Release v3.12.0 (#971)

Author: alexmojaki

CHANGELOG.md

@@ -1,5 +1,12 @@
 # Release Notes
 
+## [v3.12.0] (2025-03-31)
+
+* Add `logfire.instrument_mcp()` method by @alexmojaki in [#966](https://github.com/pydantic/logfire/pull/966)
+* Merge headers if passed via `client_kwargs` in query client by @Kludex in [#958](https://github.com/pydantic/logfire/pull/958)
+* Warn user if f-string expression contains `await` by @Sbargaoui in [#944](https://github.com/pydantic/logfire/pull/944)
+* Handle new MCP span in OpenAI Agents SDK by @alexmojaki in [#963](https://github.com/pydantic/logfire/pull/963)
+
 ## [v3.11.0] (2025-03-26)
 
 * Add `record_return` flag to `@logfire.instrument` by @alexmojaki in [#955](https://github.com/pydantic/logfire/pull/955)
@@ -649,3 +656,4 @@ First release from new repo!
 [v3.9.1]: https://github.com/pydantic/logfire/compare/v3.9.0...v3.9.1
 [v3.10.0]: https://github.com/pydantic/logfire/compare/v3.9.1...v3.10.0
 [v3.11.0]: https://github.com/pydantic/logfire/compare/v3.10.0...v3.11.0
+[v3.12.0]: https://github.com/pydantic/logfire/compare/v3.11.0...v3.12.0

logfire-api/logfire_api/__init__.pyi

@@ -13,7 +13,7 @@ from .version import VERSION as VERSION
 from logfire.sampling import SamplingOptions as SamplingOptions
 from typing import Any
 
-__all__ = ['Logfire', 'LogfireSpan', 'LevelName', 'AdvancedOptions', 'ConsoleOptions', 'CodeSource', 'PydanticPlugin', 'configure', 'span', 'instrument', 'log', 'trace', 'debug', 'notice', 'info', 'warn', 'warning', 'error', 'exception', 'fatal', 'force_flush', 'log_slow_async_callbacks', 'install_auto_tracing', 'instrument_asgi', 'instrument_wsgi', 'instrument_pydantic', 'instrument_pydantic_ai', 'instrument_fastapi', 'instrument_openai', 'instrument_openai_agents', 'instrument_anthropic', 'instrument_asyncpg', 'instrument_httpx', 'instrument_celery', 'instrument_requests', 'instrument_psycopg', 'instrument_django', 'instrument_flask', 'instrument_starlette', 'instrument_aiohttp_client', 'instrument_sqlalchemy', 'instrument_sqlite3', 'instrument_aws_lambda', 'instrument_redis', 'instrument_pymongo', 'instrument_mysql', 'instrument_system_metrics', 'AutoTraceModule', 'with_tags', 'with_settings', 'suppress_scopes', 'shutdown', 'no_auto_trace', 'ScrubMatch', 'ScrubbingOptions', 'VERSION', 'add_non_user_code_prefix', 'suppress_instrumentation', 'StructlogProcessor', 'LogfireLoggingHandler', 'loguru_handler', 'SamplingOptions', 'MetricsOptions', 'logfire_info']
+__all__ = ['Logfire', 'LogfireSpan', 'LevelName', 'AdvancedOptions', 'ConsoleOptions', 'CodeSource', 'PydanticPlugin', 'configure', 'span', 'instrument', 'log', 'trace', 'debug', 'notice', 'info', 'warn', 'warning', 'error', 'exception', 'fatal', 'force_flush', 'log_slow_async_callbacks', 'install_auto_tracing', 'instrument_asgi', 'instrument_wsgi', 'instrument_pydantic', 'instrument_pydantic_ai', 'instrument_fastapi', 'instrument_openai', 'instrument_openai_agents', 'instrument_anthropic', 'instrument_asyncpg', 'instrument_httpx', 'instrument_celery', 'instrument_requests', 'instrument_psycopg', 'instrument_django', 'instrument_flask', 'instrument_starlette', 'instrument_aiohttp_client', 'instrument_sqlalchemy', 'instrument_sqlite3', 'instrument_aws_lambda', 'instrument_redis', 'instrument_pymongo', 'instrument_mysql', 'instrument_system_metrics', 'instrument_mcp', 'AutoTraceModule', 'with_tags', 'with_settings', 'suppress_scopes', 'shutdown', 'no_auto_trace', 'ScrubMatch', 'ScrubbingOptions', 'VERSION', 'add_non_user_code_prefix', 'suppress_instrumentation', 'StructlogProcessor', 'LogfireLoggingHandler', 'loguru_handler', 'SamplingOptions', 'MetricsOptions', 'logfire_info']
 
 DEFAULT_LOGFIRE_INSTANCE = Logfire()
 span = DEFAULT_LOGFIRE_INSTANCE.span
@@ -45,6 +45,7 @@ instrument_redis = DEFAULT_LOGFIRE_INSTANCE.instrument_redis
 instrument_pymongo = DEFAULT_LOGFIRE_INSTANCE.instrument_pymongo
 instrument_mysql = DEFAULT_LOGFIRE_INSTANCE.instrument_mysql
 instrument_system_metrics = DEFAULT_LOGFIRE_INSTANCE.instrument_system_metrics
+instrument_mcp = DEFAULT_LOGFIRE_INSTANCE.instrument_mcp
 suppress_scopes = DEFAULT_LOGFIRE_INSTANCE.suppress_scopes
 shutdown = DEFAULT_LOGFIRE_INSTANCE.shutdown
 with_tags = DEFAULT_LOGFIRE_INSTANCE.with_tags

logfire-api/logfire_api/_internal/exporters/quiet_metrics.pyi

@@ -1,6 +1,5 @@
 from .wrapper import WrapperMetricExporter as WrapperMetricExporter
-from opentelemetry.sdk.metrics._internal.export import MetricExportResult
-from opentelemetry.sdk.metrics._internal.point import MetricsData
+from opentelemetry.sdk.metrics.export import MetricExportResult, MetricsData
 from typing import Any
 
 class QuietMetricExporter(WrapperMetricExporter):

logfire-api/logfire_api/_internal/formatter.pyi

@@ -54,6 +54,13 @@ class KnownFormattingError(Exception):
     In other words this should correspond to errors that would be raised when using `str.format`,
     and generally indicate a user error, most likely that they weren't trying to pass a template string at all.
     """
+class FStringAwaitError(Exception):
+    """An error raised when an await expression is found in an f-string.
+
+    This is a specific case that can't be handled by f-string introspection and requires
+    pre-evaluating the await expression before logging.
+    """
 class FormattingFailedWarning(UserWarning): ...
 
 def warn_formatting(msg: str): ...
+def warn_fstring_await(msg: str): ...

logfire-api/logfire_api/_internal/integrations/mcp.pyi

@@ -0,0 +1,3 @@
+from logfire import Logfire as Logfire
+
+def instrument_mcp(logfire_instance: Logfire): ...

logfire-api/logfire_api/_internal/integrations/openai_agents.pyi

@@ -1,10 +1,10 @@
 import contextvars
 from _typeshed import Incomplete
 from abc import abstractmethod
-from agents import Span, Trace
+from agents import Span, SpanData, Trace
 from agents.tracing import ResponseSpanData
 from agents.tracing.setup import TraceProvider
-from agents.tracing.spans import SpanData, SpanError, TSpanData
+from agents.tracing.spans import SpanError, TSpanData
 from dataclasses import dataclass
 from logfire import Logfire as Logfire, LogfireSpan as LogfireSpan
 from logfire._internal.formatter import logfire_format as logfire_format

logfire-api/logfire_api/_internal/main.pyi

@@ -401,6 +401,8 @@ class Logfire:
                 modules in `sys.modules` (i.e. modules that have already been imported) match the modules to trace.
                 Set to `'warn'` to issue a warning instead, or `'ignore'` to skip the check.
         """
+    def instrument_mcp(self) -> None:
+        """Instrument [MCP](https://modelcontextprotocol.io/) requests such as tool calls."""
     def instrument_pydantic(self, record: PydanticPluginRecordValues = 'all', include: Iterable[str] = (), exclude: Iterable[str] = ()) -> None:
         """Instrument Pydantic model validations.
 

logfire-api/pyproject.toml

@@ -4,7 +4,7 @@ build-backend = "hatchling.build"
 
 [project]
 name = "logfire-api"
-version = "3.11.0"
+version = "3.12.0"
 description = "Shim for the Logfire SDK which does nothing unless Logfire is installed"
 authors = [
     { name = "Pydantic Team", email = "[email protected]" },

pyproject.toml

@@ -4,7 +4,7 @@ build-backend = "hatchling.build"
 
 [project]
 name = "logfire"
-version = "3.11.0"
+version = "3.12.0"
 description = "The best Python observability tool! 🪵🔥"
 requires-python = ">=3.8"
 authors = [