diff --git a/src/agent_comms/cli_commands.py b/src/agent_comms/cli_commands.py
index 3746e33285..1f38224f21 100644
--- a/src/agent_comms/cli_commands.py
+++ b/src/agent_comms/cli_commands.py
@@ -455,7 +455,7 @@ def apply_together(cls, ctx: Comms, commands: tuple[Self, ...]) -> tuple[CliResu
 
 
 @dataclass(frozen=True)
-class TargetEdit(Command):
+class TargetEdit(Command[Comms, CliResult]):
     """Accepted editor values use the declared field and current bound command."""
     declaration: type[CliCommand]
     target: TargetSelection
@@ -746,7 +746,7 @@ class NativeContextInspection(CliResult):
     native_source_spans: tuple[NativeSourceSpans, ...]
 
 
-class CliExecution(Command):
+class CliExecution[Answer: CliResult = CliResult](Command[Comms, Answer]):
     """The dispatcher contract, including methods selected through multiple inheritance."""
 
     @abstractmethod
@@ -801,7 +801,7 @@ class WorktreeArgument:
 class CliCommand[Answer: CliResult = CliResult](
     DeclaredFamily,
     DeclaredOptions,
-    CliExecution,
+    CliExecution[Answer],
     affix="CliCommand",
     discovery_package="agent_comms.tools",
 ):
diff --git a/src/agent_comms/cli_native_package.py b/src/agent_comms/cli_native_package.py
index 3501da3ab3..9ef34eb18c 100644
--- a/src/agent_comms/cli_native_package.py
+++ b/src/agent_comms/cli_native_package.py
@@ -23,7 +23,7 @@
 
 
 @dataclass(frozen=True, kw_only=True)
-class NativePackageVerb(DeclaredVerb, Command, affix="Verb"):
+class NativePackageVerb(DeclaredVerb, Command[None, None], affix="Verb"):
     """One verb: its fields declare its parser, and apply() does the work."""
 
     @abstractmethod
diff --git a/src/agent_comms/command.py b/src/agent_comms/command.py
index 4b28458722..445f6040ed 100644
--- a/src/agent_comms/command.py
+++ b/src/agent_comms/command.py
@@ -1,18 +1,18 @@
 """Inbound command contract; domain roots reuse DeclaredFamily and FieldCodec."""
 
 from abc import ABC, abstractmethod
-from typing import Any, Self
+from typing import Self
 
 from pydantic import JsonValue
 
 from .field_codec import FieldCodec
 
 
-class Command(ABC):
+class Command[Context, Result](ABC):
     @classmethod
     def from_payload(cls, payload: dict[str, JsonValue]) -> Self:
         return FieldCodec.decode(cls, payload)
 
     @abstractmethod
-    def apply(self, ctx: Any) -> Any:
+    def apply(self, ctx: Context) -> Result:
         """Apply the command using its domain's shared preconditions."""
diff --git a/src/agent_comms/connector.py b/src/agent_comms/connector.py
index 199b20792a..a7d3d0354a 100644
--- a/src/agent_comms/connector.py
+++ b/src/agent_comms/connector.py
@@ -833,7 +833,7 @@ async def mcp(self, request: web.Request) -> web.Response:
 
 @dataclass(frozen=True, kw_only=True)
 class ConnectorVerb(
-    DeclaredVerb, Command,
+    DeclaredVerb, Command[ConnectorStore, int | str],
     affix="Verb", discovery_package=HostService.__module__,
 ):
     """One connector command: its options are its fields, and its parser comes from them."""
diff --git a/src/agent_comms/goal_actions.py b/src/agent_comms/goal_actions.py
index 38c3bb83eb..0eebe859cf 100644
--- a/src/agent_comms/goal_actions.py
+++ b/src/agent_comms/goal_actions.py
@@ -113,7 +113,9 @@ def model_report(self) -> bool:
 
 
 @dataclass(frozen=True, kw_only=True)
-class GoalAction[Result: GoalDeclaration](DeclaredFamily, Command, affix="GoalAction"):
+class GoalAction[Result: GoalDeclaration](
+    DeclaredFamily, Command[GoalActionContext, Result], affix="GoalAction"
+):
     expect: GoalPrecondition = GoalPrecondition()
     preserve_wait: ClassVar[bool] = False
     schedules_goal: ClassVar[bool] = False
diff --git a/src/agent_comms/queued_input.py b/src/agent_comms/queued_input.py
index cba36e0582..702cb61a88 100644
--- a/src/agent_comms/queued_input.py
+++ b/src/agent_comms/queued_input.py
@@ -11,7 +11,7 @@
 from contextlib import AsyncExitStack, ExitStack, asynccontextmanager
 from dataclasses import dataclass, field, replace
 from functools import partial
-from typing import TYPE_CHECKING, Any, Generic, Self, TypeVar
+from typing import TYPE_CHECKING, Generic, Self, TypeVar
 
 from acp import RequestError
 
diff --git a/src/agent_comms/relationships.py b/src/agent_comms/relationships.py
index 85f38e90f7..3c6f197cc2 100644
--- a/src/agent_comms/relationships.py
+++ b/src/agent_comms/relationships.py
@@ -579,7 +579,7 @@ def require_peer(self) -> Thread:
             )
         return self.second
 
-    def publish(self, changed: Collaboration):
+    def publish(self, changed: Collaboration) -> tuple[RelationshipDocument, Collaboration]:
         active = self.active
         if changed is active:
             return self.document, changed.oriented(self.first)
@@ -593,19 +593,19 @@ def publish(self, changed: Collaboration):
 
 
 @dataclass(frozen=True)
-class RelationshipEdit(Command, DeclaredFamily, affix="RelationshipEdit"):
+class RelationshipEdit[Result](
+    Command[RelationshipEditContext, tuple[RelationshipDocument, Result]],
+    DeclaredFamily, affix="RelationshipEdit",
+):
     note: str = ""
 
     def __post_init__(self):
         if len(self.note) > 2000:
             raise ValueError("Collaboration notes are limited to 2000 characters")
 
-    @abstractmethod
-    def apply(self, ctx: RelationshipEditContext): ...
-
 
-class RetainingRelationshipEdit(RelationshipEdit):
-    def apply(self, ctx: RelationshipEditContext):
+class RetainingRelationshipEdit(RelationshipEdit[Collaboration]):
+    def apply(self, ctx: RelationshipEditContext) -> tuple[RelationshipDocument, Collaboration]:
         peer = ctx.require_peer()
         return ctx.publish(self.change(ctx, peer))
 
@@ -631,8 +631,8 @@ def change(self, ctx: RelationshipEditContext, peer: Thread) -> Collaboration:
         return active.updated(self.note, time.time())
 
 
-class RemoveRelationshipEdit(RelationshipEdit):
-    def apply(self, ctx: RelationshipEditContext):
+class RemoveRelationshipEdit(RelationshipEdit[None]):
+    def apply(self, ctx: RelationshipEditContext) -> tuple[RelationshipDocument, None]:
         existing = ctx.existing
         if existing is None:
             return ctx.document, None
diff --git a/src/agent_comms/runtime_requests.py b/src/agent_comms/runtime_requests.py
index 5d7617ca27..0ee568addd 100644
--- a/src/agent_comms/runtime_requests.py
+++ b/src/agent_comms/runtime_requests.py
@@ -10,7 +10,7 @@
 import asyncio
 import json
 from abc import abstractmethod
-from collections.abc import AsyncIterator
+from collections.abc import AsyncIterator, Awaitable
 from contextlib import asynccontextmanager
 from dataclasses import dataclass
 from functools import partial
@@ -67,7 +67,9 @@ async def send(self, line: OwnerLine) -> None:
 
 
 @dataclass(frozen=True, kw_only=True)
-class RuntimeRequest(DeclaredFamily, Command, affix="RuntimeRequest"):
+class RuntimeRequest(
+    DeclaredFamily, Command[RuntimeRequestContext, Awaitable[None]], affix="RuntimeRequest"
+):
     thread: str
 
     @classmethod
diff --git a/src/agent_comms/session_lifecycle.py b/src/agent_comms/session_lifecycle.py
index 12a38cb1a9..54ddcd0b6a 100644
--- a/src/agent_comms/session_lifecycle.py
+++ b/src/agent_comms/session_lifecycle.py
@@ -6,7 +6,7 @@
 import os
 from functools import partial
 from pathlib import Path
-from typing import Any, cast
+from typing import cast
 
 from acp import RequestError
 from acp.schema import (
diff --git a/src/agent_comms/todos.py b/src/agent_comms/todos.py
index a0c5ec57d2..57f370c96a 100644
--- a/src/agent_comms/todos.py
+++ b/src/agent_comms/todos.py
@@ -2739,8 +2739,12 @@ def closed(cls, current: Todo, order: ProblemOrder) -> Todo:
                        revision=current.revision + 1)
 
 
+# Todo stores these commands, so it is declared after them; the alias reads it lazily.
+type CommandedTodo = Todo
+
+
 @dataclass(frozen=True)
-class TodoCommand(Command, DeclaredFamily, affix="TodoOperation"):
+class TodoCommand(Command[CommandedTodo, CommandedTodo], DeclaredFamily, affix="TodoOperation"):
     expected_revision: int
 
     def __post_init__(self) -> None:
diff --git a/tools/debt_ratchet.py b/tools/debt_ratchet.py
index 029e0aad6a..16a88b7fc9 100644
--- a/tools/debt_ratchet.py
+++ b/tools/debt_ratchet.py
@@ -419,9 +419,10 @@ def sites(tree: ast.AST, filename: str) -> Iterator[ast.AST]:
 
     @staticmethod
     def occurrences(node: ast.AST) -> int:
-        metadata = typing.cast(
-            types.MemberDescriptorType, typing.cast(typing.Any, dataclasses.Field).metadata
-        ).__name__
+        descriptor: types.MemberDescriptorType = inspect.getattr_static(
+            dataclasses.Field, "metadata"
+        )
+        metadata = descriptor.__name__
         return sum(
             typing.cast(int, MetadataKeys().visit(keyword.value))
             for keyword in typing.cast(ast.Call, node).keywords