Document reasoning level customization for Copilot cloud agent (#62491)

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: timrogers <116134+timrogers@users.noreply.github.com>
Co-authored-by: hubwriter <hubwriter@github.com>

Author: 3 people

content/copilot/how-tos/use-copilot-agents/cloud-agent/changing-the-ai-model.md

@@ -2,7 +2,7 @@
 title: Changing the AI model for GitHub Copilot cloud agent
 shortTitle: Changing the AI model
 allowTitleToDifferFromFilename: true
-intro: 'In supported entrypoints, when starting a task with {% data variables.copilot.copilot_cloud_agent %}, you can select the model used.'
+intro: 'In supported entrypoints, when starting a task with {% data variables.copilot.copilot_cloud_agent %}, you can select the model used, and, for supported models, the reasoning level.'
 product: '{% data reusables.gated-features.copilot-cloud-agent %}<br><a href="https://github.com/features/copilot/plans?ref_product=copilot&ref_type=purchase&ref_style=button" target="_blank" class="btn btn-primary mt-3 mr-3 no-underline"><span>Sign up for {% data variables.product.prodname_copilot_short %}</span> {% octicon "link-external" height:16 %}</a>'
 versions:
   feature: copilot
@@ -35,3 +35,9 @@ The following options are currently available:
 
 {% data reusables.copilot.auto-model-option %}
 
+## Reasoning level
+
+Some models support configurable reasoning levels, which control how much time and effort the model spends reasoning before it responds. Higher reasoning levels can improve the quality of responses to complex tasks, but may take longer and use more {% data variables.product.prodname_ai_credits_short %}.
+
+If you select a model that supports configurable reasoning, a second dropdown menu appears so you can choose the reasoning level you want {% data variables.copilot.copilot_cloud_agent %} to use for that task. For more information about which models support configurable reasoning, see [AUTOTITLE](/copilot/reference/ai-models/supported-models#models-with-extended-capabilities).
+

content/copilot/reference/ai-models/supported-models.md

@@ -70,7 +70,8 @@ The latest {% data variables.product.prodname_copilot_short %} models support th
 Choosing a larger context window or higher reasoning will impact {% data variables.product.prodname_ai_credits_short %} consumption; more tokens will be consumed, so more credits will be used. For this reason, we recommend that you use the regular context window and regular reasoning by default, selecting the larger context window and higher reasoning for more complex tasks only.
 
 > [!NOTE]
-> * These extended capabilities are available in {% data variables.product.prodname_vscode %} and {% data variables.copilot.copilot_cli_short %} only.
+> * The 1 million token context window is available in {% data variables.product.prodname_vscode %} and {% data variables.copilot.copilot_cli_short %} only.
+> * Configurable reasoning levels are available in {% data variables.product.prodname_vscode %}, {% data variables.copilot.copilot_cli_short %}, and {% data variables.copilot.copilot_cloud_agent %}.
 > * Some models have extended capability pricing see [AUTOTITLE](/copilot/reference/copilot-billing/models-and-pricing#pricing-tables)
 
 {% rowheaders %}

data/reusables/copilot/optional-select-copilot-cloud-agent-model.md

@@ -1 +1 @@
-1. Optionally, you can use the dropdown menu to select the model that {% data variables.product.prodname_copilot_short %} will use. For more information, see [AUTOTITLE](/copilot/how-tos/use-copilot-agents/cloud-agent/changing-the-ai-model).
+1. Optionally, you can use the dropdown menu to select the model that {% data variables.product.prodname_copilot_short %} will use. If the selected model supports configurable reasoning, you can also use the dropdown menu to select the reasoning level. For more information, see [AUTOTITLE](/copilot/how-tos/use-copilot-agents/cloud-agent/changing-the-ai-model).