fix(composer): display configured model context limits

apps/desktop/src/lib/composer-models.ts

@@ -1,5 +1,6 @@
 import {
   bindingSupportsImages,
+  effectiveContextWindow,
   isImageGenerationModel,
   type ImageGenerationBindings,
   modelMatchesFilter,
@@ -43,13 +44,21 @@ export function composerModelsForProvider(
     const metadata = (discovered ?? []).find((model) =>
       sameComposerModelId(model.modelId, modelId),
     );
+    const binding = composerModelBinding(provider, modelId);
+    const contextWindow = effectiveContextWindow(
+      metadata?.contextWindow,
+      binding?.contextWindow,
+      binding?.contextWindowSource,
+    );
+    const contextLimit = contextWindow === undefined ? {} : { contextWindow };
     const displayName = modelId;
     return metadata
-      ? { ...metadata, modelId, displayName, providerId: provider.id }
+      ? { ...metadata, ...contextLimit, modelId, displayName, providerId: provider.id }
       : {
           modelId,
           displayName,
           providerId: provider.id,
+          ...contextLimit,
           capabilities: ["text"],
           source: "user" as const,
         };

apps/desktop/test/composer-models.test.mjs

@@ -63,6 +63,56 @@ test("configured models remain selectable when discovery is unavailable", () =>
   assert.equal(models[0].displayName, "my-model-v2");
 });
 
+test("Composer context labels use configured limits and retain them without discovery", () => {
+  const provider = {
+    id: "space-bunny",
+    models: [
+      {
+        ...binding("claude-opus-5-5"),
+        contextWindow: 500_000,
+        contextWindowSource: "user",
+      },
+    ],
+  };
+  const [discovered] = composerModelsForProvider(provider, [
+    { ...model("claude-opus-5-5"), contextWindow: 1_000_000 },
+  ]);
+
+  assert.equal(discovered.contextWindow, 500_000);
+
+  const [catalogOwned] = composerModelsForProvider(
+    {
+      id: "space-bunny",
+      models: [
+        {
+          ...binding("catalog-model"),
+          contextWindow: 128_000,
+          contextWindowSource: "catalog",
+        },
+      ],
+    },
+    [{ ...model("catalog-model"), contextWindow: 1_000_000 }],
+  );
+
+  assert.equal(catalogOwned.contextWindow, 1_000_000);
+
+  const [undiscovered] = composerModelsForProvider(
+    {
+      id: "space-bunny",
+      models: [
+        {
+          ...binding("custom-model"),
+          contextWindow: 333_333,
+          contextWindowSource: "user",
+        },
+      ],
+    },
+    undefined,
+  );
+
+  assert.equal(undiscovered.contextWindow, 333_333);
+});
+
 test("unmatched models expose the full thinking ladder unless a binding overrides it", () => {
   const provider = {
     id: "custom",

docs/spec/03-runtime/13-model-catalog-and-selection.md

@@ -442,6 +442,8 @@ retain the existing session configuration and permission boundaries.
 
 Warnings are non-blocking unless execution is impossible.
 
+Composer context-window labels resolve the exact binding with `effectiveContextWindow`: explicit user limits override discovery, catalog-owned limits follow discovery, and legacy bindings preserve their saved limits. A binding with a valid saved limit still displays it when discovery is unavailable. This display resolution does not modify the discovered catalog or runtime safety budgets.
+
 ### 11.1 Reasoning capability resolution
 
 1. Resolve published Pi thinking metadata for the exact physical model.

docs/spec/06-delivery/04-e2e-test-plan.md

@@ -17117,3 +17117,9 @@ host-created files. The full app's file-preview viewer is covered separately.
   Playwright can be supplied through `PI_TEST_PLAYWRIGHT`). Only the model server
   is simulated in the Electron flow. The fixture profile and screenshots stay
   under `.artifacts/` for inspection; no user profile or paid model is used.
+
+### E2E-COMPOSER-configured-context-window
+
+- **Steps:** Save a 500K user context limit for a model whose catalog publishes 1M. Open the Composer model list, then send a short message and inspect context usage. Repeat with a catalog-owned limit and with discovery unavailable.
+- **Expected:** The user-configured row and context inspector show 500K; a catalog-owned row follows the published limit; a configured model without discovery retains its saved context label. Model selection remains unchanged.
+- **Status:** Automated unit regression in `apps/desktop/test/composer-models.test.mjs` covers user overrides, catalog inheritance, and missing discovery; the full save → picker → message → context-inspector path remains a manual validation scenario.

docs/zh-CN/spec/03-runtime/13-model-catalog-and-selection.md

@@ -280,6 +280,8 @@ type ModelCatalogItem = {
 
 除非不可能执行，否则警告是非阻塞的。
 
+Composer 模型列表中的上下文窗口标签通过 `effectiveContextWindow` 按对应 binding 解析：显式的用户额度优先于发现信息；由目录管理的额度跟随发现结果；旧版 binding 保留已保存额度。即使模型发现不可用，只要已保存额度有效，也仍会显示该额度。该显示解析不会修改发现目录或运行时安全预算。
+
 ### 11.1 Reasoning capability resolution
 
 1. Resolve published Pi thinking metadata for the exact physical model.

docs/zh-CN/spec/06-delivery/04-e2e-test-plan.md

@@ -9449,3 +9449,9 @@ preload, API normalization, store events, ToolRow, and Markdown renderer.
 No provider credentials or paid model calls are required. The fixture ends at
 work-panel file-request routing; artifact bytes are verified from the real
 host-created files. The full app's file-preview viewer is covered separately.
+
+### E2E-COMPOSER-configured-context-window
+
+- **步骤：**为目录发布 1M 的模型保存 500K 用户额度。打开 Composer 模型列表，然后发送一条简短消息并检查上下文用量。对目录管理的额度以及模型发现不可用的情况重复验证。
+- **预期：**用户配置的模型行和上下文检查器显示 500K；目录管理的额度跟随已发布值；没有发现信息的已配置模型仍显示保存的额度。模型选择保持不变。
+- **状态：**`apps/desktop/test/composer-models.test.mjs` 自动覆盖用户覆盖值、目录继承值及发现不可用时保留额度；完整的“保存 → 模型列表 → 发送消息 → 上下文检查器”路径仍需手动验证。