[2025-09-30] Anthropic Claude Sonnet 4.5 is available in Copilot coding agent (#57746)

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

Author: timrogers

content/copilot/concepts/agents/coding-agent/about-coding-agent.md

@@ -142,9 +142,11 @@ Users can include hidden messages in issues assigned to {% data variables.produc
 * **{% data variables.copilot.copilot_coding_agent %} does not work in personal repositories owned by {% data variables.enterprise.prodname_managed_users %}**. This is because {% data variables.copilot.copilot_coding_agent %} requires {% data variables.product.company_short %}-hosted runners, which are not available to repositories owned by {% data variables.enterprise.prodname_managed_users %}. See [AUTOTITLE](/actions/using-github-hosted-runners/using-github-hosted-runners/about-github-hosted-runners).
 * **{% data variables.product.prodname_copilot_short %} doesn't account for content exclusions**. Content exclusions allow administrators to configure {% data variables.product.prodname_copilot_short %} to ignore certain files. When using {% data variables.copilot.copilot_coding_agent %}, {% data variables.product.prodname_copilot_short %} will not ignore these files, and will be able to see and update them. See [AUTOTITLE](/copilot/managing-copilot/configuring-and-auditing-content-exclusion/excluding-content-from-github-copilot).
 * **{% data variables.copilot.copilot_coding_agent %} only works with repositories hosted on {% data variables.product.github %}**. If your repository is stored using a different code hosting platform, {% data variables.product.prodname_copilot_short %} won't be able to work on it.
-* **You cannot change the AI model used by {% data variables.copilot.copilot_coding_agent %}**. The model is determined by {% data variables.product.company_short %} and does not inherit the model selected for {% data variables.copilot.copilot_chat %}.
+* **You cannot select the AI model used by {% data variables.copilot.copilot_coding_agent %}**. A model picker is not available to switch between models, and {% data variables.product.company_short %} reserves the right to change models at any time.
 
- Currently the model used by {% data variables.copilot.copilot_coding_agent %} is {% data variables.copilot.cca_current_model %}. {% data variables.product.github %} reserves the right to change this model.
+ If you are a {% data variables.copilot.copilot_pro %} or {% data variables.copilot.copilot_pro_plus %} subscriber, {% data variables.copilot.copilot_coding_agent %} uses {% data variables.copilot.copilot_claude_sonnet_45 %}.
+ 
+ If you are a {% data variables.copilot.copilot_for_business %} or {% data variables.copilot.copilot_enterprise %} subscriber, {% data variables.copilot.copilot_coding_agent %} uses {% data variables.copilot.cca_current_model %} by default, or {% data variables.copilot.copilot_claude_sonnet_45 %} if the model has been enabled by an administrator. See [AUTOTITLE](/copilot/concepts/policies).
 
 ## Hands-on practice