feat: add display.modelOverride for custom model display names

Users can now set a fully custom model name in their config:

  { "display": { "modelOverride": "zane's intelligent opus 4.6" } }

When set, the override completely replaces the auto-detected model
name (while preserving the provider qualifier like "| Bedrock").

Follows the same pattern as customLine: string type, max 80 chars,
empty string means disabled (falls through to modelFormat).

src/config.ts

@@ -90,6 +90,7 @@ export interface HudConfig {
     sevenDayThreshold: number;
     environmentThreshold: number;
     modelFormat: ModelFormatMode;
+    modelOverride: string;
     customLine: string;
   };
   colors: HudColorOverrides;
@@ -128,6 +129,7 @@ export const DEFAULT_CONFIG: HudConfig = {
     sevenDayThreshold: 80,
     environmentThreshold: 0,
     modelFormat: 'full',
+    modelOverride: '',
     customLine: '',
   },
   colors: {
@@ -340,6 +342,9 @@ export function mergeConfig(userConfig: Partial<HudConfig>): HudConfig {
     modelFormat: validateModelFormat(migrated.display?.modelFormat)
       ? migrated.display.modelFormat
       : DEFAULT_CONFIG.display.modelFormat,
+    modelOverride: typeof migrated.display?.modelOverride === 'string'
+      ? migrated.display.modelOverride.slice(0, 80)
+      : DEFAULT_CONFIG.display.modelOverride,
     customLine: typeof migrated.display?.customLine === 'string'
       ? migrated.display.customLine.slice(0, 80)
       : DEFAULT_CONFIG.display.customLine,

src/render/lines/project.ts

@@ -9,7 +9,7 @@ export function renderProjectLine(ctx: RenderContext): string | null {
   const parts: string[] = [];
 
   if (display?.showModel !== false) {
-    const model = formatModelName(getModelName(ctx.stdin), ctx.config?.display?.modelFormat);
+    const model = formatModelName(getModelName(ctx.stdin), ctx.config?.display?.modelFormat, ctx.config?.display?.modelOverride);
     const providerLabel = getProviderLabel(ctx.stdin);
     const showUsage = display?.showUsage !== false;
     const hasApiKey = !!process.env.ANTHROPIC_API_KEY;

src/render/session-line.ts

@@ -12,7 +12,7 @@ const DEBUG = process.env.DEBUG?.includes('claude-hud') || process.env.DEBUG ===
  * Used for compact layout mode.
  */
 export function renderSessionLine(ctx: RenderContext): string {
-  const model = formatModelName(getModelName(ctx.stdin), ctx.config?.display?.modelFormat);
+  const model = formatModelName(getModelName(ctx.stdin), ctx.config?.display?.modelFormat, ctx.config?.display?.modelOverride);
 
   const rawPercent = getContextPercent(ctx.stdin);
   const bufferedPercent = getBufferedPercent(ctx.stdin);

src/stdin.ts

@@ -167,13 +167,20 @@ export function stripContextSuffix(name: string): string {
 }
 
 /**
- * Formats a model name according to the user's chosen display format.
+ * Formats a model name according to the user's chosen display settings.
+ *
+ * When `override` is set, it replaces the model name entirely.
+ * Otherwise, `format` controls how the raw name is abbreviated:
  *
  *   full:    Return raw name unchanged   (e.g. "Opus 4.6 (1M context)")
  *   compact: Strip context-window suffix (e.g. "Opus 4.6")
  *   short:   Strip context suffix AND leading "Claude " prefix (e.g. "Opus 4.6")
  */
-export function formatModelName(name: string, format?: ModelFormatMode): string {
+export function formatModelName(name: string, format?: ModelFormatMode, override?: string): string {
+  if (override) {
+    return override;
+  }
+
   if (!format || format === 'full') {
     return name;
   }

tests/config.test.js

@@ -135,6 +135,24 @@ test('mergeConfig falls back to full for invalid modelFormat', () => {
   assert.equal(mergeConfig({ display: { modelFormat: null } }).display.modelFormat, 'full');
 });
 
+test('mergeConfig defaults modelOverride to empty string', () => {
+  const config = mergeConfig({});
+  assert.equal(config.display.modelOverride, '');
+});
+
+test('mergeConfig preserves modelOverride and truncates long values', () => {
+  const override = 'x'.repeat(120);
+  const config = mergeConfig({ display: { modelOverride: override } });
+  assert.equal(config.display.modelOverride.length, 80);
+  assert.equal(config.display.modelOverride, override.slice(0, 80));
+});
+
+test('mergeConfig falls back to empty for non-string modelOverride', () => {
+  assert.equal(mergeConfig({ display: { modelOverride: 123 } }).display.modelOverride, '');
+  assert.equal(mergeConfig({ display: { modelOverride: null } }).display.modelOverride, '');
+  assert.equal(mergeConfig({ display: { modelOverride: true } }).display.modelOverride, '');
+});
+
 test('getConfigPath respects CLAUDE_CONFIG_DIR', async () => {
   const originalConfigDir = process.env.CLAUDE_CONFIG_DIR;
   const customConfigDir = await mkdtemp(path.join(tmpdir(), 'claude-hud-config-dir-'));

tests/core.test.js

@@ -319,6 +319,17 @@ test('formatModelName short mode strips context suffix and Claude prefix', () =>
   assert.equal(formatModelName('claude Opus 4.5', 'short'), 'Opus 4.5');
 });
 
+test('formatModelName override replaces model name entirely', () => {
+  // Override takes precedence over format
+  assert.equal(formatModelName('Claude Opus 4.5', 'full', "zane's intelligent opus"), "zane's intelligent opus");
+  assert.equal(formatModelName('Claude Opus 4.5', 'compact', 'My Model'), 'My Model');
+  assert.equal(formatModelName('Claude Opus 4.5', 'short', 'Custom'), 'Custom');
+  assert.equal(formatModelName('Claude Opus 4.5', undefined, 'Override'), 'Override');
+  // Empty override is treated as unset (falls through to format)
+  assert.equal(formatModelName('Claude Opus 4.5 (1M context)', 'compact', ''), 'Claude Opus 4.5');
+  assert.equal(formatModelName('Opus 4.6', 'full', ''), 'Opus 4.6');
+});
+
 test('bedrock model detection recognizes bedrock ids', () => {
   assert.ok(isBedrockModelId('anthropic.claude-3-5-sonnet-20240620-v1:0'));
   assert.ok(isBedrockModelId('eu.anthropic.claude-opus-4-5-20251101-v1:0'));