fix(session): create sessions on the first prompt, one tab per session

lua/opencode/history.lua

@@ -1,3 +1,5 @@
+local log = require('opencode.log')
+
 local M = {}
 
 local cached_history = nil
@@ -26,12 +28,17 @@ M.write = function(prompt)
   end
   local file = io.open(path, 'a')
   if not file then
+    log.warn('history: could not open %s for appending', path)
     return false
   end
   local written = file:write(vim.json.encode(prompt) .. '\n')
   local closed = file:close()
   cached_history = nil
-  return written ~= nil and closed ~= nil
+  if written == nil or closed == nil then
+    log.warn('history: failed to append to %s', path)
+    return false
+  end
+  return true
 end
 
 ---@return string[]
@@ -49,7 +56,9 @@ M.read = function()
     for line in file:lines() do
       if is_json then
         local ok, prompt = pcall(vim.json.decode, line)
-        if ok and type(prompt) == 'string' then
+        if not ok then
+          log.warn('history: skipping undecodable line: %s', line)
+        elseif type(prompt) == 'string' then
           lines[#lines + 1] = prompt
         end
       elseif line:find('%S') then

lua/opencode/log.lua

@@ -2,9 +2,11 @@ local M = {}
 
 local config = require('opencode.config')
 
-local log_path = (config.logging and config.logging.outfile) or vim.fn.stdpath('log') .. '/opencode.log'
 local log_levels = { debug = 1, info = 2, warn = 3, error = 4 }
-local current_level = log_levels[(config.logging and config.logging.level or 'warn'):lower()] or 3
+
+local function log_path()
+  return (config.logging and config.logging.outfile) or vim.fn.stdpath('log') .. '/opencode.log'
+end
 
 local function caller_info()
   local level = 2
@@ -22,10 +24,12 @@ local function caller_info()
 end
 
 local function log(level, msg, ...)
-  if not config.logging.enabled then
+  local settings = config.logging or {}
+  if not settings.enabled then
     return
   end
-  if log_levels[level] < current_level then
+  local threshold = log_levels[(settings.level or 'warn'):lower()] or log_levels.warn
+  if log_levels[level] < threshold then
     return
   end
   local line = string.format(
@@ -35,7 +39,7 @@ local function log(level, msg, ...)
     caller_info(),
     string.format(msg, ...)
   )
-  local file = io.open(log_path, 'a')
+  local file = io.open(log_path(), 'a')
   if file then
     file:write(line)
     file:close()
@@ -56,7 +60,7 @@ function M.error(msg, ...)
 end
 
 function M.get_path()
-  return config.logging.enabled and log_path or nil
+  return config.logging and config.logging.enabled and log_path() or nil
 end
 
 --- Emit a user-visible notification and write the same message to the log.

lua/opencode/opencode_server.lua

@@ -22,7 +22,7 @@ local protocol_connection = require('opencode.protocols.connection')
 ---@field private _stream? {shutdown: fun(self: table)}
 ---@field private _requests table<table, true>
 ---@field private _observe? fun(connection: OpencodeServer, ref: {id: string, location?: OpencodeLocation}): OpencodeObservation
----@field private _close_observations? fun(connection: OpencodeServer)
+---@field private _close_observations? fun(connection: OpencodeServer, reason: string)
 local OpencodeServer = {}
 OpencodeServer.__index = OpencodeServer
 
@@ -38,7 +38,7 @@ local function ensure_vim_leave_autocmd()
     callback = function()
       local state = require('opencode.state')
       if state.opencode_server then
-        state.opencode_server:close()
+        state.opencode_server:close('vim exit')
       end
     end,
   })
@@ -217,8 +217,9 @@ function OpencodeServer:check_health()
   return protocol_connection.check_health(self)
 end
 
+---@param reason string Why the connection is going away; stranded prompts report it
 ---@return Promise<boolean>
-function OpencodeServer:close()
+function OpencodeServer:close(reason)
   if self.shutdown_promise:is_resolved() then
     return self.shutdown_promise
   end
@@ -228,7 +229,7 @@ function OpencodeServer:close()
   local close_observations = self._close_observations
   self._close_observations = nil
   if close_observations then
-    close_observations(self)
+    close_observations(self, reason or 'unspecified')
   end
   local requests = self._requests
   self._requests = {}
@@ -258,9 +259,10 @@ function OpencodeServer:close()
   return self.shutdown_promise
 end
 
+---@param reason? string
 ---@return Promise<boolean>
-function OpencodeServer:shutdown()
-  return self:close()
+function OpencodeServer:shutdown(reason)
+  return self:close(reason)
 end
 
 --- @class OpencodeServerSpawnOpts
@@ -352,7 +354,7 @@ function OpencodeServer:spawn(opts)
     self.job = nil
     self.handle = nil
     safe_call(opts.on_exit, exit_opts)
-    self:close()
+    self:close('server process exited')
   end)
 
   self.handle = self.job and self.job.pid

lua/opencode/port_mapping.lua

@@ -32,7 +32,11 @@ local function load()
   local content = file:read('*all')
   file:close()
   local ok, data = pcall(vim.json.decode, content or '')
-  return ok and data or {}
+  if not ok then
+    log.warn('port_mapping: discarding unreadable %s: %s', file_path(), tostring(data))
+    return {}
+  end
+  return data
 end
 
 --- @param mappings table<string, PortMapping>

lua/opencode/protocols/contract_check.lua

@@ -45,7 +45,12 @@ function M.check(connection)
         return nil
       end
       local ok, spec = pcall(vim.json.decode, response.body)
-      if not ok or type(spec.paths) ~= 'table' then
+      if not ok then
+        log.warn('contract check: could not decode /openapi.json: %s', tostring(spec))
+        return nil
+      end
+      if type(spec.paths) ~= 'table' then
+        log.warn('contract check: /openapi.json has no paths table')
         return nil
       end
 
@@ -70,7 +75,8 @@ function M.check(connection)
       end
       return missing
     end)
-    :catch(function()
+    :catch(function(err)
+      log.warn('contract check skipped: %s', tostring(err))
       return nil
     end)
 end

lua/opencode/protocols/observation.lua

@@ -1,3 +1,5 @@
+local log = require('opencode.log')
+
 local M = {}
 
 local resource_names = {
@@ -56,7 +58,7 @@ local resource_names = {
 ---@field on_release_resource? fun(observation: OpencodeObservation, resource: OpencodeObservedResource)
 ---@field on_unused? fun(observation: OpencodeObservation)
 ---@field on_stream_error? fun(observation: OpencodeObservation, message: string)
----@field on_close? fun(observation: OpencodeObservation)
+---@field on_close? fun(observation: OpencodeObservation, reason: string)
 
 ---@class OpencodeMessageSelection
 ---@field mode? string
@@ -452,6 +454,7 @@ local function stream_failure(connection, owner, reason)
   close_stream(connection)
   local message = type(reason) == 'table' and tostring(reason.message or reason.code or 'event stream disconnected')
     or tostring(reason or 'event stream disconnected')
+  log.warn('event stream failed (%s): %s', owner.runtime.name, message)
   for _, observation in pairs(connection.observations) do
     if observation._runtime.on_stream_error then
       observation._runtime.on_stream_error(observation, message)
@@ -472,7 +475,10 @@ local function decode_record(connection, owner)
     stream_failure(connection, owner, 'invalid ' .. owner.runtime.name .. ' event JSON')
     return
   end
-  owner.runtime.route_event(connection, event)
+  local routed, err = pcall(owner.runtime.route_event, connection, event)
+  if not routed then
+    log.error('event routing failed (%s): %s', owner.runtime.name, tostring(err))
+  end
 end
 
 local function consume_stream_chunk(connection, owner, chunk)
@@ -599,6 +605,13 @@ function Observation:_start_resource(resource)
     if owns_request() then
       self._loading[resource] = nil
       self._state.sync[resource] = M.sync_error('operation', err)
+      log.warn(
+        'observation %s load failed for %s (%s): %s',
+        self._session_id,
+        resource,
+        self._runtime.name,
+        tostring(err)
+      )
       self:_notify(resource)
     end
   end
@@ -727,11 +740,13 @@ function M.attach(connection, session, state, runtime)
   }, Observation)
 end
 
-function M.close(connection)
+---@param connection table
+---@param reason string Why the connection is closing; reaches every admission it strands
+function M.close(connection, reason)
   close_stream(connection)
   for _, observation in pairs(connection.observations) do
     if observation._runtime.on_close then
-      observation._runtime.on_close(observation)
+      observation._runtime.on_close(observation, reason)
     end
   end
   connection.observations = {}

lua/opencode/protocols/v1/observation.lua

@@ -981,8 +981,9 @@ local function track_submission(observation, result)
 end
 
 ---@param connection table
-function M.close(connection)
-  lifecycle.close(connection)
+---@param reason string
+function M.close(connection, reason)
+  lifecycle.close(connection, reason)
 end
 
 local function clear_unresolved_mentions(observation)
@@ -1023,8 +1024,8 @@ function M.new(connection, ref)
     on_stream_error = function(current, message)
       fail_submissions(current, 'V1 reply completion is unknown: ' .. message)
     end,
-    on_close = function(current)
-      fail_submissions(current, 'connection closed')
+    on_close = function(current, reason)
+      fail_submissions(current, 'connection closed (' .. tostring(reason) .. ')')
       clear_unresolved_mentions(current)
     end,
   })

lua/opencode/protocols/v2/normalize.lua

@@ -338,6 +338,9 @@ end
 ---@param key string|integer
 ---@return string
 local function synthetic_id(owner_id, kind, key)
+  if owner_id:find(':', 1, true) then
+    error('V2 observation: message id must not contain ":": ' .. owner_id)
+  end
   return owner_id .. ':' .. kind .. ':' .. tostring(key)
 end
 

lua/opencode/protocols/v2/observation.lua

@@ -53,9 +53,9 @@ function M.new(connection, ref)
     end,
     on_stream_error = actions.invalidate_submissions,
     ---@param current OpencodeObservation
-    on_close = function(current)
+    on_close = function(current, reason)
       ---@cast current OpencodeV2Observation
-      actions.invalidate_submissions(current, 'connection closed')
+      actions.invalidate_submissions(current, 'connection closed (' .. tostring(reason) .. ')')
     end,
   })
   ---@cast observation OpencodeV2Observation
@@ -68,8 +68,9 @@ function M.new(connection, ref)
 end
 
 ---@param connection OpencodeV2Connection
-function M.close(connection)
-  lifecycle.close(connection)
+---@param reason string
+function M.close(connection, reason)
+  lifecycle.close(connection, reason)
 end
 
 return M

lua/opencode/server_job.lua

@@ -508,7 +508,7 @@ function M.spawn_local_server(promise, port, hostname)
         end)
         :catch(function(err)
           log.notify(' Failed to start opencode server' .. vim.inspect(err), vim.log.levels.ERROR)
-          server:shutdown()
+          server:shutdown('startup probe failed')
           promise:reject(err)
         end)
     end,

lua/opencode/services/agent_model.lua

@@ -303,7 +303,7 @@ function M.sync_from_server()
       M.apply_server_selection(fact and fact.model)
     end)
     :catch(function(err)
-      log.debug('Failed to sync session model from server', { error = err })
+      log.warn('Failed to sync session model from server: %s', tostring(err))
     end)
 end