
"type": "insufficient_quota"
}
}{
"error": {
"message": "Unknown model: foo/bar",
"type": "invalid_request_error"
}
}{
"error": {
"message": "permission-denied: ...",
"type": "upstream_error"
}
}{
"error": {
"message": "Provider not configured: missing OPENAI_API_KEY",
"type": "provider_not_configured"
}
}API Reference
Rerank documents by relevance
Rank document strings against a query. Requires a model whose output_modality is rerank. Billed on provider-reported input tokens only; non-streaming. Input is capped at 1,200,000 characters across query/document pairs, including the repeated query and optional task.
POST
/
v1
/
rerank
Rerank documents by relevance
curl --request POST \
--url https://api.impossibl.com/v1/rerank \
--header 'Authorization: Bearer <token>' \
--header 'Content-Type: application/json' \
--data '
{
"model": "qwen/qwen3-reranker-8b",
"query": "<string>",
"documents": [
"<string>"
],
"top_n": 2,
"return_documents": true,
"task": "<string>"
}
'import requests
url = "https://api.impossibl.com/v1/rerank"
payload = {
"model": "qwen/qwen3-reranker-8b",
"query": "<string>",
"documents": ["<string>"],
"top_n": 2,
"return_documents": True,
"task": "<string>"
}
headers = {
"Authorization": "Bearer <token>",
"Content-Type": "application/json"
}
response = requests.post(url, json=payload, headers=headers)
print(response.text)const options = {
method: 'POST',
headers: {Authorization: 'Bearer <token>', 'Content-Type': 'application/json'},
body: JSON.stringify({
model: 'qwen/qwen3-reranker-8b',
query: '<string>',
documents: ['<string>'],
top_n: 2,
return_documents: true,
task: '<string>'
})
};
fetch('https://api.impossibl.com/v1/rerank', options)
.then(res => res.json())
.then(res => console.log(res))
.catch(err => console.error(err));<?php
$curl = curl_init();
curl_setopt_array($curl, [
CURLOPT_URL => "https://api.impossibl.com/v1/rerank",
CURLOPT_RETURNTRANSFER => true,
CURLOPT_ENCODING => "",
CURLOPT_MAXREDIRS => 10,
CURLOPT_TIMEOUT => 30,
CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
CURLOPT_CUSTOMREQUEST => "POST",
CURLOPT_POSTFIELDS => json_encode([
'model' => 'qwen/qwen3-reranker-8b',
'query' => '<string>',
'documents' => [
'<string>'
],
'top_n' => 2,
'return_documents' => true,
'task' => '<string>'
]),
CURLOPT_HTTPHEADER => [
"Authorization: Bearer <token>",
"Content-Type: application/json"
],
]);
$response = curl_exec($curl);
$err = curl_error($curl);
curl_close($curl);
if ($err) {
echo "cURL Error #:" . $err;
} else {
echo $response;
}package main
import (
"fmt"
"strings"
"net/http"
"io"
)
func main() {
url := "https://api.impossibl.com/v1/rerank"
payload := strings.NewReader("{\n \"model\": \"qwen/qwen3-reranker-8b\",\n \"query\": \"<string>\",\n \"documents\": [\n \"<string>\"\n ],\n \"top_n\": 2,\n \"return_documents\": true,\n \"task\": \"<string>\"\n}")
req, _ := http.NewRequest("POST", url, payload)
req.Header.Add("Authorization", "Bearer <token>")
req.Header.Add("Content-Type", "application/json")
res, _ := http.DefaultClient.Do(req)
defer res.Body.Close()
body, _ := io.ReadAll(res.Body)
fmt.Println(string(body))
}HttpResponse<String> response = Unirest.post("https://api.impossibl.com/v1/rerank")
.header("Authorization", "Bearer <token>")
.header("Content-Type", "application/json")
.body("{\n \"model\": \"qwen/qwen3-reranker-8b\",\n \"query\": \"<string>\",\n \"documents\": [\n \"<string>\"\n ],\n \"top_n\": 2,\n \"return_documents\": true,\n \"task\": \"<string>\"\n}")
.asString();require 'uri'
require 'net/http'
url = URI("https://api.impossibl.com/v1/rerank")
http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true
request = Net::HTTP::Post.new(url)
request["Authorization"] = 'Bearer <token>'
request["Content-Type"] = 'application/json'
request.body = "{\n \"model\": \"qwen/qwen3-reranker-8b\",\n \"query\": \"<string>\",\n \"documents\": [\n \"<string>\"\n ],\n \"top_n\": 2,\n \"return_documents\": true,\n \"task\": \"<string>\"\n}"
response = http.request(request)
puts response.read_body{
"object": "list",
"model": "qwen/qwen3-reranker-8b",
"data": [
{
"index": 1,
"relevance_score": 123,
"document": "<string>"
}
],
"usage": {
"prompt_tokens": 2,
"total_tokens": 2
}
}{
"error": {
"message": "`model` and `messages` are required",
"type": "invalid_request_error"
}
}{
"error": {
"message": "Invalid API key",
"type": "authentication_error"
}
}{
"error": {
"message": "Insufficient credits. Top up to continue.",
"type": "insufficient_quota"
}
}{
"error": {
"message": "Unknown model: foo/bar",
"type": "invalid_request_error"
}
}{
"error": {
"message": "permission-denied: ...",
"type": "upstream_error"
}
}{
"error": {
"message": "Provider not configured: missing OPENAI_API_KEY",
"type": "provider_not_configured"
}
}Authorizations
Gateway API key (imp-rt-...) from POST /v1/accounts or /v1/keys.
Body
application/json
Example:
"qwen/qwen3-reranker-8b"
Search query used to score each document.
Minimum string length:
1Required array length:
1 - 1000 elementsMinimum string length:
1Number of results, at most the document count; defaults to all documents.
Required range:
x >= 1Include original document text in each result.
Optional description of the ranking task.
Minimum string length:
1⌘I

