Search Switch

1import { atom, read, update } from 'claude-code'
2import type { EngineInterface, Register } from 'claude-code'
3
4import type { SearchMode } from '../types'
5
6const mode = atom({ plugin: 'search-switch', key: 'mode' } as const, 'native' as SearchMode)
7
8const OPTIONS = [
9  { value: 'native', label: 'Native' },
10  { value: 'exa', label: 'Exa / Firecrawl' },
11]
12
13const NATIVE_TOOLS = new Set(['WebSearch', 'WebFetch'])
14// Exa's MCP tools, whether it is installed as a plugin or as a plain MCP server.
15const isExaTool = (tool: string) => tool.startsWith('mcp__plugin_exa_') || tool.startsWith('mcp__exa__')
16const isFirecrawlCommand = (command: unknown) =>
17  typeof command === 'string' && /^\s*(npx\s+(-y\s+)?)?firecrawl(-cli)?\b/.test(command)
18
19const GUIDE: Record<SearchMode, string> = {
20  native:
21    'Web search mode: Native. For web search and fetching pages, use the built-in WebSearch and WebFetch tools. ' +
22    'Do not use the Exa MCP tools or the firecrawl CLI; they are blocked in this mode.',
23  exa:
24    'Web search mode: Exa / Firecrawl. Do not use the built-in WebSearch or WebFetch tools; they are blocked in this mode. ' +
25    'For web search, use the Exa MCP tools (web_search_exa, and web_fetch_exa to read a page). ' +
26    'For scraping, crawling or mapping a site, or when a page needs JavaScript rendering, use the firecrawl CLI through the Firecrawl skills. ' +
27    'If a tool fails because it is not signed in or is rate-limited, tell the user instead of falling back to WebSearch or WebFetch.',
28}
29
30const setMode = async ($: EngineInterface, next: SearchMode) => {
31  await update($, mode, () => next)
32  await $.store.set('mode', next)
33}
34
35const parseMode = (raw: string): SearchMode | undefined => {
36  const v = raw.trim().toLowerCase()
37  if (v === 'native') return 'native'
38  if (v === 'exa' || v === 'firecrawl' || v === 'exa/firecrawl') return 'exa'
39  return undefined
40}
41
42export const register: Register = on => {
43  on('session.start', async ($, e, next) => {
44    const saved = await $.store.get('mode').catch(() => undefined)
45    if (saved === 'native' || saved === 'exa') await update($, mode, () => saved)
46    await $.command.register({ name: 'search', description: 'Show or set the web search mode: native or exa' })
47    return next(e)
48  })
49
50  on('command.run', { command: 'search' }, async ($, e) => {
51    if (!e.args.trim()) return { text: `Search mode: ${(await read($, mode)) === 'exa' ? 'Exa / Firecrawl' : 'Native'}` }
52    const picked = parseMode(e.args)
53    if (!picked) return { text: 'Use /search native or /search exa' }
54    await setMode($, picked)
55    return { text: `Search mode set to ${picked === 'exa' ? 'Exa / Firecrawl' : 'Native'}` }
56  })
57
58  // Tell Claude which search tools to use.
59  on('prompt.compose', async ($, e, next) => {
60    const composed = await next(e)
61    const current = await read($, mode)
62    return { sections: [...composed.sections, { id: 'search-switch:mode', text: GUIDE[current], scope: 'session' as const }] }
63  })
64
65  // Block the other side's tools so the choice holds.
66  on('tool.call', async ($, e, next) => {
67    const current = await read($, mode)
68    if (current === 'exa' && NATIVE_TOOLS.has(e.tool)) {
69      return { deny: `Search mode is Exa / Firecrawl, so ${e.tool} is blocked. Use the Exa MCP tools or the firecrawl CLI.` }
70    }
71    if (current === 'native' && isExaTool(e.tool)) {
72      return { deny: 'Search mode is Native, so Exa tools are blocked. Use WebSearch or WebFetch.' }
73    }
74    if (current === 'native' && e.tool === 'Bash' && isFirecrawlCommand((e as { command?: unknown }).command)) {
75      return { deny: 'Search mode is Native, so the firecrawl CLI is blocked. Use WebSearch or WebFetch.' }
76    }
77    return next(e)
78  }).catch(($, e, next) => next(e))
79
80  on('ui.render', { component: 'AbovePrompt' }, async ($, e, next) => {
81    const rest = await next(e)
82    if (e.props.hasSurvey) return rest
83
84    const { Box, Select, Text } = $.ui.resolve(e)
85    const current = await read($, mode)
86
87    return (
88      <Box>
89        <Select key="search-mode" label="Search" options={OPTIONS} value={current} onSelect={v => setMode($, v === 'exa' ? 'exa' : 'native')} />
90        <Text>  </Text>
91        {rest}
92      </Box>
93    )
94  })
95}
96

1export type SearchMode = 'native' | 'exa'
2
3declare module 'claude-code' {
4  interface PluginState {
5    'search-switch': { mode: SearchMode }
6  }
7}
8