feat: remove fs events so agents are free to read and write files (#141)

- This was motivated by #131 - Claude is not sending the events anymore
- This also reduces the Agentic responsibilities, leaving it to the
agents

Author: carlos-algms

lua/agentic/acp/acp_client.lua

@@ -1,6 +1,5 @@
 local Logger = require("agentic.utils.logger")
 local transport_module = require("agentic.acp.acp_transport")
-local FileSystem = require("agentic.utils.file_system")
 
 --[[
 CRITICAL: Type annotations in this file are essential for Lua Language Server support.
@@ -20,6 +19,7 @@ local KNOWN_ACP_KINDS = {
     fetch = true,
     other = true,
     create = true,
+    write = true,
     switch_mode = true,
 }
 
@@ -70,8 +70,8 @@ function ACPClient:new(config, on_ready)
         },
         capabilities = {
             fs = {
-                readTextFile = true,
-                writeTextFile = true,
+                readTextFile = false,
+                writeTextFile = false,
             },
             terminal = false,
         },
@@ -288,10 +288,10 @@ function ACPClient:_handle_notification(message_id, method, params)
     elseif method == "session/request_permission" then
         --- @diagnostic disable-next-line: param-type-mismatch
         self:__handle_request_permission(message_id, params)
-    elseif method == "fs/read_text_file" then
-        self:_handle_read_text_file(message_id, params)
-    elseif method == "fs/write_text_file" then
-        self:_handle_write_text_file(message_id, params)
+    elseif method == "fs/read_text_file" or method == "fs/write_text_file" then
+        Logger.debug(
+            string.format("Received '%s' notification, ignoring it", method)
+        )
     else
         Logger.notify("Unknown notification method: " .. method)
     end
@@ -460,50 +460,6 @@ function ACPClient:__handle_request_permission(message_id, request)
     end)
 end
 
---- @param message_id number
---- @param params table
-function ACPClient:_handle_read_text_file(message_id, params)
-    local session_id = params.sessionId
-    local path = params.path
-
-    if not session_id or not path then
-        Logger.notify("Received fs/read_text_file without sessionId or path")
-        return
-    end
-
-    self:__with_subscriber(session_id, function()
-        FileSystem.read_file(
-            path,
-            params.line ~= vim.NIL and params.line or nil,
-            params.limit ~= vim.NIL and params.limit or nil,
-            function(content)
-                self:__send_result(message_id, { content = content })
-            end
-        )
-    end)
-end
-
---- @param message_id number
---- @param params table
-function ACPClient:_handle_write_text_file(message_id, params)
-    local session_id = params.sessionId
-    local path = params.path
-    local content = params.content
-
-    if not session_id or not path or not content then
-        Logger.notify(
-            "Received fs/write_text_file without sessionId, path, or content"
-        )
-        return
-    end
-
-    self:__with_subscriber(session_id, function()
-        FileSystem.write_file(path, content, function(error)
-            self:__send_result(message_id, error == nil and vim.NIL or error)
-        end)
-    end)
-end
-
 function ACPClient:stop()
     self.transport:stop()
 end
@@ -760,6 +716,7 @@ return ACPClient
 --- | "SubAgent"
 --- | "other"
 --- | "create"
+--- | "write"
 --- | "Skill"
 --- | "switch_mode"
 

lua/agentic/init.lua

@@ -225,6 +225,17 @@ function Agentic.setup(opts)
 
     Theme.setup()
 
+    -- Force-reload buffers when files change on disk (e.g., agent edits files directly).
+    -- Suppresses the "file changed" prompt so modified buffers reload silently,
+    -- matching Cursor/Zed behavior where agent changes always win.
+    vim.api.nvim_create_autocmd("FileChangedShell", {
+        group = cleanup_group,
+        pattern = "*",
+        callback = function()
+            vim.v.fcs_choice = "reload"
+        end,
+    })
+
     vim.api.nvim_create_autocmd("VimLeavePre", {
         group = cleanup_group,
         callback = function()

lua/agentic/session_manager.lua

@@ -20,6 +20,16 @@ local WidgetLayout = require("agentic.ui.widget_layout")
 --- @class agentic._SessionManagerPrivate
 local P = {}
 
+--- Tool call kinds that mutate files on disk.
+--- When these complete, buffers must be reloaded via checktime.
+local FILE_MUTATING_KINDS = {
+    edit = true,
+    create = true,
+    write = true,
+    delete = true,
+    move = true,
+}
+
 --- Safely invoke a user-configured hook
 --- @param hook_name "on_prompt_submit" | "on_response_complete"
 --- @param data table
@@ -237,6 +247,51 @@ function SessionManager:_on_session_update(update)
     end
 end
 
+--- Handle tool call update: update UI, history, diff preview, permissions, and reload buffers
+--- @param tool_call_update agentic.ui.MessageWriter.ToolCallBase
+function SessionManager:_on_tool_call_update(tool_call_update)
+    self.message_writer:update_tool_call_block(tool_call_update)
+
+    --- @type agentic.ui.ChatHistory.ToolCall
+    local tool_call = {
+        type = "tool_call",
+        tool_call_id = tool_call_update.tool_call_id,
+        status = tool_call_update.status,
+        body = tool_call_update.body,
+        diff = tool_call_update.diff,
+    }
+
+    self.chat_history:update_tool_call(tool_call_update.tool_call_id, tool_call)
+
+    -- pre-emptively clear diff preview when tool call update is received, as it's either done or failed
+    local is_rejection = tool_call_update.status == "failed"
+    self:_clear_diff_in_buffer(tool_call_update.tool_call_id, is_rejection)
+
+    -- Remove the permission request if the tool call failed before user granted it
+    if tool_call_update.status == "failed" then
+        self.permission_manager:remove_request_by_tool_call_id(
+            tool_call_update.tool_call_id
+        )
+    end
+
+    -- Reload buffers when file-mutating tool calls complete
+    if tool_call_update.status == "completed" then
+        local tracker =
+            self.message_writer.tool_call_blocks[tool_call_update.tool_call_id]
+
+        if tracker and tracker.kind and FILE_MUTATING_KINDS[tracker.kind] then
+            vim.cmd.checktime()
+        end
+    end
+
+    if
+        not self.permission_manager.current_request
+        and #self.permission_manager.queue == 0
+    then
+        self.status_animation:start("generating")
+    end
+end
+
 --- Send the newly selected mode to the agent and handle the response
 --- @param mode_id string
 function SessionManager:_handle_mode_change(mode_id)
@@ -549,43 +604,7 @@ function SessionManager:new_session(opts)
         end,
 
         on_tool_call_update = function(tool_call_update)
-            self.message_writer:update_tool_call_block(tool_call_update)
-            --- @type agentic.ui.ChatHistory.ToolCall
-            local tool_call = {
-                type = "tool_call",
-                tool_call_id = tool_call_update.tool_call_id,
-                status = tool_call_update.status,
-                body = tool_call_update.body,
-                diff = tool_call_update.diff,
-            }
-
-            self.chat_history:update_tool_call(
-                tool_call_update.tool_call_id,
-                tool_call
-            )
-
-            -- pre-emptively clear diff preview when tool call update is received, as it's either done or failed
-            local is_rejection = tool_call_update.status == "failed"
-            self:_clear_diff_in_buffer(
-                tool_call_update.tool_call_id,
-                is_rejection
-            )
-
-            -- I need to remove the permission request if the tool call failed before user granted it
-            -- It could happen for many reasons, like invalid parameters, tool not found, etc.
-            -- Mostly comes from the Agent.
-            if tool_call_update.status == "failed" then
-                self.permission_manager:remove_request_by_tool_call_id(
-                    tool_call_update.tool_call_id
-                )
-            end
-
-            if
-                not self.permission_manager.current_request
-                and #self.permission_manager.queue == 0
-            then
-                self.status_animation:start("generating")
-            end
+            self:_on_tool_call_update(tool_call_update)
         end,
 
         on_request_permission = function(request, callback)

lua/agentic/session_manager.test.lua

@@ -340,4 +340,128 @@ describe("agentic.SessionManager", function()
             assert.spy(session.new_session).was.called(1)
         end)
     end)
+
+    describe("FileChangedShell autocommand", function()
+        local Child = require("tests.helpers.child")
+        local child = Child:new()
+
+        before_each(function()
+            child.setup()
+        end)
+
+        after_each(function()
+            child.stop()
+        end)
+
+        it("sets fcs_choice to reload when FileChangedShell fires", function()
+            child.v.fcs_choice = ""
+            child.api.nvim_exec_autocmds("FileChangedShell", {
+                group = "AgenticCleanup",
+                pattern = "*",
+            })
+
+            assert.equal("reload", child.v.fcs_choice)
+        end)
+    end)
+
+    describe("on_tool_call_update: buffer reload", function()
+        --- @type TestStub
+        local checktime_stub
+        --- @type TestStub
+        local schedule_stub
+
+        --- @param tool_call_blocks table<string, table>
+        --- @return agentic.SessionManager
+        local function make_session(tool_call_blocks)
+            return {
+                message_writer = {
+                    update_tool_call_block = function() end,
+                    tool_call_blocks = tool_call_blocks,
+                },
+                permission_manager = {
+                    current_request = nil,
+                    queue = {},
+                    remove_request_by_tool_call_id = function() end,
+                },
+                status_animation = { start = function() end },
+                _clear_diff_in_buffer = function() end,
+                chat_history = { update_tool_call = function() end },
+            } --[[@as agentic.SessionManager]]
+        end
+
+        before_each(function()
+            checktime_stub = spy.stub(vim.cmd, "checktime")
+            schedule_stub = spy.stub(vim, "schedule")
+            schedule_stub:invokes(function(fn)
+                fn()
+            end)
+        end)
+
+        after_each(function()
+            checktime_stub:revert()
+            schedule_stub:revert()
+        end)
+
+        it("calls checktime for each file-mutating kind", function()
+            for _, kind in ipairs({
+                "edit",
+                "create",
+                "write",
+                "delete",
+                "move",
+            }) do
+                checktime_stub:reset()
+                local tc_id = "tc-" .. kind
+                local session = make_session({
+                    [tc_id] = { kind = kind, status = "in_progress" },
+                })
+
+                SessionManager._on_tool_call_update(
+                    session,
+                    { tool_call_id = tc_id, status = "completed" }
+                )
+
+                assert.spy(checktime_stub).was.called(1)
+            end
+        end)
+
+        it("does not call checktime for failed tool calls", function()
+            local session = make_session({
+                ["tc-1"] = { kind = "edit", status = "in_progress" },
+            })
+
+            SessionManager._on_tool_call_update(
+                session,
+                { tool_call_id = "tc-1", status = "failed" }
+            )
+
+            assert.spy(checktime_stub).was.called(0)
+        end)
+
+        it("does not call checktime for non-mutating kinds", function()
+            local session = make_session({
+                ["tc-1"] = { kind = "read", status = "in_progress" },
+            })
+
+            SessionManager._on_tool_call_update(
+                session,
+                { tool_call_id = "tc-1", status = "completed" }
+            )
+
+            assert.spy(checktime_stub).was.called(0)
+        end)
+
+        it("does not call checktime when tracker is missing", function()
+            local debug_stub = spy.stub(Logger, "debug")
+            local session = make_session({})
+
+            SessionManager._on_tool_call_update(
+                session,
+                { tool_call_id = "tc-missing", status = "completed" }
+            )
+
+            assert.spy(checktime_stub).was.called(0)
+            debug_stub:revert()
+        end)
+    end)
 end)