diff --git a/docs/introduction/configuration.md b/docs/introduction/configuration.md
index 4742be6..b735811 100644
--- a/docs/introduction/configuration.md
+++ b/docs/introduction/configuration.md
@@ -31,7 +31,7 @@ Additional parameters can also be supplied through the settings object:
 - `sentry_traces_sample_rate` - in the range of 0.0 to 1.0, the percentage chance a given transaction will be sent 
 - `sentry_sample_rate` - in the range of 0.0 to 1.0, the sample rate for error events
 - `sentry_max_breadcrumbs` - the total amount of breadcrumbs
-- `sentry_max_value_length` - the max event payload length
+- `sentry_max_value_length` - the maximum length of each string value before sentry-sdk truncates it
 - `sentry_attach_stacktrace` - if True, stack traces are automatically attached to all messages logged
 - `sentry_auto_session_tracking` - whether every request opens and closes a Sentry release-health `Session` (default: `False`), measured at ~7.7 µs per request. Set it to `True` if you use Sentry release health: crash-free session and user rates need it.
 - `sentry_integrations` - list of integrations to enable
@@ -346,7 +346,7 @@ See [Performance](performance.md).
 Additional parameters:
 
 - `logging_enabled` - whether to configure structlog (default: `True`).
-- `logging_log_level`
+- `logging_log_level` - the root logger level set at bootstrap (default: `logging.INFO`).
 - `logging_extra_processors`
 - `logging_unset_handlers` - logger names whose handlers are cleared at bootstrap. These removals are permanent.
 - `logging_record_filters` - standard-library `logging.Filter` instances to attach to named loggers (see below).
@@ -538,8 +538,6 @@ from lite_bootstrap import InstrumentDependencyMissingWarning
 warnings.filterwarnings("ignore", category=InstrumentDependencyMissingWarning)
 ```
 
-`InstrumentSkippedWarning` is kept as the base class for forward-compatibility (additional skip categories may emerge); today, `InstrumentDependencyMissingWarning` is its only concrete subclass.
-
 To inspect skipped instruments programmatically:
 
 ```python
diff --git a/docs/migration/to-2.x.md b/docs/migration/to-2.x.md
index e0dfe6d..fada91f 100644
--- a/docs/migration/to-2.x.md
+++ b/docs/migration/to-2.x.md
@@ -26,3 +26,20 @@ traffic mix.
 JSON log lines include `tracing` only when emitted inside a recording
 OpenTelemetry span. The object contains `span_id` and `trace_id`.
 Update log parsers to treat `tracing` as optional.
+
+## Missing-dependency warning category
+
+`InstrumentSkippedWarning` has been removed. Importing it from `lite_bootstrap`
+now raises `ImportError`. Replace imports and warning filters with
+`InstrumentDependencyMissingWarning`, which now derives directly from `UserWarning`:
+
+```python
+import warnings
+
+from lite_bootstrap import InstrumentDependencyMissingWarning
+
+warnings.filterwarnings("error", category=InstrumentDependencyMissingWarning)
+```
+
+Unconfigured instruments continue to be skipped silently. A configured instrument
+with a missing optional dependency emits `InstrumentDependencyMissingWarning`.
diff --git a/lite_bootstrap/__init__.py b/lite_bootstrap/__init__.py
index 24a036a..372f3ed 100644
--- a/lite_bootstrap/__init__.py
+++ b/lite_bootstrap/__init__.py
@@ -7,7 +7,6 @@
     BootstrapperNotReadyError,
     ConfigurationError,
     InstrumentDependencyMissingWarning,
-    InstrumentSkippedWarning,
     LiteBootstrapError,
     TeardownError,
 )
@@ -26,7 +25,6 @@
     "FreeBootstrapper",
     "FreeConfig",
     "InstrumentDependencyMissingWarning",
-    "InstrumentSkippedWarning",
     "LiteBootstrapError",
     "LitestarBootstrapper",
     "LitestarConfig",
diff --git a/lite_bootstrap/bootstrappers/fastapi_bootstrapper.py b/lite_bootstrap/bootstrappers/fastapi_bootstrapper.py
index e7626c7..146f4ff 100644
--- a/lite_bootstrap/bootstrappers/fastapi_bootstrapper.py
+++ b/lite_bootstrap/bootstrappers/fastapi_bootstrapper.py
@@ -296,8 +296,6 @@ def bootstrap(self) -> None:
 
 
 class FastAPIBootstrapper(BaseBootstrapper["fastapi.FastAPI", FastAPIConfig]):
-    __slots__ = "bootstrap_config", "instruments"
-
     instruments_types: typing.ClassVar = [
         FastAPICorsInstrument,
         FastAPIOpenTelemetryInstrument,
diff --git a/lite_bootstrap/bootstrappers/fastmcp_bootstrapper.py b/lite_bootstrap/bootstrappers/fastmcp_bootstrapper.py
index 494ffc3..b418997 100644
--- a/lite_bootstrap/bootstrappers/fastmcp_bootstrapper.py
+++ b/lite_bootstrap/bootstrappers/fastmcp_bootstrapper.py
@@ -370,8 +370,6 @@ def bootstrap(self) -> None:
 
 
 class FastMcpBootstrapper(BaseBootstrapper["FastMCP[typing.Any]", FastMcpConfig]):
-    __slots__ = "bootstrap_config", "instruments"
-
     instruments_types: typing.ClassVar = [
         FastMcpOpenTelemetryInstrument,
         PyroscopeInstrument,
diff --git a/lite_bootstrap/bootstrappers/faststream_bootstrapper.py b/lite_bootstrap/bootstrappers/faststream_bootstrapper.py
index e7e7dc0..3650229 100644
--- a/lite_bootstrap/bootstrappers/faststream_bootstrapper.py
+++ b/lite_bootstrap/bootstrappers/faststream_bootstrapper.py
@@ -54,7 +54,6 @@ async def after_processed(
     tracer: typing.Final = trace.get_tracer(__name__)
 
 
-@typing.runtime_checkable
 class FastStreamTelemetryMiddlewareProtocol(typing.Protocol):
     def __init__(
         self,
@@ -71,7 +70,6 @@ def __init__(
     def __call__(self, msg: typing.Any, /, *, context: typing.Any) -> typing.Any: ...  # noqa: ANN401
 
 
-@typing.runtime_checkable
 class FastStreamPrometheusMiddlewareProtocol(typing.Protocol):
     def __init__(
         self,
@@ -266,8 +264,6 @@ def bootstrap(self) -> None:
 
 
 class FastStreamBootstrapper(BaseBootstrapper["AsgiFastStream", FastStreamConfig]):
-    __slots__ = "bootstrap_config", "instruments"
-
     instruments_types: typing.ClassVar = [
         FastStreamOpenTelemetryInstrument,
         PyroscopeInstrument,
diff --git a/lite_bootstrap/bootstrappers/free_bootstrapper.py b/lite_bootstrap/bootstrappers/free_bootstrapper.py
index 2428ab5..95edb0a 100644
--- a/lite_bootstrap/bootstrappers/free_bootstrapper.py
+++ b/lite_bootstrap/bootstrappers/free_bootstrapper.py
@@ -13,8 +13,6 @@ class FreeConfig(LoggingConfig, OpenTelemetryConfig, PyroscopeConfig, SentryConf
 
 
 class FreeBootstrapper(BaseBootstrapper[None, FreeConfig]):
-    __slots__ = "bootstrap_config", "instruments"
-
     instruments_types: typing.ClassVar = [
         LoggingInstrument,
         SentryInstrument,
diff --git a/lite_bootstrap/bootstrappers/litestar_bootstrapper.py b/lite_bootstrap/bootstrappers/litestar_bootstrapper.py
index 4a2acea..9df237f 100644
--- a/lite_bootstrap/bootstrappers/litestar_bootstrapper.py
+++ b/lite_bootstrap/bootstrappers/litestar_bootstrapper.py
@@ -485,8 +485,6 @@ def bootstrap(self) -> None:
 
 
 class LitestarBootstrapper(BaseBootstrapper["litestar.Litestar", LitestarConfig]):
-    __slots__ = "bootstrap_config", "instruments"
-
     instruments_types: typing.ClassVar = [
         LitestarCorsInstrument,
         LitestarOpenTelemetryInstrument,
diff --git a/lite_bootstrap/exceptions.py b/lite_bootstrap/exceptions.py
index c90ab62..ac7dba7 100644
--- a/lite_bootstrap/exceptions.py
+++ b/lite_bootstrap/exceptions.py
@@ -12,10 +12,11 @@ class BootstrapperNotReadyError(LiteBootstrapError):
 
 
 class ConfigurationError(LiteBootstrapError):
-    """Raised when a config is invalid or a required optional dependency is missing.
+    """Raised for invalid configuration or when bootstrap() cannot use the application.
 
-    Also raised when a bootstrapper is constructed on an application another bootstrapper
-    already owns.
+    bootstrap() rejects an application owned by another bootstrapper and refuses to reuse
+    a bootstrapper after teardown or a failed bootstrap. Missing optional dependencies warn
+    instead, as does construction on an application another bootstrapper already owns.
     """
 
 
@@ -28,11 +29,7 @@ def __init__(self, errors: list[tuple[str, BaseException]]) -> None:
         super().__init__(f"{len(errors)} instrument(s) failed during teardown: {details}")
 
 
-class InstrumentSkippedWarning(UserWarning):
-    """Base class for warnings emitted when an instrument is skipped during bootstrap."""
-
-
-class InstrumentDependencyMissingWarning(InstrumentSkippedWarning):
+class InstrumentDependencyMissingWarning(UserWarning):
     """Emitted when an instrument is skipped because its optional dependency is not installed."""
 
 
diff --git a/pyproject.toml b/pyproject.toml
index d2f42f7..d9f4122 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -169,7 +169,6 @@ faststream-metrics = [
 ]
 faststream-all = [
     "lite-bootstrap[faststream-sentry,faststream-otl,faststream-logging,faststream-metrics,pyroscope]",
-    "lite-bootstrap[sentry,otl,logging,faststream,faststream-metrics,pyroscope]"
 ]
 fastmcp = [
     # >=4.0 so one middleware dispatch model is supported: from 4.0 the access log's on_message sees
diff --git a/scripts/floor_smoke.py b/scripts/floor_smoke.py
index 65ef1cf..af5414d 100644
--- a/scripts/floor_smoke.py
+++ b/scripts/floor_smoke.py
@@ -9,7 +9,7 @@
 config with every instrument its extras can supply, bootstraps, exercises the calls
 that set a floor, and tears down.
 
-`InstrumentSkippedWarning` is escalated to an error, because an instrument that
+`InstrumentDependencyMissingWarning` is escalated to an error, because an instrument that
 degrades to a silent skip would let a too-low floor pass as success.
 
 Not a pytest test: conftest.py hard-imports opentelemetry, sentry_sdk and structlog,
@@ -31,7 +31,7 @@
     FastStreamConfig,
     FreeBootstrapper,
     FreeConfig,
-    InstrumentSkippedWarning,
+    InstrumentDependencyMissingWarning,
     LitestarBootstrapper,
     LitestarConfig,
     import_checker,
@@ -338,7 +338,7 @@ def main() -> None:
     expected_argv_len = 2
     if len(sys.argv) != expected_argv_len or sys.argv[1] not in TARGETS:
         sys.exit(f"usage: floor_smoke.py {{{'|'.join(TARGETS)}}}")
-    warnings.filterwarnings("error", category=InstrumentSkippedWarning)
+    warnings.filterwarnings("error", category=InstrumentDependencyMissingWarning)
     target = sys.argv[1]
     TARGETS[target]()
     print(f"floor smoke OK: {target} on {sys.version}")  # noqa: T201
diff --git a/tests/conftest.py b/tests/conftest.py
index 605ad42..f5b7541 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -24,18 +24,18 @@
 from structlog.typing import EventDict, WrappedLogger
 
 from lite_bootstrap import import_checker
-from lite_bootstrap.exceptions import InstrumentSkippedWarning
+from lite_bootstrap.exceptions import InstrumentDependencyMissingWarning
 from lite_bootstrap.instruments import healthchecks_instrument, opentelemetry_instrument
 
 
 def pytest_configure() -> None:
-    """Escalate InstrumentSkippedWarning (and subclasses) to errors.
+    """Escalate InstrumentDependencyMissingWarning (and subclasses) to errors.
 
     Done here rather than via filterwarnings in pyproject.toml to avoid pytest
     resolving the warning class before pytest-cov starts coverage, which would
     cause coverage to miss the lite_bootstrap module-level statements.
     """
-    warnings.filterwarnings("error", category=InstrumentSkippedWarning)
+    warnings.filterwarnings("error", category=InstrumentDependencyMissingWarning)
 
 
 class CustomInstrumentor(BaseInstrumentor):