refactor: move model selector to specific provider

Author: pxwg

lua/CopilotChat/client.lua

@@ -63,6 +63,7 @@ local class = require('CopilotChat.utils.class')
 local files = require('CopilotChat.utils.files')
 local orderedmap = require('CopilotChat.utils.orderedmap')
 local stringbuffer = require('CopilotChat.utils.stringbuffer')
+local model = require('fidget.notification.model')
 
 --- Constants
 local RESOURCE_SHORT_FORMAT = '# %s\n```%s start_line=% end_line=%s\n%s\n```'
@@ -299,28 +300,6 @@ function Client:ask(opts)
   opts = opts or {}
   local job_id = utils.uuid()
 
-  -- handle auto model selection
-  if opts.model == 'auto' then
-    notify.publish(notify.STATUS, 'Auto-selecting model...')
-    local provider_name = 'copilot'
-    local provider = self:get_providers():get(provider_name)
-
-    if provider and provider.route_model then
-      local headers = self:authenticate(provider_name)
-      local selected_model, err = provider.route_model(headers, { 'auto' })
-
-      if selected_model then
-        opts.model = selected_model
-      else
-        log.warn('Auto mode failed, falling back to gpt-4o. Error: ' .. tostring(err))
-        opts.model = 'gpt-4o'
-      end
-    else
-      log.warn('Auto mode not supported, falling back to gpt-4o')
-      opts.model = 'gpt-4o'
-    end
-  end
-
   log.debug('Model:', opts.model)
   log.debug('Tools:', #opts.tools)
   log.debug('Resources:', #opts.resources)
@@ -341,6 +320,24 @@ function Client:ask(opts)
     error('Provider not found: ' .. provider_name)
   end
 
+  if provider.route_model then
+    if not opts.headless then
+      notify.publish(notify.STATUS, 'Routing model...')
+    end
+
+    local headers = self:authenticate(provider_name)
+    local resolved_model = provider.route_model(headers, opts)
+
+    if resolved_model and resolved_model ~= opts.model then
+      opts.model = resolved_model
+
+      model_config = models[opts.model]
+      if not model_config then
+        error('Routed model not found: ' .. opts.model)
+      end
+    end
+  end
+
   local options = {
     model = vim.tbl_extend('force', model_config, {
       id = opts.model:gsub(':' .. provider_name .. '$', ''),

lua/CopilotChat/config/providers.lua

@@ -649,39 +649,51 @@ M.copilot = {
     return models
   end,
 
-  route_model = function(headers, hints)
-    hints = hints or { 'auto' }
-    local token = headers['Authorization'] and headers['Authorization']:gsub('^Bearer%s+', '')
+  route_model = function(headers, opts)
+    local model_id = opts.model
+    if model_id ~= 'auto' then
+      return model_id
+    end
+
+    local token = headers['Authorization']
     if not token then
-      return nil, 'No authorization token available'
+      log.warn('No authorization token available for auto model resolution')
+      return 'gpt-4.1' -- Fallback model
     end
 
     local url = 'https://api.individual.githubcopilot.com/models/session'
     local response, err = curl.post(url, {
       headers = {
-        ['Authorization'] = 'Bearer ' .. token,
+        ['Authorization'] = token,
         ['editor-version'] = 'vscode/1.109.0-insider',
         ['user-agent'] = 'GitHubCopilotChat/0.38.0',
         ['x-github-api-version'] = '2025-10-01',
       },
-      body = { auto_mode = { model_hints = hints } },
+      body = { auto_mode = { model_hints = { 'auto' } } },
       json_response = true,
       json_request = true,
     })
 
     if err then
-      return nil, 'Auto selection request failed: ' .. tostring(err)
+      log.warn('Auto selection request failed: ' .. tostring(err) .. '. Falling back to gpt-4.1.')
+      return 'gpt-4.1'
     end
 
     if not response or response.status ~= 200 then
-      return nil, 'Auto selection returned status: ' .. tostring(response and response.status or 'unknown')
+      log.warn(
+        'Auto selection returned status: '
+          .. tostring(response and response.status or 'unknown')
+          .. '. Falling back to gpt-4.1.'
+      )
+      return 'gpt-4.1'
     end
 
     if not response.body or not response.body.selected_model then
-      return nil, 'No model selected in response'
+      log.warn('No model selected in response. Falling back to gpt-4.1.')
+      return 'gpt-4.1'
     end
 
-    return response.body.selected_model, nil
+    return response.body.selected_model
   end,
 
   prepare_input = function(inputs, opts)