curl --request GET \
--url https://openrouter.ai/api/v1/datasets/session-cost \
--header 'Authorization: Bearer <token>'import requests
url = "https://openrouter.ai/api/v1/datasets/session-cost"
headers = {"Authorization": "Bearer <token>"}
response = requests.get(url, headers=headers)
print(response.text)const options = {method: 'GET', headers: {Authorization: 'Bearer <token>'}};
fetch('https://openrouter.ai/api/v1/datasets/session-cost', 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://openrouter.ai/api/v1/datasets/session-cost",
CURLOPT_RETURNTRANSFER => true,
CURLOPT_ENCODING => "",
CURLOPT_MAXREDIRS => 10,
CURLOPT_TIMEOUT => 30,
CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
CURLOPT_CUSTOMREQUEST => "GET",
CURLOPT_HTTPHEADER => [
"Authorization: Bearer <token>"
],
]);
$response = curl_exec($curl);
$err = curl_error($curl);
curl_close($curl);
if ($err) {
echo "cURL Error #:" . $err;
} else {
echo $response;
}package main
import (
"fmt"
"net/http"
"io"
)
func main() {
url := "https://openrouter.ai/api/v1/datasets/session-cost"
req, _ := http.NewRequest("GET", url, nil)
req.Header.Add("Authorization", "Bearer <token>")
res, _ := http.DefaultClient.Do(req)
defer res.Body.Close()
body, _ := io.ReadAll(res.Body)
fmt.Println(string(body))
}HttpResponse<String> response = Unirest.get("https://openrouter.ai/api/v1/datasets/session-cost")
.header("Authorization", "Bearer <token>")
.asString();require 'uri'
require 'net/http'
url = URI("https://openrouter.ai/api/v1/datasets/session-cost")
http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true
request = Net::HTTP::Get.new(url)
request["Authorization"] = 'Bearer <token>'
response = http.request(request)
puts response.read_body{
"data": [
{
"app_name": "Hermes Agent",
"app_slug": "hermes-agent",
"median_session_cost_usd": 1.74,
"model_permaslug": "anthropic/claude-4.8-opus",
"turn_range": "10-49-turns"
}
],
"meta": {
"as_of": "2026-05-12T02:00:00.000Z",
"version": "v1",
"window_days": 30,
"window_end_date": "2026-05-11"
}
}{
"error": {
"code": 400,
"message": "Invalid request parameters"
}
}{
"error": {
"code": 401,
"message": "Missing Authentication header"
}
}{
"error": {
"code": 429,
"message": "Rate limit exceeded"
}
}{
"error": {
"code": 500,
"message": "Internal Server Error"
}
}Cost per session by harness and model
Returns weekly refreshed, aggregated cost-per-session cells for the published harnesses. Sessions are never pooled across apps. Medians are of per-session USD spend, and privacy-preserving aggregation never exposes clerk_user_id values or per-session rows.
Filter by app_slug, model, or turn_range. Filtering by model alone works across apps
for harness-vs-harness comparison at a fixed model. Results refresh weekly and include the source snapshot
window in meta.
Licensed under CC BY 4.0: reuse and republish with attribution to OpenRouter.
curl --request GET \
--url https://openrouter.ai/api/v1/datasets/session-cost \
--header 'Authorization: Bearer <token>'import requests
url = "https://openrouter.ai/api/v1/datasets/session-cost"
headers = {"Authorization": "Bearer <token>"}
response = requests.get(url, headers=headers)
print(response.text)const options = {method: 'GET', headers: {Authorization: 'Bearer <token>'}};
fetch('https://openrouter.ai/api/v1/datasets/session-cost', 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://openrouter.ai/api/v1/datasets/session-cost",
CURLOPT_RETURNTRANSFER => true,
CURLOPT_ENCODING => "",
CURLOPT_MAXREDIRS => 10,
CURLOPT_TIMEOUT => 30,
CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
CURLOPT_CUSTOMREQUEST => "GET",
CURLOPT_HTTPHEADER => [
"Authorization: Bearer <token>"
],
]);
$response = curl_exec($curl);
$err = curl_error($curl);
curl_close($curl);
if ($err) {
echo "cURL Error #:" . $err;
} else {
echo $response;
}package main
import (
"fmt"
"net/http"
"io"
)
func main() {
url := "https://openrouter.ai/api/v1/datasets/session-cost"
req, _ := http.NewRequest("GET", url, nil)
req.Header.Add("Authorization", "Bearer <token>")
res, _ := http.DefaultClient.Do(req)
defer res.Body.Close()
body, _ := io.ReadAll(res.Body)
fmt.Println(string(body))
}HttpResponse<String> response = Unirest.get("https://openrouter.ai/api/v1/datasets/session-cost")
.header("Authorization", "Bearer <token>")
.asString();require 'uri'
require 'net/http'
url = URI("https://openrouter.ai/api/v1/datasets/session-cost")
http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true
request = Net::HTTP::Get.new(url)
request["Authorization"] = 'Bearer <token>'
response = http.request(request)
puts response.read_body{
"data": [
{
"app_name": "Hermes Agent",
"app_slug": "hermes-agent",
"median_session_cost_usd": 1.74,
"model_permaslug": "anthropic/claude-4.8-opus",
"turn_range": "10-49-turns"
}
],
"meta": {
"as_of": "2026-05-12T02:00:00.000Z",
"version": "v1",
"window_days": 30,
"window_end_date": "2026-05-11"
}
}{
"error": {
"code": 400,
"message": "Invalid request parameters"
}
}{
"error": {
"code": 401,
"message": "Missing Authentication header"
}
}{
"error": {
"code": 429,
"message": "Rate limit exceeded"
}
}{
"error": {
"code": 500,
"message": "Internal Server Error"
}
}Authorizations
API key as bearer token in Authorization header
Query Parameters
Filter to one published harness slug.
"hermes-agent"
Exact model permaslug filter. Works across all harness apps.
"anthropic/claude-4.8-opus"
Filter by the inclusive number of turns in a session.
1-turn, 2-9-turns, 10-49-turns, 50-plus-turns "10-49-turns"
Maximum number of cells to return (1-500). Defaults to 100.
1 <= x <= 500100
Number of sorted cells to skip (0-5000). Defaults to 0.
0 <= x <= 50000