fix(spend): price compression/caching savings from deployment rates

This commit is contained in:
Gyanu 2026-08-23 08:51:14 +05:30
parent 947dbbf029
commit cb6acd7258
2 changed files with 393 additions and 9 deletions

View file

@ -9,7 +9,13 @@ have been aggregated across models.
"""
from collections.abc import Callable, Mapping
from typing import TYPE_CHECKING, Final, NamedTuple
from typing import (
TYPE_CHECKING,
Final,
NamedTuple,
TypeGuard, # noqa: TID251 # TypeGuard narrows optional ModelInfo after the input-rate check
cast, # noqa: TID251 # model_cost dicts are ModelInfo-shaped after the input-rate check
)
import litellm
from litellm._logging import verbose_proxy_logger
@ -110,6 +116,142 @@ def _effective_model_info(router: "Router | None", deployment_id: str | None, mo
return None
def _has_input_price(
info: ModelInfo | None,
) -> TypeGuard[ModelInfo]: # guard-ok: ModelInfo | None is priced iff input_cost_per_token is present
"""True when ``info`` carries a real input rate, including an explicit ``0``.
Router registers two keys per deployment: the deployment id keeps custom prices,
and the shared ``{provider}/{model}`` key has every cost field stripped so two
deployments of the same backend cannot clobber each other. ``get_model_info``
prefers that shared key, so a custom model absent from the built-in map resolves
to a dict that looks like a hit and then prices at ``0.0``. Treating a missing
rate as "no info" lets the caller keep looking at the deployment id.
"""
return info is not None and info.get("input_cost_per_token") is not None
def _savings_rate_fingerprint(info: ModelInfo) -> tuple[float, float, float]:
"""The effective rates savings uses, after applying cache-price defaults."""
return _input_cache_read_and_write_cost(info)
def _input_rate_fingerprint(info: ModelInfo) -> float:
"""The input rate only. Compression does not care about cache prices."""
input_cost, _, _ = _savings_rate_fingerprint(info)
return input_cost
def _cost_map_deployment_info(deployment_id: str | None) -> ModelInfo | None:
"""Pricing registered under a deployment id, without needing a live Router.
Daily spend writes pass ``model_id`` but look the router up lazily. When that
lookup returns ``None``, falling through to the stripped shared key reports
``$0.00`` savings even though the deployment's rate is already in ``model_cost``.
"""
if not deployment_id:
return None
info = litellm.model_cost.get(deployment_id)
if isinstance(info, dict) and info.get("input_cost_per_token") is not None:
return cast(
ModelInfo, info
) # cast-ok: model_cost dict already checked for input_cost_per_token; same shape router uses
return None
def _deployment_matches_logged_model(
dep_model: str,
dep_provider: object,
public_name: object,
identity: _ModelIdentity | None,
logged_model: str,
) -> bool:
"""True when this router row is the deployment a spend log row is talking about."""
if logged_model and logged_model == public_name:
return True
dep_identity = _resolve_model(dep_model, dep_provider if isinstance(dep_provider, str) else None)
if identity is not None and dep_identity is not None:
return identity == dep_identity
return bool(logged_model) and logged_model == dep_model
def _matching_priced_deployments(
router: "Router | None",
identity: _ModelIdentity | None,
logged_model: str,
) -> list[ModelInfo]:
"""Priced router rows that could be this spend log, or empty if we cannot tell."""
if router is None:
return []
try:
deployments = router.get_model_list() or []
except Exception as e: # noqa: BLE001 # a dashboard metric must not fail the spend write
verbose_proxy_logger.debug("savings: cannot list deployments (%s)", e)
return []
priced: list[ModelInfo] = []
seen_ids: set[str] = set()
for dep in deployments:
if not isinstance(dep, dict):
continue
dep_id = (dep.get("model_info") or {}).get("id")
if not isinstance(dep_id, str) or dep_id in seen_ids:
continue
params = dep.get("litellm_params") or {}
if not _deployment_matches_logged_model(
dep_model=str(params.get("model") or ""),
dep_provider=params.get("custom_llm_provider"),
public_name=dep.get("model_name"),
identity=identity,
logged_model=logged_model,
):
continue
seen_ids.add(dep_id)
info = _cost_map_deployment_info(dep_id) or _effective_model_info(router, dep_id, logged_model)
if _has_input_price(info):
priced.append(info)
return priced
def _unique_by_rate(
priced: list[ModelInfo],
rate_key: Callable[[ModelInfo], object],
) -> ModelInfo | None:
if not priced:
return None
fingerprints = {rate_key(info) for info in priced}
return priced[0] if len(fingerprints) == 1 else None
def _pricing_for_savings(
router: "Router | None",
model_id: str | None,
identity: _ModelIdentity | None,
model: str | None,
rate_key: Callable[[ModelInfo], object] = _savings_rate_fingerprint,
) -> ModelInfo | None:
"""Deployment rate first, public rate only when it actually has a price."""
logged = model or ""
candidates: list[ModelInfo | None] = [
_cost_map_deployment_info(model_id),
_effective_model_info(router, model_id, logged),
]
if not model_id:
priced = _matching_priced_deployments(router, identity, logged)
if priced:
unique = _unique_by_rate(priced, rate_key)
if unique is None:
# Matching deployments disagree. The public list price is not a
# substitute — it can match none of them.
return None
candidates.append(unique)
candidates.append(_model_info(identity) if identity else None)
for candidate in candidates:
if _has_input_price(candidate):
return candidate
return None
def _model_info(model: _ModelIdentity) -> ModelInfo | None:
"""The public rates for ``model``, or ``None`` when it has none."""
try:
@ -588,15 +730,23 @@ def compute_savings_spend(
nothing and recompute, mirroring ``_recorded_token_cost``.
"""
# Deployment rates when the request came through one, public rates otherwise --
# `_effective_model_info` merges a deployment's configured prices over the built-in
# map, so a negotiated price is not silently replaced by the list rate.
# `_pricing_for_savings` prefers the deployment-id cost-map entry (even with no
# live Router) so a custom model whose shared `{provider}/{model}` key had its
# prices stripped is not silently billed at $0.
# Without model_id, compression can still use a unique input rate when cache
# rates differ; prompt-caching needs the full fingerprint or it would pick
# the first deployment's cache price.
router_instance: Router | None = llm_router() if llm_router else None
identity: Final = _resolve_model(model, custom_llm_provider)
pricing: Final = _effective_model_info(router_instance, model_id, model or "") or (
_model_info(identity) if identity else None
cache_pricing: Final = _pricing_for_savings(router_instance, model_id, identity, model)
compression_pricing: Final = (
cache_pricing
if model_id
else _pricing_for_savings(router_instance, model_id, identity, model, rate_key=_input_rate_fingerprint)
)
input_cost, cache_read_cost, cache_write_cost = _input_cache_read_and_write_cost(pricing)
compression: Final = max(compression_saved_tokens, 0) * input_cost
compression_input, _, _ = _input_cache_read_and_write_cost(compression_pricing)
input_cost, cache_read_cost, cache_write_cost = _input_cache_read_and_write_cost(cache_pricing)
compression: Final = max(compression_saved_tokens, 0) * compression_input
cache_read_input_tokens: Final = extract_cache_read_tokens(usage_object)
cache_creation_input_tokens: Final = extract_cache_creation_tokens(usage_object)
read_discount: Final = max(cache_read_input_tokens, 0) * max(input_cost - cache_read_cost, 0.0)

View file

@ -1,5 +1,3 @@
import pytest
import litellm
@ -1010,6 +1008,242 @@ def test_a_recorded_baseline_deployment_prices_at_its_configured_rate():
assert with_deployment_rate.autorouter > at_public_rate.autorouter
def _custom_unmapped_router():
"""A self-hosted model that is not in the built-in cost map."""
return Router(
model_list=[
{
"model_name": "muse-glimmer-30b",
"litellm_params": {
"model": "muse-glimmer-30b",
"custom_llm_provider": "openai",
"api_base": "https://example.invalid/v1",
"api_key": "sk-test",
"input_cost_per_token": 3.5e-07,
"output_cost_per_token": 1.5e-06,
"cache_read_input_token_cost": 3.5e-08,
},
},
]
)
def test_custom_unmapped_model_compression_savings_use_deployment_id_without_router():
"""A custom model's rate lives on the deployment-id cost-map key.
The spend writer always has ``model_id``; it does not always have a live Router.
Looking the rate up only through ``get_model_info`` hits the stripped shared
backend key and reports $0.00 next to a non-zero token count.
"""
router = _custom_unmapped_router()
deployment_id = router.get_model_list(model_name="muse-glimmer-30b")[0]["model_info"]["id"]
result = compute_savings_spend(
model="muse-glimmer-30b",
custom_llm_provider="openai",
compression_saved_tokens=2642007,
model_id=deployment_id,
)
assert result.compression == pytest.approx(2642007 * 3.5e-07)
assert result.compression > 0
def test_custom_unmapped_model_compression_savings_without_model_id_use_unique_deployment():
"""A single custom deployment can still be priced when the log omitted model_id."""
router = _custom_unmapped_router()
result = compute_savings_spend(
model="muse-glimmer-30b",
custom_llm_provider="openai",
compression_saved_tokens=100000,
llm_router=lambda: router,
)
assert result.compression == pytest.approx(100000 * 3.5e-07)
def test_custom_unmapped_model_prompt_caching_savings_use_deployment_rate():
router = _custom_unmapped_router()
deployment_id = router.get_model_list(model_name="muse-glimmer-30b")[0]["model_info"]["id"]
result = compute_savings_spend(
model="muse-glimmer-30b",
custom_llm_provider="openai",
compression_saved_tokens=0,
usage_object={"cache_read_input_tokens": 500000},
model_id=deployment_id,
)
assert result.prompt_caching == pytest.approx(500000 * (3.5e-07 - 3.5e-08))
assert result.prompt_caching > 0
def test_two_custom_deployments_at_different_rates_need_model_id():
"""The public model_name is shared; without model_id the rate cannot be guessed."""
router = Router(
model_list=[
{
"model_name": "deepseek-v4-pro",
"litellm_params": {
"model": "openrouter/deepseek/deepseek-v4-pro",
"api_key": "sk-openrouter",
"input_cost_per_token": 4.225e-07,
"output_cost_per_token": 8.45e-07,
"cache_read_input_token_cost": 3.5e-08,
},
},
{
"model_name": "deepseek-v4-pro",
"litellm_params": {
"model": "openai/deepseek-v4-pro",
"custom_llm_provider": "openai",
"api_base": "https://example.invalid/zen",
"api_key": "sk-zen",
"input_cost_per_token": 1.74e-06,
"output_cost_per_token": 3.84e-06,
"cache_read_input_token_cost": 1.74e-07,
},
},
]
)
openrouter_id = router.get_model_list(model_name="deepseek-v4-pro")[0]["model_info"]["id"]
without_id = compute_savings_spend(
model="deepseek-v4-pro",
custom_llm_provider="openai",
compression_saved_tokens=100000,
llm_router=lambda: router,
)
with_id = compute_savings_spend(
model="deepseek/deepseek-v4-pro",
custom_llm_provider="openrouter",
compression_saved_tokens=100000,
model_id=openrouter_id,
)
assert without_id.compression == 0.0
assert with_id.compression == pytest.approx(100000 * 4.225e-07)
def test_same_input_rate_different_cache_rates_still_price_compression():
"""Compression only needs the input rate; prompt-caching still needs model_id.
Prompt-caching savings are ``tokens * (input - cache_read)``. Two deployments
at the same input price but different cache-read prices cannot share a cache
rate, but compression can still be priced from the unique input rate.
"""
router = Router(
model_list=[
{
"model_name": "muse-glimmer-30b",
"litellm_params": {
"model": "muse-glimmer-30b",
"custom_llm_provider": "openai",
"api_base": "https://example.invalid/v1",
"api_key": "sk-a",
"input_cost_per_token": 3.5e-07,
"output_cost_per_token": 1.5e-06,
"cache_read_input_token_cost": 3.5e-08,
},
},
{
"model_name": "muse-glimmer-30b",
"litellm_params": {
"model": "muse-glimmer-30b",
"custom_llm_provider": "openai",
"api_base": "https://example.invalid/v2",
"api_key": "sk-b",
"input_cost_per_token": 3.5e-07,
"output_cost_per_token": 1.5e-06,
"cache_read_input_token_cost": 1.0e-07,
},
},
]
)
without_id = compute_savings_spend(
model="muse-glimmer-30b",
custom_llm_provider="openai",
compression_saved_tokens=100000,
usage_object={"cache_read_input_tokens": 500000},
llm_router=lambda: router,
)
assert without_id.compression == pytest.approx(100000 * 3.5e-07)
assert without_id.prompt_caching == 0.0
def test_omitted_cache_rate_matches_explicit_mirror_of_input():
"""A missing cache price is the same effective rate as cache_read == input."""
router = Router(
model_list=[
{
"model_name": "muse-glimmer-30b",
"litellm_params": {
"model": "muse-glimmer-30b",
"custom_llm_provider": "openai",
"api_base": "https://example.invalid/v1",
"api_key": "sk-a",
"input_cost_per_token": 3.5e-07,
"output_cost_per_token": 1.5e-06,
},
},
{
"model_name": "muse-glimmer-30b",
"litellm_params": {
"model": "muse-glimmer-30b",
"custom_llm_provider": "openai",
"api_base": "https://example.invalid/v2",
"api_key": "sk-b",
"input_cost_per_token": 3.5e-07,
"output_cost_per_token": 1.5e-06,
"cache_read_input_token_cost": 3.5e-07,
"cache_creation_input_token_cost": 3.5e-07,
},
},
]
)
result = compute_savings_spend(
model="muse-glimmer-30b",
custom_llm_provider="openai",
compression_saved_tokens=100000,
llm_router=lambda: router,
)
assert result.compression == pytest.approx(100000 * 3.5e-07)
def test_ambiguous_cache_rates_do_not_fall_back_to_public_prompt_caching():
"""Disagreeing deployment cache rates must not be replaced by the public map."""
public_input, public_cache_read = _anthropic_costs("claude-sonnet-5")
router = Router(
model_list=[
{
"model_name": "claude-sonnet-5",
"litellm_params": {
"model": "claude-sonnet-5",
"custom_llm_provider": "anthropic",
"api_key": "sk-a",
"input_cost_per_token": public_input,
"cache_read_input_token_cost": 1.0e-08,
},
},
{
"model_name": "claude-sonnet-5",
"litellm_params": {
"model": "claude-sonnet-5",
"custom_llm_provider": "anthropic",
"api_key": "sk-b",
"input_cost_per_token": public_input,
"cache_read_input_token_cost": 5.0e-08,
},
},
]
)
result = compute_savings_spend(
model="claude-sonnet-5",
custom_llm_provider="anthropic",
compression_saved_tokens=100000,
usage_object={"cache_read_input_tokens": 500000},
llm_router=lambda: router,
)
public_prompt_caching = 500000 * max(public_input - public_cache_read, 0.0)
assert result.compression == pytest.approx(100000 * public_input)
assert result.prompt_caching == 0.0
assert public_prompt_caching != 0.0
def _routed_decision() -> dict:
return {"savings_baseline_model": "anthropic/claude-opus-5", "conversation_continuing": True}