fix: deduplicate slash command collisions

CHANGELOG.md

@@ -4,6 +4,8 @@ All notable changes to this project will be documented in this file.
 
 ## [Unreleased]
 
+- Chat: the `/` command menu no longer lists a skill twice when a command shares its name.
+
 ## [1.17.1] - 2026-07-29
 
 - **Chat tools:** Bash tool cards now show output before a command finishes, keep it in a fixed-height pane, and follow new lines until you scroll away. Long-running commands no longer remain at a 300-second duration, and their timers continue until they finish.

packages/ui/src/components/chat/CommandAutocomplete.tsx

@@ -10,6 +10,7 @@ import { useI18n } from '@/lib/i18n';
 import { useUIStore } from '@/stores/useUIStore';
 import { isVSCodeRuntime } from '@/lib/desktop';
 import { useMobileAutocompleteMaxHeight } from './useMobileAutocompleteMaxHeight';
+import { commandMatchesSearch, mergeCommandAutocompleteItems } from './commandAutocompleteItems';
 
 type CommandSource = 'openchamber' | 'opencode' | 'skill';
 
@@ -18,6 +19,7 @@ export interface CommandInfo {
   name: string;
   source: CommandSource;
   description?: string;
+  searchAliases?: string[];
   agent?: string;
   model?: string;
   isBuiltIn?: boolean;
@@ -191,14 +193,11 @@ export const CommandAutocomplete = React.forwardRef<CommandAutocompleteHandle, C
             : []
           ),
         ];
-        const allCommands = [...builtInCommands, ...customCommands, ...skillCommands];
+        const allCommands = mergeCommandAutocompleteItems(builtInCommands, customCommands, skillCommands);
 
         const allowInitCommand = !hasMessagesInCurrentSession;
         const filtered = (searchQuery
-          ? allCommands.filter(cmd =>
-              fuzzyMatch(cmd.name, searchQuery) ||
-              (cmd.description && fuzzyMatch(cmd.description, searchQuery))
-            )
+          ? allCommands.filter(cmd => commandMatchesSearch(cmd, searchQuery))
           : allCommands).filter(cmd => allowInitCommand || cmd.name !== 'init');
 
         filtered.sort((a, b) => {

packages/ui/src/components/chat/__tests__/commandAutocompleteItems.test.ts

@@ -0,0 +1,157 @@
+import { describe, expect, test } from 'bun:test';
+import { commandMatchesSearch, mergeCommandAutocompleteItems } from '../commandAutocompleteItems';
+
+interface Item {
+  name: string;
+  source: 'openchamber' | 'opencode' | 'skill';
+  description?: string;
+  searchAliases?: string[];
+  isBuiltIn?: boolean;
+  isSkill?: boolean;
+}
+
+describe('mergeCommandAutocompleteItems', () => {
+  test('retains the discovered skill and command search metadata for #1550', () => {
+    const commands: Item[] = [{
+      name: 'grill-with-docs',
+      source: 'opencode',
+      description: 'Plugin command description',
+      isSkill: true,
+    }];
+    const skills: Item[] = [{
+      name: 'grill-with-docs',
+      source: 'skill',
+      description: 'Canonical skill description',
+      isSkill: true,
+    }];
+
+    const merged = mergeCommandAutocompleteItems([], commands, skills);
+
+    expect(merged).toEqual([{
+      ...skills[0],
+      searchAliases: ['Plugin command description'],
+    }]);
+    expect(commandMatchesSearch(merged[0], 'plugin command')).toBe(true);
+  });
+
+  test('built-ins win collisions with commands and skills without losing search aliases', () => {
+    const builtIn: Item = {
+      name: 'summary',
+      source: 'openchamber',
+      description: 'Summarize this session',
+      isBuiltIn: true,
+    };
+    const command: Item = {
+      name: 'summary',
+      source: 'opencode',
+      description: 'Plugin session digest',
+    };
+    const skill: Item = {
+      name: 'summary',
+      source: 'skill',
+      description: 'Skill session recap',
+      isSkill: true,
+    };
+
+    expect(mergeCommandAutocompleteItems([builtIn], [command], [skill])).toEqual([{
+      ...builtIn,
+      searchAliases: ['Plugin session digest', 'Skill session recap'],
+    }]);
+  });
+
+  test('OpenCode built-ins also win collisions with discovered skills', () => {
+    const builtIn: Item = {
+      name: 'review',
+      source: 'opencode',
+      description: 'Review workspace changes',
+      isBuiltIn: true,
+    };
+    const skill: Item = {
+      name: 'review',
+      source: 'skill',
+      description: 'Review skill',
+      isSkill: true,
+    };
+
+    expect(mergeCommandAutocompleteItems([], [builtIn], [skill])).toEqual([{
+      ...builtIn,
+      searchAliases: ['Review skill'],
+    }]);
+  });
+
+  test('deduplicates every pairwise source collision by executable precedence', () => {
+    const builtIn: Item = { name: 'compact', source: 'openchamber', isBuiltIn: true };
+    const command: Item = { name: 'compact', source: 'opencode' };
+    const skill: Item = { name: 'compact', source: 'skill', isSkill: true };
+
+    expect(mergeCommandAutocompleteItems([builtIn], [command], [])[0]).toBe(builtIn);
+    expect(mergeCommandAutocompleteItems([builtIn], [], [skill])[0]).toBe(builtIn);
+    expect(mergeCommandAutocompleteItems([], [command], [skill])[0]).toBe(skill);
+  });
+
+  test('OpenCode skill-commands win custom commands and yield to discovered skills', () => {
+    const command: Item = { name: 'deploy', source: 'opencode', description: 'Custom deploy' };
+    const skillCommand: Item = {
+      name: 'deploy',
+      source: 'opencode',
+      description: 'OpenCode skill command',
+      isSkill: true,
+    };
+    const skill: Item = {
+      name: 'deploy',
+      source: 'skill',
+      description: 'Discovered deploy skill',
+      isSkill: true,
+    };
+
+    expect(mergeCommandAutocompleteItems([], [command, skillCommand], [])).toEqual([{
+      ...skillCommand,
+      searchAliases: ['Custom deploy'],
+    }]);
+    expect(mergeCommandAutocompleteItems([], [command, skillCommand], [skill])).toEqual([{
+      ...skill,
+      searchAliases: ['OpenCode skill command', 'Custom deploy'],
+    }]);
+  });
+
+  test('keeps a case-distinct command when the built-in is disabled', () => {
+    const builtIn: Item = { name: 'init', source: 'openchamber', isBuiltIn: true };
+    const command: Item = { name: 'Init', source: 'opencode', description: 'Custom init' };
+    const merged = mergeCommandAutocompleteItems([builtIn], [command], []);
+
+    expect(merged).toEqual([builtIn, command]);
+    expect(merged.filter((item) => item.name !== 'init')).toEqual([command]);
+  });
+
+  test('keeps first-seen ordering and unrelated commands', () => {
+    const builtIns: Item[] = [{ name: 'undo', source: 'openchamber' }];
+    const commands: Item[] = [
+      { name: 'test', source: 'opencode' },
+      { name: 'deploy', source: 'opencode' },
+    ];
+    const skills: Item[] = [
+      { name: 'deploy', source: 'skill', isSkill: true },
+      { name: 'explain', source: 'skill', isSkill: true },
+    ];
+
+    const merged = mergeCommandAutocompleteItems(builtIns, commands, skills);
+
+    expect(merged.map((item) => item.name)).toEqual(['undo', 'test', 'deploy', 'explain']);
+    expect(merged[2]).toBe(skills[0]);
+  });
+
+  test('deduplicates repeated entries within each source without mutating inputs', () => {
+    const first: Item = { name: 'test', source: 'opencode', description: 'First' };
+    const duplicate: Item = { name: 'test', source: 'opencode', description: 'Second' };
+
+    expect(mergeCommandAutocompleteItems([], [first, duplicate], [])).toEqual([{
+      ...first,
+      searchAliases: ['Second'],
+    }]);
+    expect(first.searchAliases).toBe(undefined);
+  });
+
+  test('handles empty inputs', () => {
+    expect(mergeCommandAutocompleteItems([], [], [])).toEqual([]);
+  });
+});

packages/ui/src/components/chat/commandAutocompleteItems.ts

@@ -0,0 +1,70 @@
+import { fuzzyMatch } from '@/lib/utils';
+
+export interface CommandAutocompleteSearchItem {
+  name: string;
+  description?: string;
+  searchAliases?: string[];
+  isBuiltIn?: boolean;
+  isSkill?: boolean;
+}
+
+function addSearchAliases<T extends CommandAutocompleteSearchItem>(winner: T, duplicate: T): T {
+  const existingAliases = winner.searchAliases ?? [];
+  const aliases = [
+    ...existingAliases,
+    ...(winner.name === duplicate.name ? [] : [duplicate.name]),
+    ...(duplicate.description ? [duplicate.description] : []),
+    ...(duplicate.searchAliases ?? []),
+  ].filter((alias, index, values) => alias !== winner.description && values.indexOf(alias) === index);
+  const unchanged = aliases.length === existingAliases.length
+    && aliases.every((alias, index) => alias === existingAliases[index]);
+
+  return unchanged ? winner : { ...winner, searchAliases: aliases };
+}
+
+/**
+ * Precedence is local command, discovered skill, OpenCode skill-command, then
+ * custom/plugin command. Identity matches session.command's case-sensitive lookup.
+ */
+export function mergeCommandAutocompleteItems<T extends CommandAutocompleteSearchItem>(
+  builtIns: T[],
+  commands: T[],
+  skills: T[],
+): T[] {
+  const merged: T[] = [];
+  const byName = new Map<string, { index: number; item: T; precedence: number }>();
+
+  const addItems = (items: T[], getPrecedence: (item: T) => number) => {
+    for (const item of items) {
+      const precedence = getPrecedence(item);
+      const identity = item.name;
+      const existing = byName.get(identity);
+      if (!existing) {
+        byName.set(identity, { index: merged.length, item, precedence });
+        merged.push(item);
+        continue;
+      }
+
+      const winner = precedence > existing.precedence
+        ? addSearchAliases(item, existing.item)
+        : addSearchAliases(existing.item, item);
+      merged[existing.index] = winner;
+      byName.set(identity, {
+        index: existing.index,
+        item: winner,
+        precedence: Math.max(existing.precedence, precedence),
+      });
+    }
+  };
+
+  addItems(builtIns, () => 3);
+  addItems(commands, (item) => item.isBuiltIn ? 3 : item.isSkill ? 1 : 0);
+  addItems(skills, () => 2);
+  return merged;
+}
+
+export function commandMatchesSearch(command: CommandAutocompleteSearchItem, query: string): boolean {
+  return fuzzyMatch(command.name, query)
+    || Boolean(command.description && fuzzyMatch(command.description, query))
+    || Boolean(command.searchAliases?.some((alias) => fuzzyMatch(alias, query)));
+}