Merge pull request #599 from Routstr/fix/cost-calculation-breakdown

Fix input/output cost breakdown calculation
This commit is contained in:
9qeklajc
2026-07-12 13:25:08 +02:00
committed by GitHub
2 changed files with 191 additions and 40 deletions
+87 -40
View File
@@ -157,11 +157,16 @@ async def calculate_cost(
},
)
try:
cost_details = usage_data.get("cost_details", {})
if not isinstance(cost_details, dict):
cost_details = {}
input_usd = _coerce_usd(
usage_data.get("cost_details", {}).get("input_cost", 0)
cost_details.get("input_cost")
or cost_details.get("upstream_inference_prompt_cost")
)
output_usd = _coerce_usd(
usage_data.get("cost_details", {}).get("output_cost", 0)
cost_details.get("output_cost")
or cost_details.get("upstream_inference_completions_cost")
)
return _calculate_from_usd_cost(
usd_cost,
@@ -281,54 +286,92 @@ def _resolve_usd_cost(usage_data: dict, response_data: dict) -> float:
def _get_pricing_rates(
response_data: dict,
) -> tuple[float, float, float, float] | None:
"""Get model-based pricing rates or None if using fixed pricing.
"""Get configured rates, falling back to LiteLLM's model cost map.
Returns: (input_rate, output_rate, cache_read_rate, cache_write_rate)
Returns: (input_rate, output_rate, cache_read_rate, cache_write_rate).
``None`` means configured fixed pricing should be used by the caller.
"""
if settings.fixed_pricing:
if settings.fixed_pricing and (
settings.fixed_per_1k_input_tokens
or settings.fixed_per_1k_output_tokens
):
return None
from ..proxy import get_model_instance
from .models import litellm_cost_entry
response_model = response_data.get("model", "")
model_obj = get_model_instance(response_model)
if not model_obj:
logger.error("Invalid model in response", extra={"response_model": response_model})
raise ValueError(f"Invalid model: {response_model}")
if model_obj and model_obj.sats_pricing:
try:
mspp = float(model_obj.sats_pricing.prompt)
mspc = float(model_obj.sats_pricing.completion)
mscr = float(model_obj.sats_pricing.input_cache_read or 0)
mscw = float(model_obj.sats_pricing.input_cache_write or 0)
if not model_obj.sats_pricing:
logger.error(
"Model pricing not defined",
extra={"model": response_model, "model_id": response_model},
mspp_1k = mspp * 1_000_000.0
mspc_1k = mspc * 1_000_000.0
mscr_1k = mscr * 1_000_000.0 if mscr > 0 else mspp_1k
mscw_1k = mscw * 1_000_000.0 if mscw > 0 else mspp_1k
source = "configured"
except Exception as e:
logger.error("Invalid pricing data", extra={"error": str(e)})
raise ValueError("Invalid pricing data") from e
else:
pricing_model = (
model_obj.forwarded_model_id if model_obj else None
) or response_model
pricing = litellm_cost_entry(pricing_model)
if pricing is None:
logger.error(
"Model pricing not found in configured models or LiteLLM",
extra={
"response_model": response_model,
"pricing_model": pricing_model,
},
)
raise ValueError(f"Pricing not found for model: {response_model}")
input_usd = _coerce_usd(pricing.get("input_cost_per_token"))
output_usd = _coerce_usd(pricing.get("output_cost_per_token"))
if input_usd <= 0 or output_usd <= 0:
raise ValueError(f"Incomplete LiteLLM pricing for model: {pricing_model}")
provider_fee = _resolve_provider_fee(response_model)
usd_per_sat = sats_usd_price()
mspp_1k = input_usd * provider_fee * 1_000_000.0 / usd_per_sat
mspc_1k = output_usd * provider_fee * 1_000_000.0 / usd_per_sat
cache_read_usd = _coerce_usd(
pricing.get("cache_read_input_token_cost")
)
raise ValueError("Model pricing not defined")
try:
mspp = float(model_obj.sats_pricing.prompt)
mspc = float(model_obj.sats_pricing.completion)
mscr = float(model_obj.sats_pricing.input_cache_read or 0)
mscw = float(model_obj.sats_pricing.input_cache_write or 0)
mspp_1k = mspp * 1_000_000.0
mspc_1k = mspc * 1_000_000.0
mscr_1k = mscr * 1_000_000.0 if mscr > 0 else mspp_1k
mscw_1k = mscw * 1_000_000.0 if mscw > 0 else mspp_1k
logger.info(
"Applied model-specific pricing",
extra={
"model": response_model,
"input_price_msats_per_1k": mspp_1k,
"output_price_msats_per_1k": mspc_1k,
"cache_read_price_msats_per_1k": mscr_1k,
"cache_write_price_msats_per_1k": mscw_1k,
},
cache_write_usd = _coerce_usd(
pricing.get("cache_creation_input_token_cost")
)
return mspp_1k, mspc_1k, mscr_1k, mscw_1k
except Exception as e:
logger.error("Invalid pricing data", extra={"error": str(e)})
raise ValueError("Invalid pricing data") from e
mscr_1k = (
cache_read_usd * provider_fee * 1_000_000.0 / usd_per_sat
if cache_read_usd > 0
else mspp_1k
)
mscw_1k = (
cache_write_usd * provider_fee * 1_000_000.0 / usd_per_sat
if cache_write_usd > 0
else mspp_1k
)
source = "litellm"
logger.info(
"Applied model-specific pricing",
extra={
"model": response_model,
"pricing_source": source,
"input_price_msats_per_1k": mspp_1k,
"output_price_msats_per_1k": mspc_1k,
"cache_read_price_msats_per_1k": mscr_1k,
"cache_write_price_msats_per_1k": mscw_1k,
},
)
return mspp_1k, mspc_1k, mscr_1k, mscw_1k
def _resolve_provider_fee(model_id: str) -> float:
@@ -367,8 +410,12 @@ def _calculate_from_usd_cost(
cost_in_msats = math.ceil(cost_in_sats * 1000)
if input_usd > 0 or output_usd > 0:
input_msats = int((input_usd * sats_per_usd) * 1000)
output_msats = int((output_usd * sats_per_usd) * 1000)
# The total is the authoritative billed amount. Allocating that integer
# total proportionally avoids losing sub-millisatoshi remainders when
# input and output components are each truncated independently.
component_usd = input_usd + output_usd
input_msats = math.floor(cost_in_msats * input_usd / component_usd)
output_msats = cost_in_msats - input_msats
else:
effective_input_tokens = (
input_tokens + cache_read_tokens + cache_creation_tokens
+104
View File
@@ -465,9 +465,113 @@ async def test_cache_read_only_usd_cost_response_is_billed(
assert result.cache_read_input_tokens == 1000
@pytest.mark.asyncio
@pytest.mark.parametrize(
("total_cost", "input_cost", "output_cost", "expected_msats"),
[
(0.000471, 0.00023451, 0.00023649, 9420),
(0.00000004, 0.00000002, 0.00000002, 1),
],
)
async def test_small_usd_cost_components_sum_to_rounded_total(
total_cost: float,
input_cost: float,
output_cost: float,
expected_msats: int,
) -> None:
"""Small USD component costs must retain every billed millisatoshi."""
response = {
"model": "gpt-4",
"usage": {
"prompt_tokens": 1,
"completion_tokens": 1,
"cost_details": {
"total_cost": total_cost,
"input_cost": input_cost,
"output_cost": output_cost,
},
},
}
result = await calculate_cost(response, max_cost=100000)
assert isinstance(result, CostData)
assert result.total_msats == expected_msats
assert result.input_msats + result.output_msats == result.total_msats
@pytest.mark.asyncio
async def test_openrouter_upstream_inference_cost_components_are_used() -> None:
"""OpenRouter component aliases must determine the input/output split."""
response = {
"model": "gpt-4",
"usage": {
"prompt_tokens": 375,
"completion_tokens": 158,
"total_tokens": 533,
"cost": 0.00022354,
"is_byok": False,
"prompt_tokens_details": {
"cached_tokens": 286,
"cache_write_tokens": 0,
},
"cost_details": {
"upstream_inference_cost": 0.00022354,
"upstream_inference_prompt_cost": 0.00004974,
"upstream_inference_completions_cost": 0.0001738,
},
"completion_tokens_details": {"reasoning_tokens": 17},
},
}
result = await calculate_cost(response, max_cost=100000)
assert isinstance(result, CostData)
assert result.input_msats == 994
assert result.output_msats == 3477
assert result.input_msats + result.output_msats == result.total_msats == 4471
# ============================================================================
# Test 13: Missing Usage Block
# ============================================================================
@pytest.mark.asyncio
async def test_missing_upstream_cost_uses_litellm_model_pricing(
monkeypatch: pytest.MonkeyPatch,
) -> None:
"""Token usage without an upstream cost is priced from LiteLLM."""
monkeypatch.setattr(settings, "fixed_pricing", True)
monkeypatch.setattr(settings, "fixed_per_1k_input_tokens", 0)
monkeypatch.setattr(settings, "fixed_per_1k_output_tokens", 0)
monkeypatch.setattr(
"routstr.payment.models.litellm_cost_entry",
lambda model: {
"input_cost_per_token": 0.000001,
"output_cost_per_token": 0.000002,
},
)
response = {
"model": "priced-by-litellm",
"usage": {
"prompt_tokens": 90,
"completion_tokens": 80,
"total_tokens": 170,
"prompt_tokens_details": {"cached_tokens": 0},
"completion_tokens_details": {"reasoning_tokens": 74},
"prompt_cache_hit_tokens": 0,
"prompt_cache_miss_tokens": 90,
},
}
result = await calculate_cost(response, max_cost=10000)
assert isinstance(result, CostData)
assert not isinstance(result, MaxCostData)
assert result.input_msats == 1800
assert result.output_msats == 3200
assert result.input_msats + result.output_msats == result.total_msats == 5000
@pytest.mark.asyncio
async def test_missing_usage_block(mock_fixed_pricing: None) -> None:
"""When usage is missing, return MaxCostData with zero tokens."""