fix: handle bare string for include_domains/exclude_domains in Zod schema search tools

[simply24365]

Summary

AI models sometimes return include_domains / exclude_domains as a bare
string ("reddit.com") instead of string[] (["reddit.com"]), causing
TypeError: f.join is not a function in search-section.tsx.

This was observed with the Xiaomi MIMO v2.5 model (OpenAI-compatible
endpoint), which does not enforce strict: true on function definitions.
The model can therefore produce type-invalid tool call arguments, which
Zod rejects at validation time — but the AI SDK still renders the raw
(unvalidated) input in the UI.

Changes

1. lib/schema/search.tsx — Replaced z.array(z.string()) with
   z.union([z.string(), z.array(z.string())]) + .transform() so that
   bare strings are coerced into single-element arrays at Zod validation
   time, preventing the tool call from being rejected. Applied to both
   searchSchema and strictSearchSchema for include_domains and
   exclude_domains.

2. components/search-section.tsx — Added Array.isArray guard
   before .join() as defense-in-depth.

Suggestion

This type of mismatch can affect any array-typed tool parameter. Consider
enabling strict: true on tools for providers that support it, or
implementing repairToolCall in ToolLoopAgent to automatically fix and
retry failed tool calls.

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Project	Deployment	Actions	Updated (UTC)
morphic	Ready	Preview, Comment	Jul 1, 2026 2:13pm

[miurla]

Thanks for the fix and the clear write-up. LGTM!