search_engines parameter declared but never consumed (CLI --search-engines and MCP search_engines both ignored)

[zhibuli290]

Summary

The search_engines parameter (CLI --search-engines and MCP search_engines) is declared but never consumed — passing it has no effect on which engines run.

Repro

CLI (wigolo 0.2.1, npm latest):

wigolo search "gold price" --search-engines=duckduckgo,wikipedia
# Search: "gold price" (9 results, 9526ms, engines: bing)   ← bing still used, flag ignored

MCP (same version, via search_engines: ["duckduckgo", "wikipedia"]):

"engines_used": ["bing"]   ← parameter ignored

Also tried --search-engines=duckduckgo (single value) — same result.

Source evidence (current main branch)

• src/server/tool-schemas.ts:144 — parameter declared in the MCP schema:
  search_engines: { type: 'array', items: { type: 'string' }, description: 'Override engine selection' }
• Help text advertises it: --search-engines=a,b Override engine selection
• Zero consumers — grep -rn "search_engines|searchEngines" src/ shows only the schema declaration and internal engine-list variables (src/cli/shell.ts, src/daemon/rest/dispatch.ts). Nothing reads the parameter and passes it to handleSearch.
• Engine selection is instead hard-coded in src/search/core/core-provider.ts (intent/vertical auto-dispatch: bing, duckduckgo, wikipedia, marginalia, mojeek, ...). src/cli/tool-run.ts seeds [new DuckDuckGoEngine(), new BingEngine()] directly for headless runs.

Why it matters

Users cannot exclude specific engines. Concrete case: the Bing engine returns noisy dictionary/currency/visa results for ambiguous queries (e.g. "US ISM manufacturing PMI" — the "US" token is interpreted as USD/visa; verified via direct proxied request to bing.com, so it's Bing's semantics, not a network issue). The only workaround today is post-hoc: detect the noise and re-search elsewhere.

Expected behavior

Either:

1. Make the parameter actually work — pass the engine allowlist through to the core orchestrator (override the vertical auto-dispatch), or
2. Remove it from the help text and MCP schema until implemented.

Environment

• wigolo 0.2.1 (npm latest, 2026-07-19); also present on current main (clone date 2026-08-14)
• Windows 11

[Frankie-Xu]

I'll take this. The CLI/MCP/REST surfaces already accepted search_engines, but core auto-dispatch ignored it.

#363 wires the allowlist through the core orchestrator so --search-engines=duckduckgo,wikipedia actually overrides engine selection instead of still running Bing.