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+Feature: M6 autonomy acceptance smoke tests
+  As a developer working with the CleverAgents M6 milestone (v3.5.0)
+  I want to verify the A2A facade, event queue, guard enforcement, and
+  automation profile resolution end-to-end
+  So that all v3.5.0 acceptance criteria are satisfied before milestone closure
+
+  Background:
+    Given a m6 smoke test runner
+    And a m6 smoke A2A local facade
+
+  # --- Fixture loading ---
+
+  Scenario: M6 smoke load A2A facade flows fixture
+    When I m6 smoke load the A2A facade flows fixture
+    Then the m6 smoke facade fixture should have a session lifecycle entry
+    And the m6 smoke facade fixture should have a plan lifecycle entry
+
+  Scenario: M6 smoke load autonomy guardrails fixture
+    When I m6 smoke load the autonomy guardrails fixture
+    Then the m6 smoke guardrails fixture should have a denylist entry
+    And the m6 smoke guardrails fixture should have an allowlist entry
+    And the m6 smoke guardrails fixture should have a cost budget entry
+
+  Scenario: M6 smoke load automation profiles fixture
+    When I m6 smoke load the automation profiles fixture
+    Then the m6 smoke profiles fixture should list all 8 built-in names
+    And the m6 smoke profiles fixture should have a custom profile entry
+
+  # --- A2A facade session operations (AC-1: session lifecycle) ---
+
+  Scenario: M6 smoke A2A session create returns session id
+    When I m6 smoke dispatch "session.create" with params {}
+    Then the m6 smoke response status should be "ok"
+    And the m6 smoke response data should contain key "session_id"
+    And the m6 smoke response data should contain key "status"
+
+  Scenario: M6 smoke A2A session close returns closed status
+    When I m6 smoke dispatch "session.close" with params {}
+    Then the m6 smoke response status should be "ok"
+    And the m6 smoke response data "status" should equal "closed"
+
+  # --- A2A facade plan operations (AC-1: plan lifecycle) ---
+
+  Scenario: M6 smoke A2A plan create returns plan id
+    When I m6 smoke dispatch "plan.create" with params {}
+    Then the m6 smoke response status should be "ok"
+    And the m6 smoke response data should contain key "plan_id"
+
+  Scenario: M6 smoke A2A plan execute queues plan
+    When I m6 smoke dispatch "plan.execute" with params {"plan_id": "01M6SM0KE00000000000000001"}
+    Then the m6 smoke response status should be "ok"
+    And the m6 smoke response data "status" should equal "queued"
+
+  Scenario: M6 smoke A2A plan status returns phase
+    When I m6 smoke dispatch "plan.status" with params {"plan_id": "01M6SM0KE00000000000000001"}
+    Then the m6 smoke response status should be "ok"
+    And the m6 smoke response data should contain key "phase"
+
+  Scenario: M6 smoke A2A plan diff returns changes list
+    When I m6 smoke dispatch "plan.diff" with params {"plan_id": "01M6SM0KE00000000000000001"}
+    Then the m6 smoke response status should be "ok"
+    And the m6 smoke response data should contain key "changes"
+
+  Scenario: M6 smoke A2A plan apply returns applied status
+    When I m6 smoke dispatch "plan.apply" with params {"plan_id": "01M6SM0KE00000000000000001"}
+    Then the m6 smoke response status should be "ok"
+    And the m6 smoke response data "status" should equal "applied"
+
+  # --- A2A facade registry and context operations ---
+
+  Scenario: M6 smoke A2A registry list tools returns empty list
+    When I m6 smoke dispatch "registry.list_tools" with params {}
+    Then the m6 smoke response status should be "ok"
+    And the m6 smoke response data should contain key "tools"
+
+  Scenario: M6 smoke A2A registry list resources returns empty list
+    When I m6 smoke dispatch "registry.list_resources" with params {}
+    Then the m6 smoke response status should be "ok"
+    And the m6 smoke response data should contain key "resources"
+
+  Scenario: M6 smoke A2A context get returns context dict
+    When I m6 smoke dispatch "context.get" with params {}
+    Then the m6 smoke response status should be "ok"
+    And the m6 smoke response data should contain key "context"
+
+  Scenario: M6 smoke A2A event subscribe returns subscription id
+    When I m6 smoke dispatch "event.subscribe" with params {}
+    Then the m6 smoke response status should be "ok"
+    And the m6 smoke response data should contain key "subscription_id"
+
+  # --- A2A facade error handling ---
+
+  Scenario: M6 smoke A2A unknown operation raises error
+    When I m6 smoke dispatch unknown operation "nonexistent.op"
+    Then the m6 smoke facade should raise A2aOperationNotFoundError
+
+  Scenario: M6 smoke A2A dispatch with invalid request type raises TypeError
+    When I m6 smoke dispatch with a non-A2aRequest object
+    Then the m6 smoke facade should raise TypeError
+
+  # --- A2A facade service registration ---
+
+  Scenario: M6 smoke A2A register service stores service
+    When I m6 smoke register service "plan_service" on the facade
+    Then the m6 smoke facade should have service "plan_service"
+
+  Scenario: M6 smoke A2A list operations returns all supported
+    When I m6 smoke list facade operations
+    Then the m6 smoke operations should include "session.create"
+    And the m6 smoke operations should include "plan.execute"
+    And the m6 smoke operations should include "event.subscribe"
+    And the m6 smoke operations count should be 42
+
+  # --- A2A event queue (AC-2: event queue publish/subscribe) ---
+
+  Scenario: M6 smoke A2A event queue publish and retrieve
+    Given a m6 smoke A2A event queue
+    When I m6 smoke publish an event with type "plan.progress"
+    Then the m6 smoke event queue should have 1 event
+    And the m6 smoke last event type should be "plan.progress"
+
+  Scenario: M6 smoke A2A event queue subscribe local callback
+    Given a m6 smoke A2A event queue
+    When I m6 smoke subscribe a local callback
+    And I m6 smoke publish an event with type "plan.complete"
+    Then the m6 smoke callback should have been called once
+
+  Scenario: M6 smoke A2A event queue unsubscribe
+    Given a m6 smoke A2A event queue
+    When I m6 smoke subscribe a local callback
+    And I m6 smoke unsubscribe the callback
+    And I m6 smoke publish an event with type "plan.complete"
+    Then the m6 smoke callback should not have been called
+
+  Scenario: M6 smoke A2A event queue close prevents publish
+    Given a m6 smoke A2A event queue
+    When I m6 smoke close the event queue
+    Then the m6 smoke publishing should raise RuntimeError
+
+  Scenario: M6 smoke A2A event queue remote subscribe raises error
+    Given a m6 smoke A2A event queue
+    When I m6 smoke attempt remote subscribe to "https://example.com/events"
+    Then the m6 smoke facade should raise A2aNotAvailableError
+
+  # --- A2A HTTP transport stub ---
+
+  Scenario: M6 smoke A2A transport send raises not available
+    When I m6 smoke attempt transport send
+    Then the m6 smoke facade should raise A2aNotAvailableError
+
+  Scenario: M6 smoke A2A transport connect raises not available
+    When I m6 smoke attempt transport connect to "https://example.com/a2a"
+    Then the m6 smoke facade should raise A2aNotAvailableError
+
+  Scenario: M6 smoke A2A transport disconnect raises not available
+    When I m6 smoke attempt transport disconnect
+    Then the m6 smoke facade should raise A2aNotAvailableError
+
+  Scenario: M6 smoke A2A transport is_connected returns false
+    When I m6 smoke check transport is_connected
+    Then the m6 smoke transport should not be connected
+
+  # --- A2A version negotiation ---
+
+  Scenario: M6 smoke A2A version negotiation accepts 1.0
+    When I m6 smoke negotiate A2A version "1.0"
+    Then the m6 smoke negotiated version should be "1.0"
+
+  Scenario: M6 smoke A2A version negotiation rejects unsupported
+    When I m6 smoke negotiate A2A version "2.0"
+    Then the m6 smoke facade should raise A2aVersionMismatchError
+
+  Scenario: M6 smoke A2A version is_supported returns correct result
+    When I m6 smoke check if version "1.0" is supported
+    Then the m6 smoke version support should be true
+    When I m6 smoke check if version "99.0" is supported
+    Then the m6 smoke version support should be false
+
+  # --- Automation profiles built-in (AC-4: profile resolution) ---
+
+  Scenario: M6 smoke all 8 built-in profiles exist
+    When I m6 smoke list all built-in profiles
+    Then the m6 smoke profile count should be 8
+    And the m6 smoke profiles should include "manual"
+    And the m6 smoke profiles should include "full-auto"
+
+  Scenario: M6 smoke manual profile has all thresholds at 1.0
+    When I m6 smoke load built-in profile "manual"
+    Then the m6 smoke profile decompose_task should be 1.0
+    And the m6 smoke profile create_tool should be 1.0
+    And the m6 smoke profile select_tool should be 1.0
+    And the m6 smoke profile require_sandbox should be true
+
+  Scenario: M6 smoke full-auto profile has no gates
+    When I m6 smoke load built-in profile "full-auto"
+    Then the m6 smoke profile decompose_task should be 0.0
+    And the m6 smoke profile create_tool should be 0.0
+    And the m6 smoke profile select_tool should be 0.0
+    And the m6 smoke profile require_sandbox should be false
+    And the m6 smoke profile allow_unsafe_tools should be true
+
+  # --- Automation profile creation and validation ---
+
+  Scenario: M6 smoke create custom namespaced profile
+    When I m6 smoke create a profile named "acme/strict" with select_tool 1.0
+    Then the m6 smoke created profile name should be "acme/strict"
+    And the m6 smoke created profile select_tool should be 1.0
+
+  Scenario: M6 smoke profile name validation rejects invalid
+    When I m6 smoke create a profile with invalid name "has spaces"
+    Then the m6 smoke creation should raise ValueError
+
+  Scenario: M6 smoke profile threshold validation rejects out of range
+    When I m6 smoke create a profile with decompose_task 1.5
+    Then the m6 smoke creation should raise ValueError
+
+  Scenario: M6 smoke profile from_yaml loads correctly
+    Given a m6 smoke temporary profile YAML file
+    When I m6 smoke load profile from the temp YAML
+    Then the m6 smoke loaded profile name should be "test-yaml-profile"
+
+  # --- Guard enforcement (AC-3: denylist, budget caps, tool call limits) ---
+
+  Scenario: M6 smoke guard denylist blocks denied tool
+    Given a m6 smoke profile with denylist guard for "rm_rf"
+    When I m6 smoke check guard for tool "rm_rf"
+    Then the m6 smoke guard result should not be allowed
+    And the m6 smoke guard reason should contain "denylist"
+
+  Scenario: M6 smoke guard denylist allows non-denied tool
+    Given a m6 smoke profile with denylist guard for "rm_rf"
+    When I m6 smoke check guard for tool "read_file"
+    Then the m6 smoke guard result should be allowed
+
+  Scenario: M6 smoke guard allowlist blocks unlisted tool
+    Given a m6 smoke profile with allowlist guard for "read_file" and "search"
+    When I m6 smoke check guard for tool "write_file"
+    Then the m6 smoke guard result should not be allowed
+    And the m6 smoke guard reason should contain "allowlist"
+
+  Scenario: M6 smoke guard max tool calls blocks at limit
+    Given a m6 smoke profile with max 5 tool calls per step
+    When I m6 smoke check guard for tool "llm_call" with 5 calls so far
+    Then the m6 smoke guard result should not be allowed
+    And the m6 smoke guard reason should contain "limit"
+
+  Scenario: M6 smoke guard cost budget blocks at cap
+    Given a m6 smoke profile with max cost 10.0
+    When I m6 smoke check guard for tool "llm_call" with cost 10.0
+    Then the m6 smoke guard result should not be allowed
+    And the m6 smoke guard reason should contain "budget"
+
+  Scenario: M6 smoke guard write approval blocks write operations
+    Given a m6 smoke profile with write approval required
+    When I m6 smoke check guard for tool "write_file" as a write operation
+    Then the m6 smoke guard result should not be allowed
+    And the m6 smoke guard reason should contain "Write operations"
+
+  Scenario: M6 smoke guard apply approval blocks apply phase
+    Given a m6 smoke profile with apply approval required
+    When I m6 smoke check guard for tool "__apply__"
+    Then the m6 smoke guard result should not be allowed
+    And the m6 smoke guard reason should contain "Apply phase"
+
+  Scenario: M6 smoke guard with no guards allows everything
+    Given a m6 smoke profile with no guards
+    When I m6 smoke check guard for tool "anything"
+    Then the m6 smoke guard result should be allowed
+
+  # --- Profile service resolution precedence (AC-4: plan > action > global) ---
+
+  Scenario: M6 smoke profile resolution plan takes precedence
+    Given a m6 smoke automation profile service
+    When I m6 smoke resolve profile with plan "ci" action "auto" project "manual"
+    Then the m6 smoke resolved profile name should be "ci"
+
+  Scenario: M6 smoke profile resolution action takes precedence over project
+    Given a m6 smoke automation profile service
+    When I m6 smoke resolve profile with plan null action "auto" project "manual"
+    Then the m6 smoke resolved profile name should be "auto"
+
+  Scenario: M6 smoke profile resolution falls back to global default
+    Given a m6 smoke automation profile service
+    When I m6 smoke resolve profile with plan null action null project null
+    Then the m6 smoke resolved profile name should be "manual"
+
+  # --- Profile service guard evaluation ---
+
+  Scenario: M6 smoke service evaluate guard delegates to profile
+    Given a m6 smoke automation profile service
+    When I m6 smoke evaluate guard for profile "manual" and tool "read_file"
+    Then the m6 smoke guard result should be allowed
+
+  # --- A2A model validation ---
+
+  Scenario: M6 smoke A2aRequest validates non-empty operation
+    When I m6 smoke create A2aRequest with empty operation
+    Then the m6 smoke creation should raise ValueError
+
+  Scenario: M6 smoke A2aResponse validates status values
+    When I m6 smoke create A2aResponse with invalid status "maybe"
+    Then the m6 smoke creation should raise ValueError
+
+  Scenario: M6 smoke A2aEvent validates non-empty event_type
+    When I m6 smoke create A2aEvent with empty event_type
+    Then the m6 smoke creation should raise ValueError
+
+  Scenario: M6 smoke A2aErrorDetail validates non-empty fields
+    When I m6 smoke create A2aErrorDetail with empty code
+    Then the m6 smoke creation should raise ValueError