From 2cb697e9f42a5b5988e5d3ab73ffb18fd112eb20 Mon Sep 17 00:00:00 2001
From: Liam <33645555+lj3954@users.noreply.github.com>
Date: Thu, 28 Aug 2025 15:32:15 +0000
Subject: [PATCH] copilot: Use updated Copilot Chat model schema (#33007)

Use the latest Copilot Chat model schema, matching what is used in
VSCode, to get more data about available models than was previously
accessible. Replace hardcoded default model (gpt-4.1) with the default
model included in JSON. Other data like premium request multipliers
could be used in the future if Zed implements a way for models to
display additional details about themselves, such as with tooltips on
hover.

Release Notes:

- N/A

---------

Co-authored-by: Peter Tripp <peter@zed.dev>
---
 crates/copilot/src/copilot_chat.rs | 52 +++++++++++++++++++++++-------
 1 file changed, 41 insertions(+), 11 deletions(-)

diff --git a/crates/copilot/src/copilot_chat.rs b/crates/copilot/src/copilot_chat.rs
index e8e2251648e4b941fe616b4524337fe565513950..bfddba0e2f8a41e3ed234b21ee52454d104c9dd2 100644
--- a/crates/copilot/src/copilot_chat.rs
+++ b/crates/copilot/src/copilot_chat.rs
@@ -62,12 +62,6 @@ impl CopilotChatConfiguration {
     }
 }
 
-// Copilot's base model; defined by Microsoft in premium requests table
-// This will be moved to the front of the Copilot model list, and will be used for
-// 'fast' requests (e.g. title generation)
-// https://docs.github.com/en/copilot/managing-copilot/monitoring-usage-and-entitlements/about-premium-requests
-const DEFAULT_MODEL_ID: &str = "gpt-4.1";
-
 #[derive(Clone, Copy, Serialize, Deserialize, Debug, Eq, PartialEq)]
 #[serde(rename_all = "lowercase")]
 pub enum Role {
@@ -101,22 +95,39 @@ where
     Ok(models)
 }
 
-#[derive(Clone, Serialize, Deserialize, Debug, Eq, PartialEq)]
+#[derive(Clone, Serialize, Deserialize, Debug, PartialEq)]
 pub struct Model {
+    billing: ModelBilling,
     capabilities: ModelCapabilities,
     id: String,
     name: String,
     policy: Option<ModelPolicy>,
     vendor: ModelVendor,
+    is_chat_default: bool,
+    // The model with this value true is selected by VSCode copilot if a premium request limit is
+    // reached. Zed does not currently implement this behaviour
+    is_chat_fallback: bool,
     model_picker_enabled: bool,
 }
 
+#[derive(Clone, Serialize, Deserialize, Debug, PartialEq)]
+struct ModelBilling {
+    is_premium: bool,
+    multiplier: f64,
+    // List of plans a model is restricted to
+    // Field is not present if a model is available for all plans
+    #[serde(default)]
+    restricted_to: Option<Vec<String>>,
+}
+
 #[derive(Clone, Serialize, Deserialize, Debug, Eq, PartialEq)]
 struct ModelCapabilities {
     family: String,
     #[serde(default)]
     limits: ModelLimits,
     supports: ModelSupportedFeatures,
+    #[serde(rename = "type")]
+    model_type: String,
 }
 
 #[derive(Default, Clone, Serialize, Deserialize, Debug, Eq, PartialEq)]
@@ -602,6 +613,7 @@ async fn get_models(
         .into_iter()
         .filter(|model| {
             model.model_picker_enabled
+                && model.capabilities.model_type.as_str() == "chat"
                 && model
                     .policy
                     .as_ref()
@@ -610,9 +622,7 @@ async fn get_models(
         .dedup_by(|a, b| a.capabilities.family == b.capabilities.family)
         .collect();
 
-    if let Some(default_model_position) =
-        models.iter().position(|model| model.id == DEFAULT_MODEL_ID)
-    {
+    if let Some(default_model_position) = models.iter().position(|model| model.is_chat_default) {
         let default_model = models.remove(default_model_position);
         models.insert(0, default_model);
     }
@@ -630,7 +640,9 @@ async fn request_models(
         .uri(models_url.as_ref())
         .header("Authorization", format!("Bearer {}", api_token))
         .header("Content-Type", "application/json")
-        .header("Copilot-Integration-Id", "vscode-chat");
+        .header("Copilot-Integration-Id", "vscode-chat")
+        .header("Editor-Version", "vscode/1.103.2")
+        .header("x-github-api-version", "2025-05-01");
 
     let request = request_builder.body(AsyncBody::empty())?;
 
@@ -801,6 +813,10 @@ mod tests {
         let json = r#"{
               "data": [
                 {
+                  "billing": {
+                    "is_premium": false,
+                    "multiplier": 0
+                  },
                   "capabilities": {
                     "family": "gpt-4",
                     "limits": {
@@ -814,6 +830,8 @@ mod tests {
                     "type": "chat"
                   },
                   "id": "gpt-4",
+                  "is_chat_default": false,
+                  "is_chat_fallback": false,
                   "model_picker_enabled": false,
                   "name": "GPT 4",
                   "object": "model",
@@ -825,6 +843,16 @@ mod tests {
                     "some-unknown-field": 123
                 },
                 {
+                  "billing": {
+                    "is_premium": true,
+                    "multiplier": 1,
+                    "restricted_to": [
+                      "pro",
+                      "pro_plus",
+                      "business",
+                      "enterprise"
+                    ]
+                  },
                   "capabilities": {
                     "family": "claude-3.7-sonnet",
                     "limits": {
@@ -848,6 +876,8 @@ mod tests {
                     "type": "chat"
                   },
                   "id": "claude-3.7-sonnet",
+                  "is_chat_default": false,
+                  "is_chat_fallback": false,
                   "model_picker_enabled": true,
                   "name": "Claude 3.7 Sonnet",
                   "object": "model",