[2025-11-06] Deprecation of Sonnet 3.5 in Copilot [closing down] (#58329)

Co-authored-by: Mia Arts <107727642+its-mia@users.noreply.github.com>

data/reusables/copilot/model-use-cases/claude-35-sonnet.md

@@ -1,2 +0,0 @@
-{% data variables.copilot.copilot_claude_sonnet_35 %} is a good choice for everyday coding support—including writing documentation, answering language-specific questions, or generating boilerplate code. It offers helpful, direct answers without over-complicating the task.
-If you're working within cost constraints, {% data variables.copilot.copilot_claude_sonnet_35 %} is recommended as it delivers solid performance on many of the same tasks as {% data variables.copilot.copilot_claude_sonnet_37 %}, but with significantly lower resource usage.

data/reusables/copilot/model-use-cases/claude-haiku-45.md

@@ -0,0 +1,2 @@
+{% data variables.copilot.copilot_claude_haiku_45 %} is a good choice for everyday coding support—including writing documentation, answering language-specific questions, or generating boilerplate code. It offers helpful, direct answers without over-complicating the task. If you're working within cost constraints, {% data variables.copilot.copilot_claude_haiku_45 %} is recommended as it delivers solid performance on many of the same tasks as {% data variables.copilot.copilot_claude_sonnet_45 %}, but with lower resource usage.
+

data/tables/copilot/model-deprecation-history.yml

@@ -11,6 +11,10 @@
 # - retirement_date: The official retirement date for the model (YYYY-MM-DD).
 # - suggested_alternative: The model recommended for migration.
 
+- name: 'Claude Sonnet 3.5'
+  retirement_date: '2025-11-06'
+  suggested_alternative: 'Claude Sonnet 3.5'
+
 - name: 'Claude Opus 4'
   retirement_date: '2025-10-23'
   suggested_alternative: 'Claude Opus 4.1'

data/tables/copilot/model-multipliers.yml

@@ -11,16 +11,12 @@
 
 - name: Claude Haiku 4.5
   multiplier_paid: 0.33
-  multiplier_free: Not applicable
+  multiplier_free: 1
 
 - name: Claude Opus 4.1
   multiplier_paid: 10
   multiplier_free: Not applicable
 
-- name: Claude Sonnet 3.5
-  multiplier_paid: 1
-  multiplier_free: 1
-
 - name: Claude Sonnet 4
   multiplier_paid: 1
   multiplier_free: Not applicable

data/tables/copilot/model-release-status.yml

@@ -61,13 +61,6 @@
   ask_mode: true
   edit_mode: true
 
-- name: 'Claude Sonnet 3.5'
-  provider: 'Anthropic'
-  release_status: 'Closing down: 2025-11-06'
-  agent_mode: true
-  ask_mode: true
-  edit_mode: true
-
 - name: 'Claude Sonnet 4'
   provider: 'Anthropic'
   release_status: 'GA'

data/tables/copilot/model-supported-clients.yml

@@ -29,14 +29,6 @@
   xcode: true
   jetbrains: true
 
-- name: Claude Sonnet 3.5
-  dotcom: true
-  vscode: true
-  vs: true
-  eclipse: true
-  xcode: true
-  jetbrains: true
-
 - name: Claude Sonnet 4
   dotcom: true
   vscode: true

data/tables/copilot/model-supported-plans.yml

@@ -13,7 +13,7 @@
 # - enterprise: Availability on Copilot Enterprise.
 
 - name: Claude Haiku 4.5
-  free: false
+  free: true
   pro: true
   pro_plus: true
   business: true
@@ -26,13 +26,6 @@
   business: false
   enterprise: true
 
-- name: Claude Sonnet 3.5
-  free: true
-  pro: true
-  pro_plus: true
-  business: true
-  enterprise: true
-
 - name: Claude Sonnet 4
   free: false
   pro: true