Files
crewAI/lib/crewai/tests/test_flow_usage_metrics.py
Lucas Gomide 887adafd2c fix: aggregate token usage across all LLM calls (#6122)
* feat: aggregate LLM token usage at the flow level

Introduces `flow.usage_metrics`, a snapshot of every LLMCallCompletedEvent
emitted under the flow's `current_flow_id` for the duration of one kickoff
(or resume) call. Aggregation happens on the singleton event bus so it
covers crews, direct `LLM.call`s, and nested listener calls — solving the
mismatch where the SDK reported only the last crew's usage while the
Enterprise UI showed the correct full total.

Co-authored-by: Cursor <cursoragent@cursor.com>

* refactor: centralize provider key normalization in UsageMetrics

Add UsageMetrics.from_provider_dict to normalize raw LLM usage dicts
across providers (LiteLLM, native Anthropic, native Gemini, OpenAI
nested cached). BaseLLM._track_token_usage_internal and the flow-level
aggregator now share this single source of truth, so `flow.usage_metrics`
agrees with per-LLM totals on every provider — including the native
Anthropic path that emits `input_tokens`/`output_tokens` instead of
`prompt_tokens`/`completion_tokens`.

* fix: flush event bus before reading aggregated usage_metrics

`crewai_event_bus.emit` dispatches LLMCallCompletedEvent handlers on a
ThreadPoolExecutor (fire-and-forget), so a flow whose last LLM call
completes right before kickoff_async/resume_async returns can detach
the usage listener while that handler is still queued, leaving its
tokens off `flow.usage_metrics`. Match `Crew.kickoff()` and call
`crewai_event_bus.flush()` in both finally blocks so every handler
drains before the listener is detached.

---------

Co-authored-by: Cursor <cursoragent@cursor.com>
2026-06-12 12:55:22 -04:00

512 lines
18 KiB
Python

"""Tests for flow-level token usage aggregation
``flow.usage_metrics`` listens to ``LLMCallCompletedEvent`` for the duration
of ``kickoff_async`` so it covers every LLM call inside the flow — crew-led,
tool-led, AND bare ``LLM.call(...)`` from a flow method. We exercise the
aggregator end-to-end through the real event bus with fabricated events and
explicit contextvar control; no live LLM provider is required.
"""
from __future__ import annotations
import contextvars
import os
import tempfile
from typing import Any, Callable
from uuid import uuid4
import pytest
from crewai.events.event_bus import crewai_event_bus
from crewai.events.types.llm_events import LLMCallCompletedEvent, LLMCallType
from crewai.flow.async_feedback.types import PendingFeedbackContext
from crewai.flow.flow import Flow, listen, start
from crewai.flow.flow_context import current_flow_id
from crewai.flow.persistence.sqlite import SQLiteFlowPersistence
from crewai.flow.runtime import _usage_dict_to_metrics
from crewai.types.usage_metrics import UsageMetrics
def _emit_llm_call(
*,
flow_id: str | None,
prompt_tokens: int = 0,
completion_tokens: int = 0,
cached_prompt_tokens: int = 0,
reasoning_tokens: int = 0,
cache_creation_tokens: int = 0,
) -> None:
"""Emit one fake ``LLMCallCompletedEvent`` with ``current_flow_id`` pinned
to ``flow_id``.
Runs in a freshly-copied context so the value the bus snapshots at emit
time is exactly ``flow_id`` — independent of the calling thread's outer
context. Mirrors how the real ``LLM.call`` emits events at runtime.
"""
usage: dict[str, Any] = {
"prompt_tokens": prompt_tokens,
"completion_tokens": completion_tokens,
"total_tokens": prompt_tokens + completion_tokens,
}
for key, value in (
("cached_prompt_tokens", cached_prompt_tokens),
("reasoning_tokens", reasoning_tokens),
("cache_creation_tokens", cache_creation_tokens),
):
if value:
usage[key] = value
event = LLMCallCompletedEvent(
call_id=str(uuid4()),
model="gpt-4o-mini",
response="ok",
call_type=LLMCallType.LLM_CALL,
usage=usage,
)
ctx = contextvars.copy_context()
def _emit() -> None:
current_flow_id.set(flow_id)
future = crewai_event_bus.emit(object(), event)
if future is not None:
future.result(timeout=5.0)
ctx.run(_emit)
class _ScriptedFlow(Flow):
"""A Flow whose ``@start`` delegates to a per-instance ``_script`` closure.
Each test attaches a script with ``flow._script = lambda f: ...`` so we
don't redefine a Flow subclass for every scenario.
"""
@start()
def run(self) -> None:
script: Callable[[Flow], None] = getattr(self, "_script", lambda _f: None)
script(self)
def _run(script: Callable[[Flow], None] = lambda _f: None) -> Flow:
"""Build a ``_ScriptedFlow``, attach ``script``, kickoff. Returns the flow."""
flow = _ScriptedFlow()
flow._script = script
flow.kickoff()
return flow
class TestUsageDictToMetrics:
"""Unit tests for the dict-to-UsageMetrics normalizer."""
@pytest.mark.parametrize(
"usage, expected",
[
(None, None),
({}, None),
(
{"prompt_tokens": 10, "completion_tokens": 20, "total_tokens": 30},
UsageMetrics(
prompt_tokens=10,
completion_tokens=20,
total_tokens=30,
successful_requests=1,
),
),
# total_tokens missing → derived from prompt + completion
(
{"prompt_tokens": 4, "completion_tokens": 6},
UsageMetrics(
prompt_tokens=4,
completion_tokens=6,
total_tokens=10,
successful_requests=1,
),
),
# Extended provider-specific keys flow through normalization
(
{
"prompt_tokens": 100,
"completion_tokens": 80,
"total_tokens": 180,
"cached_prompt_tokens": 40,
"reasoning_tokens": 25,
"cache_creation_tokens": 10,
},
UsageMetrics(
prompt_tokens=100,
completion_tokens=80,
total_tokens=180,
cached_prompt_tokens=40,
reasoning_tokens=25,
cache_creation_tokens=10,
successful_requests=1,
),
),
# Garbage / non-int values coerce to 0 instead of crashing
(
{"prompt_tokens": "n/a", "completion_tokens": None, "total_tokens": 7},
UsageMetrics(
prompt_tokens=0,
completion_tokens=0,
total_tokens=0,
successful_requests=1,
),
),
# Native Anthropic provider emits input_tokens/output_tokens
(
{"input_tokens": 12, "output_tokens": 8},
UsageMetrics(
prompt_tokens=12,
completion_tokens=8,
total_tokens=20,
successful_requests=1,
),
),
# Native Gemini provider emits prompt_token_count/candidates_token_count
(
{
"prompt_token_count": 30,
"candidates_token_count": 20,
"reasoning_tokens": 5,
},
UsageMetrics(
prompt_tokens=30,
completion_tokens=20,
total_tokens=50,
reasoning_tokens=5,
successful_requests=1,
),
),
# OpenAI nests cached_tokens under prompt_tokens_details
(
{
"prompt_tokens": 100,
"completion_tokens": 50,
"prompt_tokens_details": {"cached_tokens": 30},
},
UsageMetrics(
prompt_tokens=100,
completion_tokens=50,
total_tokens=150,
cached_prompt_tokens=30,
successful_requests=1,
),
),
],
ids=[
"none",
"empty",
"all_keys",
"no_total",
"extended_keys",
"garbage",
"anthropic_aliases",
"gemini_aliases",
"openai_nested_cached",
],
)
def test_normalization(
self, usage: dict[str, Any] | None, expected: UsageMetrics | None
) -> None:
assert _usage_dict_to_metrics(usage) == expected
class TestFlowUsageAggregation:
"""End-to-end tests driving the listener through the real event bus."""
def test_sums_every_llm_call_in_the_flow(self) -> None:
"""Multiple LLM calls — including bare ``LLM.call(...)`` made outside
any crew — accumulate; ``successful_requests`` tracks the call count."""
def script(flow: Flow) -> None:
_emit_llm_call(flow_id=flow._flow_match_id, prompt_tokens=300, completion_tokens=300)
_emit_llm_call(flow_id=flow._flow_match_id, prompt_tokens=200, completion_tokens=100)
_emit_llm_call(flow_id=flow._flow_match_id, prompt_tokens=20, completion_tokens=20)
flow = _run(script)
assert flow.usage_metrics.total_tokens == 940
assert flow.usage_metrics.prompt_tokens == 520
assert flow.usage_metrics.completion_tokens == 420
assert flow.usage_metrics.successful_requests == 3
def test_returns_zero_when_no_calls_happen(self) -> None:
flow = _run()
assert flow.usage_metrics == UsageMetrics()
def test_ignores_events_from_other_flows(self) -> None:
"""Concurrent flow runs share the singleton bus, so the listener must
scope itself to its own flow via the contextvar match."""
def script(flow: Flow) -> None:
_emit_llm_call(flow_id=flow._flow_match_id, prompt_tokens=50, completion_tokens=50)
_emit_llm_call(flow_id="some-other-flow", prompt_tokens=49_000, completion_tokens=50_999)
flow = _run(script)
assert flow.usage_metrics.total_tokens == 100
assert flow.usage_metrics.successful_requests == 1
def test_resets_between_kickoffs(self) -> None:
flow = _ScriptedFlow()
flow._script = lambda f: _emit_llm_call(
flow_id=f._flow_match_id, prompt_tokens=250, completion_tokens=250
)
flow.kickoff()
flow.kickoff()
assert flow.usage_metrics.total_tokens == 500
assert flow.usage_metrics.successful_requests == 1
def test_usage_metrics_returns_independent_copy(self) -> None:
"""``usage_metrics`` must return a copy, not the internal instance —
otherwise callers can clobber the in-flight accumulator."""
flow = _run(
lambda f: _emit_llm_call(
flow_id=f._flow_match_id, prompt_tokens=50, completion_tokens=50
)
)
snapshot = flow.usage_metrics
snapshot.total_tokens = 999_999
assert flow.usage_metrics.total_tokens == 100
def test_handler_is_unregistered_after_kickoff(self) -> None:
"""Long-lived workers (Celery, devkit) must not leak one handler per
kickoff on the singleton bus, on either the success or failure path."""
def handler_count() -> int:
return len(
crewai_event_bus._sync_handlers.get(LLMCallCompletedEvent, frozenset())
)
before = handler_count()
flow = _ScriptedFlow()
flow._script = lambda f: _emit_llm_call(
flow_id=f._flow_match_id, prompt_tokens=5, completion_tokens=5
)
for _ in range(3):
flow.kickoff()
assert handler_count() == before
def boom(_f: Flow) -> None:
raise RuntimeError("boom")
failing = _ScriptedFlow()
failing._script = boom
with pytest.raises(RuntimeError, match="boom"):
failing.kickoff()
assert handler_count() == before
def test_kickoff_flushes_event_bus_before_returning(
self, monkeypatch: pytest.MonkeyPatch
) -> None:
"""`kickoff_async` must drain pending LLMCallCompletedEvent handlers
before detaching the listener — otherwise late handlers landing on
the threadpool would be lost on short flows. Mirrors the flush
``Crew.kickoff()`` performs before reporting ``token_usage``."""
flush_calls: list[None] = []
original_flush = crewai_event_bus.flush
def tracked_flush(*args: Any, **kwargs: Any) -> bool:
flush_calls.append(None)
return original_flush(*args, **kwargs)
monkeypatch.setattr(crewai_event_bus, "flush", tracked_flush)
flow = _ScriptedFlow()
flow._script = lambda f: _emit_llm_call(
flow_id=f._flow_match_id, prompt_tokens=3, completion_tokens=4
)
flow.kickoff()
assert flush_calls, "kickoff did not flush the event bus before returning"
assert flow.usage_metrics.total_tokens == 7
def test_stale_handler_from_prior_kickoff_does_not_contaminate(self) -> None:
"""A handler still queued from a prior kickoff must not write into
a later kickoff's accumulator. The handler's closure captures its
own accumulator object, so any late writes land on an orphaned
instance and the live ``usage_metrics`` is unaffected."""
captured: dict[str, Any] = {}
def script(flow: Flow) -> None:
_emit_llm_call(flow_id=flow._flow_match_id, prompt_tokens=10, completion_tokens=10)
captured["handler"] = flow._usage_aggregation_handler
captured["match_id"] = flow._flow_match_id
flow = _run(script)
assert flow.usage_metrics.total_tokens == 20
flow._script = lambda f: None
flow.kickoff()
assert flow.usage_metrics.total_tokens == 0
stale_handler = captured["handler"]
assert stale_handler is not None
stale_event = LLMCallCompletedEvent(
call_id=str(uuid4()),
model="gpt-4o-mini",
response="ok",
call_type=LLMCallType.LLM_CALL,
usage={"prompt_tokens": 999, "completion_tokens": 999, "total_tokens": 1998},
)
ctx = contextvars.copy_context()
ctx.run(lambda: (current_flow_id.set(captured["match_id"]), stale_handler(object(), stale_event)))
assert flow.usage_metrics.total_tokens == 0
def test_pause_detaches_listener_and_does_not_leak(self) -> None:
"""When ``kickoff_async`` pauses for human feedback, the listener
must be detached from the singleton bus to avoid leaking handlers
across abandoned paused instances. Pre-pause LLM events still
count because the bus snapshots handlers at emit time. Late
events emitted after the pause returns do not count for this
instance — resume paths re-attach a fresh listener."""
from crewai.flow.async_feedback.types import HumanFeedbackPending
captured: dict[str, Any] = {}
class _PausingFlow(Flow):
@start()
def begin(self) -> None:
_emit_llm_call(
flow_id=self._flow_match_id,
prompt_tokens=10,
completion_tokens=20,
)
captured["pre_pause_total"] = self.usage_metrics.total_tokens
raise HumanFeedbackPending(
context=PendingFeedbackContext(
flow_id=self.flow_id,
flow_class="_PausingFlow",
method_name="begin",
method_output="content",
message="Review:",
)
)
with tempfile.TemporaryDirectory() as tmpdir:
persistence = SQLiteFlowPersistence(os.path.join(tmpdir, "f.db"))
flow = _PausingFlow(persistence=persistence)
result = flow.kickoff()
assert isinstance(result, HumanFeedbackPending)
assert captured["pre_pause_total"] == 30
assert flow._usage_aggregation_handler is None
# A late event emitted after the pause does not reach the
# detached listener, so the running total is unchanged.
_emit_llm_call(
flow_id=flow._flow_match_id,
prompt_tokens=2,
completion_tokens=3,
)
assert flow.usage_metrics.total_tokens == 30
def test_aggregates_resume_after_from_pending(self) -> None:
"""A flow restored via ``from_pending`` is a fresh instance with no
``_flow_match_id``; without seeding it, the listener attached in
``resume_async`` either ignores its own LLM calls or absorbs unrelated
ones. ``from_pending`` must seed the match id so the resume-phase
aggregator counts our own calls and only our own calls."""
class _ResumeFlow(Flow):
@start()
def begin(self) -> str:
return "content"
@listen(begin)
def on_begin(self, _feedback: Any) -> str:
_emit_llm_call(
flow_id=self._flow_match_id,
prompt_tokens=100,
completion_tokens=50,
)
_emit_llm_call(
flow_id="some-other-flow",
prompt_tokens=9_999,
completion_tokens=9_999,
)
return "done"
with tempfile.TemporaryDirectory() as tmpdir:
persistence = SQLiteFlowPersistence(os.path.join(tmpdir, "f.db"))
flow_id = "usage-resume-test"
persistence.save_pending_feedback(
flow_uuid=flow_id,
context=PendingFeedbackContext(
flow_id=flow_id,
flow_class="_ResumeFlow",
method_name="begin",
method_output="content",
message="Review:",
),
state_data={"id": flow_id},
)
flow = _ResumeFlow.from_pending(flow_id, persistence)
assert flow._flow_match_id == flow.flow_id
flow.resume("ok")
assert flow.usage_metrics.total_tokens == 150
assert flow.usage_metrics.prompt_tokens == 100
assert flow.usage_metrics.completion_tokens == 50
assert flow.usage_metrics.successful_requests == 1
def test_resume_aggregates_under_foreign_flow_context(self) -> None:
"""Resume must override an already-set ``current_flow_id`` so its
own LLM events match the listener's filter even when invoked from
inside another flow's active context."""
class _ResumeFlow(Flow):
@start()
def begin(self) -> str:
return "content"
@listen(begin)
def on_begin(self, _feedback: Any) -> str:
_emit_llm_call(
flow_id=self._flow_match_id,
prompt_tokens=42,
completion_tokens=8,
)
return "done"
with tempfile.TemporaryDirectory() as tmpdir:
persistence = SQLiteFlowPersistence(os.path.join(tmpdir, "f.db"))
flow_id = "resume-foreign-context"
persistence.save_pending_feedback(
flow_uuid=flow_id,
context=PendingFeedbackContext(
flow_id=flow_id,
flow_class="_ResumeFlow",
method_name="begin",
method_output="content",
message="Review:",
),
state_data={"id": flow_id},
)
foreign_token = current_flow_id.set("some-parent-flow")
try:
flow = _ResumeFlow.from_pending(flow_id, persistence)
flow.resume("ok")
finally:
current_flow_id.reset(foreign_token)
assert flow.usage_metrics.total_tokens == 50
assert flow.usage_metrics.successful_requests == 1