v2.6.2 (#526)

Co-authored-by: Mistral Vibe <vibe@mistral.ai>

.vscode/launch.json

@@ -1,5 +1,5 @@
 {
-  "version": "2.6.1",
+  "version": "2.6.2",
   "configurations": [
     {
       "name": "ACP Server",

CHANGELOG.md

@@ -5,6 +5,17 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [2.6.2] - 2026-03-23
+
+### Changed
+
+- Pinned agent-client-protocol dependency back to 0.8.1
+
+### Removed
+
+- Context usage updates via ACP
+
+
 ## [2.6.1] - 2026-03-23
 
 ### Changed

distribution/zed/extension.toml

@@ -1,7 +1,7 @@
 id = "mistral-vibe"
 name = "Mistral Vibe"
 description = "Mistral's open-source coding assistant"
-version = "2.6.1"
+version = "2.6.2"
 schema_version = 1
 authors = ["Mistral AI"]
 repository = "https://github.com/mistralai/mistral-vibe"
@@ -11,25 +11,25 @@ name = "Mistral Vibe"
 icon = "./icons/mistral_vibe.svg"
 
 [agent_servers.mistral-vibe.targets.darwin-aarch64]
-archive = "https://github.com/mistralai/mistral-vibe/releases/download/v2.6.1/vibe-acp-darwin-aarch64-2.6.1.zip"
+archive = "https://github.com/mistralai/mistral-vibe/releases/download/v2.6.2/vibe-acp-darwin-aarch64-2.6.2.zip"
 cmd = "./vibe-acp"
 
 [agent_servers.mistral-vibe.targets.darwin-x86_64]
-archive = "https://github.com/mistralai/mistral-vibe/releases/download/v2.6.1/vibe-acp-darwin-x86_64-2.6.1.zip"
+archive = "https://github.com/mistralai/mistral-vibe/releases/download/v2.6.2/vibe-acp-darwin-x86_64-2.6.2.zip"
 cmd = "./vibe-acp"
 
 [agent_servers.mistral-vibe.targets.linux-aarch64]
-archive = "https://github.com/mistralai/mistral-vibe/releases/download/v2.6.1/vibe-acp-linux-aarch64-2.6.1.zip"
+archive = "https://github.com/mistralai/mistral-vibe/releases/download/v2.6.2/vibe-acp-linux-aarch64-2.6.2.zip"
 cmd = "./vibe-acp"
 
 [agent_servers.mistral-vibe.targets.linux-x86_64]
-archive = "https://github.com/mistralai/mistral-vibe/releases/download/v2.6.1/vibe-acp-linux-x86_64-2.6.1.zip"
+archive = "https://github.com/mistralai/mistral-vibe/releases/download/v2.6.2/vibe-acp-linux-x86_64-2.6.2.zip"
 cmd = "./vibe-acp"
 
 [agent_servers.mistral-vibe.targets.windows-aarch64]
-archive = "https://github.com/mistralai/mistral-vibe/releases/download/v2.6.1/vibe-acp-windows-aarch64-2.6.1.zip"
+archive = "https://github.com/mistralai/mistral-vibe/releases/download/v2.6.2/vibe-acp-windows-aarch64-2.6.2.zip"
 cmd = "./vibe-acp.exe"
 
 [agent_servers.mistral-vibe.targets.windows-x86_64]
-archive = "https://github.com/mistralai/mistral-vibe/releases/download/v2.6.1/vibe-acp-windows-x86_64-2.6.1.zip"
+archive = "https://github.com/mistralai/mistral-vibe/releases/download/v2.6.2/vibe-acp-windows-x86_64-2.6.2.zip"
 cmd = "./vibe-acp.exe"

pyproject.toml

@@ -1,6 +1,6 @@
 [project]
 name = "mistral-vibe"
-version = "2.6.1"
+version = "2.6.2"
 description = "Minimal CLI coding agent by Mistral"
 readme = "README.md"
 requires-python = ">=3.12"
@@ -27,7 +27,7 @@ classifiers = [
     "Topic :: Utilities",
 ]
 dependencies = [
-    "agent-client-protocol>=0.9.0a1",
+    "agent-client-protocol==0.8.1",
     "anyio>=4.12.0",
     "cachetools>=5.5.0",
     "cryptography>=44.0.0,<=46.0.3",
@@ -113,7 +113,6 @@ build = ["pyinstaller>=6.17.0", "truststore>=0.10.4"]
 pythonVersion = "3.12"
 reportMissingTypeStubs = false
 reportPrivateImportUsage = false
-
 include = ["vibe/**/*.py", "tests/**/*.py"]
 exclude = ["pyinstaller/"]
 venvPath = "."

tests/acp/test_initialize.py

@@ -28,7 +28,7 @@ class TestACPInitialize:
             session_capabilities=SessionCapabilities(list=SessionListCapabilities()),
         )
         assert response.agent_info == Implementation(
-            name="@mistralai/mistral-vibe", title="Mistral Vibe", version="2.6.1"
+            name="@mistralai/mistral-vibe", title="Mistral Vibe", version="2.6.2"
         )
 
         assert response.auth_methods == []
@@ -52,7 +52,7 @@ class TestACPInitialize:
             session_capabilities=SessionCapabilities(list=SessionListCapabilities()),
         )
         assert response.agent_info == Implementation(
-            name="@mistralai/mistral-vibe", title="Mistral Vibe", version="2.6.1"
+            name="@mistralai/mistral-vibe", title="Mistral Vibe", version="2.6.2"
         )
 
         assert response.auth_methods is not None

tests/acp/test_load_session.py

@@ -100,11 +100,13 @@ class TestLoadSession:
 
         assert response.config_options is not None
         assert len(response.config_options) == 2
-        assert response.config_options[0].id == "mode"
+        assert response.config_options[0].root.id == "mode"
-        assert response.config_options[0].category == "mode"
+        assert response.config_options[0].root.category == "mode"
-        assert response.config_options[0].current_value == BuiltinAgentName.DEFAULT
+        assert response.config_options[0].root.current_value == BuiltinAgentName.DEFAULT
-        assert len(response.config_options[0].options) == 5
+        assert len(response.config_options[0].root.options) == 5
-        mode_option_values = {opt.value for opt in response.config_options[0].options}
+        mode_option_values = {
+            opt.value for opt in response.config_options[0].root.options
+        }
         assert mode_option_values == {
             BuiltinAgentName.DEFAULT,
             BuiltinAgentName.CHAT,
@@ -112,11 +114,13 @@ class TestLoadSession:
             BuiltinAgentName.PLAN,
             BuiltinAgentName.ACCEPT_EDITS,
         }
-        assert response.config_options[1].id == "model"
+        assert response.config_options[1].root.id == "model"
-        assert response.config_options[1].category == "model"
+        assert response.config_options[1].root.category == "model"
-        assert response.config_options[1].current_value == "devstral-latest"
+        assert response.config_options[1].root.current_value == "devstral-latest"
-        assert len(response.config_options[1].options) == 2
+        assert len(response.config_options[1].root.options) == 2
-        model_option_values = {opt.value for opt in response.config_options[1].options}
+        model_option_values = {
+            opt.value for opt in response.config_options[1].root.options
+        }
         assert model_option_values == {"devstral-latest", "devstral-small"}
 
     @pytest.mark.asyncio

tests/acp/test_new_session.py

@@ -103,11 +103,11 @@ class TestACPNewSession:
 
         # Mode config option
         mode_config = session_response.config_options[0]
-        assert mode_config.id == "mode"
+        assert mode_config.root.id == "mode"
-        assert mode_config.category == "mode"
+        assert mode_config.root.category == "mode"
-        assert mode_config.current_value == BuiltinAgentName.DEFAULT
+        assert mode_config.root.current_value == BuiltinAgentName.DEFAULT
-        assert len(mode_config.options) == 5
+        assert len(mode_config.root.options) == 5
-        mode_option_values = {opt.value for opt in mode_config.options}
+        mode_option_values = {opt.value for opt in mode_config.root.options}
         assert mode_option_values == {
             BuiltinAgentName.DEFAULT,
             BuiltinAgentName.CHAT,
@@ -118,11 +118,11 @@ class TestACPNewSession:
 
         # Model config option
         model_config = session_response.config_options[1]
-        assert model_config.id == "model"
+        assert model_config.root.id == "model"
-        assert model_config.category == "model"
+        assert model_config.root.category == "model"
-        assert model_config.current_value == "devstral-latest"
+        assert model_config.root.current_value == "devstral-latest"
-        assert len(model_config.options) == 2
+        assert len(model_config.root.options) == 2
-        model_option_values = {opt.value for opt in model_config.options}
+        model_option_values = {opt.value for opt in model_config.root.options}
         assert model_option_values == {"devstral-latest", "devstral-small"}
 
     @pytest.mark.skip(reason="TODO: Fix this test")

tests/acp/test_set_config_option.py

@@ -83,8 +83,8 @@ class TestACPSetConfigOptionMode:
 
         # Verify config_options reflect the new state
         mode_config = response.config_options[0]
-        assert mode_config.id == "mode"
+        assert mode_config.root.id == "mode"
-        assert mode_config.current_value == BuiltinAgentName.AUTO_APPROVE
+        assert mode_config.root.current_value == BuiltinAgentName.AUTO_APPROVE
 
     @pytest.mark.asyncio
     async def test_set_config_option_mode_to_plan(
@@ -133,8 +133,8 @@ class TestACPSetConfigOptionMode:
         )  # Chat mode auto-approves read-only tools
 
         mode_config = response.config_options[0]
-        assert mode_config.id == "mode"
+        assert mode_config.root.id == "mode"
-        assert mode_config.current_value == BuiltinAgentName.CHAT
+        assert mode_config.root.current_value == BuiltinAgentName.CHAT
 
     @pytest.mark.asyncio
     async def test_set_config_option_mode_invalid_returns_none(
@@ -205,8 +205,8 @@ class TestACPSetConfigOptionModel:
 
         # Verify config_options reflect the new state
         model_config = response.config_options[1]
-        assert model_config.id == "model"
+        assert model_config.root.id == "model"
-        assert model_config.current_value == "devstral-small"
+        assert model_config.root.current_value == "devstral-small"
 
     @pytest.mark.asyncio
     async def test_set_config_option_model_invalid_returns_none(

tests/acp/test_usage_update.py

@@ -1,254 +0,0 @@
-from __future__ import annotations
-
-import asyncio
-import json
-from pathlib import Path
-from unittest.mock import patch
-
-from acp.schema import TextContentBlock, UsageUpdate
-import pytest
-
-from tests.acp.conftest import _create_acp_agent
-from tests.conftest import build_test_vibe_config
-from tests.stubs.fake_backend import FakeBackend
-from tests.stubs.fake_client import FakeClient
-from vibe.acp.acp_agent_loop import VibeAcpAgentLoop
-from vibe.core.agent_loop import AgentLoop
-from vibe.core.config import SessionLoggingConfig
-from vibe.core.types import LLMChunk, LLMMessage, LLMUsage, Role
-
-
-def _make_backend(prompt_tokens: int = 100, completion_tokens: int = 50) -> FakeBackend:
-    return FakeBackend(
-        LLMChunk(
-            message=LLMMessage(role=Role.assistant, content="Hi"),
-            usage=LLMUsage(
-                prompt_tokens=prompt_tokens, completion_tokens=completion_tokens
-            ),
-        )
-    )
-
-
-def _make_acp_agent(backend: FakeBackend) -> VibeAcpAgentLoop:
-    config = build_test_vibe_config()
-
-    class PatchedAgentLoop(AgentLoop):
-        def __init__(self, *args, **kwargs) -> None:
-            super().__init__(*args, **{**kwargs, "backend": backend})
-            self._base_config = config
-            self.agent_manager.invalidate_config()
-
-    patch("vibe.acp.acp_agent_loop.AgentLoop", side_effect=PatchedAgentLoop).start()
-    return _create_acp_agent()
-
-
-def _get_fake_client(agent: VibeAcpAgentLoop) -> FakeClient:
-    return agent.client  # type: ignore[return-value]
-
-
-def _get_usage_updates(client: FakeClient) -> list[UsageUpdate]:
-    return [
-        update.update
-        for update in client._session_updates
-        if isinstance(update.update, UsageUpdate)
-    ]
-
-
-class TestPromptResponseUsage:
-    @pytest.mark.asyncio
-    async def test_prompt_returns_usage_in_response(self) -> None:
-        agent = _make_acp_agent(_make_backend(prompt_tokens=100, completion_tokens=50))
-        session = await agent.new_session(cwd=str(Path.cwd()), mcp_servers=[])
-
-        response = await agent.prompt(
-            session_id=session.session_id,
-            prompt=[TextContentBlock(type="text", text="Hello")],
-        )
-
-        assert response.usage is not None
-        assert response.usage.input_tokens == 100
-        assert response.usage.output_tokens == 50
-        assert response.usage.total_tokens == 150
-
-    @pytest.mark.asyncio
-    async def test_prompt_usage_optional_fields_are_none(self) -> None:
-        agent = _make_acp_agent(_make_backend())
-        session = await agent.new_session(cwd=str(Path.cwd()), mcp_servers=[])
-
-        response = await agent.prompt(
-            session_id=session.session_id,
-            prompt=[TextContentBlock(type="text", text="Hello")],
-        )
-
-        assert response.usage is not None
-        assert response.usage.thought_tokens is None
-        assert response.usage.cached_read_tokens is None
-        assert response.usage.cached_write_tokens is None
-
-    @pytest.mark.asyncio
-    async def test_prompt_usage_accumulates_across_turns(self) -> None:
-        backend = _make_backend(prompt_tokens=100, completion_tokens=50)
-        agent = _make_acp_agent(backend)
-        session = await agent.new_session(cwd=str(Path.cwd()), mcp_servers=[])
-
-        first = await agent.prompt(
-            session_id=session.session_id,
-            prompt=[TextContentBlock(type="text", text="Hello")],
-        )
-
-        second = await agent.prompt(
-            session_id=session.session_id,
-            prompt=[TextContentBlock(type="text", text="Hello again")],
-        )
-
-        assert first.usage is not None
-        assert second.usage is not None
-        # Second turn should have strictly more cumulative tokens
-        assert second.usage.input_tokens > first.usage.input_tokens
-        assert second.usage.output_tokens > first.usage.output_tokens
-        assert second.usage.total_tokens > first.usage.total_tokens
-
-
-class TestUsageUpdateNotification:
-    @pytest.mark.asyncio
-    async def test_prompt_sends_usage_update(self) -> None:
-        agent = _make_acp_agent(_make_backend())
-        session = await agent.new_session(cwd=str(Path.cwd()), mcp_servers=[])
-
-        await agent.prompt(
-            session_id=session.session_id,
-            prompt=[TextContentBlock(type="text", text="Hello")],
-        )
-        await asyncio.sleep(0)
-
-        usage_updates = _get_usage_updates(_get_fake_client(agent))
-        assert len(usage_updates) == 1
-        assert usage_updates[0].session_update == "usage_update"
-
-    @pytest.mark.asyncio
-    async def test_usage_update_contains_context_window_info(self) -> None:
-        agent = _make_acp_agent(_make_backend(prompt_tokens=100, completion_tokens=50))
-        session = await agent.new_session(cwd=str(Path.cwd()), mcp_servers=[])
-
-        await agent.prompt(
-            session_id=session.session_id,
-            prompt=[TextContentBlock(type="text", text="Hello")],
-        )
-        await asyncio.sleep(0)
-
-        usage_updates = _get_usage_updates(_get_fake_client(agent))
-        assert len(usage_updates) == 1
-        assert usage_updates[0].size > 0
-        assert usage_updates[0].used > 0
-
-    @pytest.mark.asyncio
-    async def test_usage_update_contains_cost_when_pricing_set(self) -> None:
-        agent = _make_acp_agent(
-            _make_backend(prompt_tokens=1_000_000, completion_tokens=500_000)
-        )
-        session = await agent.new_session(cwd=str(Path.cwd()), mcp_servers=[])
-
-        # Set pricing directly on the session stats (config loading uses fixture defaults)
-        acp_session = agent.sessions[session.session_id]
-        acp_session.agent_loop.stats.update_pricing(input_price=0.4, output_price=2.0)
-
-        await agent.prompt(
-            session_id=session.session_id,
-            prompt=[TextContentBlock(type="text", text="Hello")],
-        )
-        await asyncio.sleep(0)
-
-        usage_updates = _get_usage_updates(_get_fake_client(agent))
-        assert len(usage_updates) == 1
-        cost = usage_updates[0].cost
-        assert cost is not None
-        assert cost.currency == "USD"
-        assert cost.amount > 0
-
-    @pytest.mark.asyncio
-    async def test_usage_update_no_cost_when_zero_pricing(self) -> None:
-        agent = _make_acp_agent(_make_backend())
-        session = await agent.new_session(cwd=str(Path.cwd()), mcp_servers=[])
-
-        await agent.prompt(
-            session_id=session.session_id,
-            prompt=[TextContentBlock(type="text", text="Hello")],
-        )
-        await asyncio.sleep(0)
-
-        usage_updates = _get_usage_updates(_get_fake_client(agent))
-        assert len(usage_updates) == 1
-        assert usage_updates[0].cost is None
-
-    @pytest.mark.asyncio
-    async def test_usage_update_sent_per_prompt(self) -> None:
-        backend = _make_backend()
-        agent = _make_acp_agent(backend)
-        session = await agent.new_session(cwd=str(Path.cwd()), mcp_servers=[])
-
-        await agent.prompt(
-            session_id=session.session_id,
-            prompt=[TextContentBlock(type="text", text="Hello")],
-        )
-        await asyncio.sleep(0)
-        await agent.prompt(
-            session_id=session.session_id,
-            prompt=[TextContentBlock(type="text", text="Hello again")],
-        )
-        await asyncio.sleep(0)
-
-        usage_updates = _get_usage_updates(_get_fake_client(agent))
-        assert len(usage_updates) == 2
-
-
-class TestLoadSessionUsageUpdate:
-    def _make_session_dir(self, tmp_path: Path, session_id: str, cwd: str) -> Path:
-        session_folder = tmp_path / f"session_20240101_120000_{session_id[:8]}"
-        session_folder.mkdir()
-        messages_file = session_folder / "messages.jsonl"
-        with messages_file.open("w") as f:
-            f.write(json.dumps({"role": "user", "content": "Hello"}) + "\n")
-        meta = {
-            "session_id": session_id,
-            "start_time": "2024-01-01T12:00:00Z",
-            "end_time": "2024-01-01T12:05:00Z",
-            "environment": {"working_directory": cwd},
-        }
-        with (session_folder / "meta.json").open("w") as f:
-            json.dump(meta, f)
-        return session_folder
-
-    def _make_agent_with_session_logging(
-        self, backend: FakeBackend, session_dir: Path
-    ) -> VibeAcpAgentLoop:
-        session_config = SessionLoggingConfig(
-            save_dir=str(session_dir), session_prefix="session", enabled=True
-        )
-        config = build_test_vibe_config(session_logging=session_config)
-
-        class PatchedAgentLoop(AgentLoop):
-            def __init__(self, *args, **kwargs) -> None:
-                super().__init__(*args, **{**kwargs, "backend": backend})
-                self._base_config = config
-                self.agent_manager.invalidate_config()
-
-        patch("vibe.acp.acp_agent_loop.AgentLoop", side_effect=PatchedAgentLoop).start()
-        agent = _create_acp_agent()
-        patch.object(agent, "_load_config", return_value=config).start()
-        return agent
-
-    @pytest.mark.asyncio
-    async def test_load_session_sends_usage_update(self, tmp_path: Path) -> None:
-        backend = _make_backend()
-        agent = self._make_agent_with_session_logging(backend, tmp_path)
-        session_id = "test-session-load-usage"
-        self._make_session_dir(tmp_path, session_id, str(Path.cwd()))
-
-        await agent.load_session(cwd=str(Path.cwd()), session_id=session_id)
-        await asyncio.sleep(0)
-
-        client = _get_fake_client(agent)
-        usage_updates = _get_usage_updates(client)
-        assert len(usage_updates) == 1
-        assert usage_updates[0].session_update == "usage_update"
-        assert usage_updates[0].size > 0

tests/stubs/fake_client.py

@@ -6,7 +6,7 @@ from acp import (
     Agent as AcpAgent,
     Client,
     CreateTerminalResponse,
-    KillTerminalResponse,
+    KillTerminalCommandResponse,
     ReadTextFileResponse,
     ReleaseTerminalResponse,
     RequestPermissionResponse,
@@ -112,7 +112,7 @@ class FakeClient(Client):
 
     async def kill_terminal(
         self, session_id: str, terminal_id: str, **kwargs: Any
-    ) -> KillTerminalResponse | None:
+    ) -> KillTerminalCommandResponse | None:
         raise NotImplementedError()
 
     async def ext_method(self, method: str, params: dict[str, Any]) -> dict[str, Any]:

uv.lock

@@ -4,14 +4,14 @@ requires-python = ">=3.12"
 
 [[package]]
 name = "agent-client-protocol"
-version = "0.9.0a1"
+version = "0.8.1"
 source = { registry = "https://pypi.org/simple" }
 dependencies = [
     { name = "pydantic" },
 ]
-sdist = { url = "https://files.pythonhosted.org/packages/1b/dc/1ec56897b461fbdb844c9bff3abbbe225bfe8cda020dc2449101a6d76592/agent_client_protocol-0.9.0a1.tar.gz", hash = "sha256:9e6fc8b72df465279470920d679c871e0c658f69212e345563cc69b17906b606", size = 70423, upload-time = "2026-03-19T18:44:47.117Z" }
+sdist = { url = "https://files.pythonhosted.org/packages/1b/7b/7cdac86db388809d9e3bc58cac88cc7dfa49b7615b98fab304a828cd7f8a/agent_client_protocol-0.8.1.tar.gz", hash = "sha256:1bbf15663bf51f64942597f638e32a6284c5da918055d9672d3510e965143dbd", size = 68866, upload-time = "2026-02-13T15:34:54.567Z" }
 wheels = [
-    { url = "https://files.pythonhosted.org/packages/cd/59/b794d5247aac2693a562ddd6eb2092581331496815967a6bca6bbf086b4f/agent_client_protocol-0.9.0a1-py3-none-any.whl", hash = "sha256:3e0962df15c3c7dd2957daea2f47db5e644fd897e77180e492f0a27d9fdb7bf4", size = 55945, upload-time = "2026-03-19T18:44:45.924Z" },
+    { url = "https://files.pythonhosted.org/packages/4b/f3/219eeca0ad4a20843d4b9eaac5532f87018b9d25730a62a16f54f6c52d1a/agent_client_protocol-0.8.1-py3-none-any.whl", hash = "sha256:9421a11fd435b4831660272d169c3812d553bb7247049c138c3ca127e4b8af8e", size = 54529, upload-time = "2026-02-13T15:34:53.344Z" },
 ]
 
 [[package]]
@@ -770,7 +770,7 @@ wheels = [
 
 [[package]]
 name = "mistral-vibe"
-version = "2.6.1"
+version = "2.6.2"
 source = { editable = "." }
 dependencies = [
     { name = "agent-client-protocol" },
@@ -832,7 +832,7 @@ dev = [
 
 [package.metadata]
 requires-dist = [
-    { name = "agent-client-protocol", specifier = ">=0.9.0a1" },
+    { name = "agent-client-protocol", specifier = "==0.8.1" },
     { name = "anyio", specifier = ">=4.12.0" },
     { name = "cachetools", specifier = ">=5.5.0" },
     { name = "cryptography", specifier = ">=44.0.0,<=46.0.3" },

vibe/__init__.py

@@ -3,4 +3,4 @@ from __future__ import annotations
 from pathlib import Path
 
 VIBE_ROOT = Path(__file__).parent
-__version__ = "2.6.1"
+__version__ = "2.6.2"

vibe/acp/acp_agent_loop.py

@@ -26,14 +26,11 @@ from acp.schema import (
     AgentThoughtChunk,
     AllowedOutcome,
     AuthenticateResponse,
-    AuthMethodAgent,
+    AuthMethod,
     AvailableCommand,
     AvailableCommandInput,
     ClientCapabilities,
-    CloseSessionResponse,
     ContentToolCallContent,
-    Cost,
-    EnvVarAuthMethod,
     ForkSessionResponse,
     HttpMcpServer,
     Implementation,
@@ -46,14 +43,11 @@ from acp.schema import (
     SessionListCapabilities,
     SetSessionConfigOptionResponse,
     SseMcpServer,
-    TerminalAuthMethod,
     TextContentBlock,
     TextResourceContents,
     ToolCallProgress,
     ToolCallUpdate,
     UnstructuredCommandInput,
-    Usage,
-    UsageUpdate,
     UserMessageChunk,
 )
 from pydantic import BaseModel, ConfigDict
@@ -180,10 +174,9 @@ class VibeAcpAgentLoop(AcpAgent):
             and self.client_capabilities.field_meta.get("terminal-auth") is True
         )
 
-        auth_methods: list[EnvVarAuthMethod | TerminalAuthMethod | AuthMethodAgent] = (
+        auth_methods = (
             [
-                TerminalAuthMethod(
+                AuthMethod(
-                    type="terminal",
                     id="vibe-setup",
                     name="Register your API Key",
                     description="Register your API Key inside Mistral Vibe",
@@ -387,39 +380,6 @@ class VibeAcpAgentLoop(AcpAgent):
             raise SessionNotFoundError(session_id)
         return self.sessions[session_id]
 
-    def _build_usage(self, session: AcpSessionLoop) -> Usage:
-        stats = session.agent_loop.stats
-        return Usage(
-            input_tokens=stats.session_prompt_tokens,
-            output_tokens=stats.session_completion_tokens,
-            total_tokens=stats.session_total_llm_tokens,
-        )
-
-    def _build_usage_update(self, session: AcpSessionLoop) -> UsageUpdate:
-        stats = session.agent_loop.stats
-        active_model = session.agent_loop.config.get_active_model()
-        cost = (
-            Cost(amount=stats.session_cost, currency="USD")
-            if stats.input_price_per_million > 0 or stats.output_price_per_million > 0
-            else None
-        )
-        return UsageUpdate(
-            session_update="usage_update",
-            used=stats.context_tokens,
-            size=active_model.auto_compact_threshold,
-            cost=cost,
-        )
-
-    def _send_usage_update(self, session: AcpSessionLoop) -> None:
-        async def _send() -> None:
-            try:
-                update = self._build_usage_update(session)
-                await self.client.session_update(session_id=session.id, update=update)
-            except Exception:
-                pass
-
-        asyncio.create_task(_send())
-
     async def _replay_tool_calls(self, session_id: str, msg: LLMMessage) -> None:
         if not msg.tool_calls:
             return
@@ -604,7 +564,6 @@ class VibeAcpAgentLoop(AcpAgent):
         session = await self._create_acp_session(session_id, agent_loop)
 
         await self._replay_conversation_history(session_id, non_system_messages)
-        self._send_usage_update(session)
 
         modes_state, modes_config = make_mode_response(
             list(agent_loop.agent_manager.available_agents.values()),
@@ -731,11 +690,7 @@ class VibeAcpAgentLoop(AcpAgent):
 
     @override
     async def prompt(
-        self,
+        self, prompt: list[ContentBlock], session_id: str, **kwargs: Any
-        prompt: list[ContentBlock],
-        session_id: str,
-        message_id: str | None = None,
-        **kwargs: Any,
     ) -> PromptResponse:
         session = self._get_session(session_id)
 
@@ -768,10 +723,7 @@ class VibeAcpAgentLoop(AcpAgent):
             await session.task
 
         except asyncio.CancelledError:
-            self._send_usage_update(session)
+            return PromptResponse(stop_reason="cancelled")
-            return PromptResponse(
-                stop_reason="cancelled", usage=self._build_usage(session)
-            )
 
         except CoreRateLimitError as e:
             raise RateLimitError.from_core(e) from e
@@ -785,8 +737,7 @@ class VibeAcpAgentLoop(AcpAgent):
         finally:
             session.task = None
 
-        self._send_usage_update(session)
+        return PromptResponse(stop_reason="end_turn")
-        return PromptResponse(stop_reason="end_turn", usage=self._build_usage(session))
 
     def _build_text_prompt(self, acp_prompt: list[ContentBlock]) -> str:
         text_prompt = ""
@@ -908,12 +859,6 @@ class VibeAcpAgentLoop(AcpAgent):
             elif isinstance(event, AgentProfileChangedEvent):
                 pass
 
-    @override
-    async def close_session(
-        self, session_id: str, **kwargs: Any
-    ) -> CloseSessionResponse | None:
-        raise NotImplementedMethodError("close_session")
-
     @override
     async def cancel(self, session_id: str, **kwargs: Any) -> None:
         session = self._get_session(session_id)

vibe/acp/utils.py

@@ -9,6 +9,7 @@ from acp.schema import (
     ContentToolCallContent,
     ModelInfo,
     PermissionOption,
+    SessionConfigOption,
     SessionConfigOptionSelect,
     SessionConfigSelectOption,
     SessionMode,
@@ -102,7 +103,7 @@ def is_valid_acp_mode(profiles: list[AgentProfile], mode_name: str) -> bool:
 
 def make_mode_response(
     profiles: list[AgentProfile], current_mode_id: str
-) -> tuple[SessionModeState, SessionConfigOptionSelect]:
+) -> tuple[SessionModeState, SessionConfigOption]:
     session_modes: list[SessionMode] = []
     config_options: list[SessionConfigSelectOption] = []
 
@@ -127,20 +128,22 @@ def make_mode_response(
     state = SessionModeState(
         current_mode_id=current_mode_id, available_modes=session_modes
     )
-    config = SessionConfigOptionSelect(
+    config = SessionConfigOption(
-        id="mode",
+        root=SessionConfigOptionSelect(
-        name="Session Mode",
+            id="mode",
-        current_value=current_mode_id,
+            name="Session Mode",
-        category="mode",
+            current_value=current_mode_id,
-        type="select",
+            category="mode",
-        options=config_options,
+            type="select",
+            options=config_options,
+        )
     )
     return state, config
 
 
 def make_model_response(
     models: list[ModelConfig], current_model_id: str
-) -> tuple[SessionModelState, SessionConfigOptionSelect]:
+) -> tuple[SessionModelState, SessionConfigOption]:
     model_infos: list[ModelInfo] = []
     config_options: list[SessionConfigSelectOption] = []
 
@@ -155,13 +158,15 @@ def make_model_response(
     state = SessionModelState(
         current_model_id=current_model_id, available_models=model_infos
     )
-    config_option = SessionConfigOptionSelect(
+    config_option = SessionConfigOption(
-        id="model",
+        root=SessionConfigOptionSelect(
-        name="Model",
+            id="model",
-        current_value=current_model_id,
+            name="Model",
-        category="model",
+            current_value=current_model_id,
-        type="select",
+            category="model",
-        options=config_options,
+            type="select",
+            options=config_options,
+        )
     )
     return state, config_option