fix: disable Anthropic thinking to fix tool chain crash (#415)

* fix: disable Anthropic thinking to fix tool chain crash

Anthropic's API rejects requests that combine extended thinking with
forced tool_choice. The ToolLoopAgent enables thinking globally, and
prepareStep forces toolChoice for every tool chain step (create_new_artist,
create_release_report). This causes "Thinking may not be enabled when
tool_choice forces tool use" on any Anthropic model.

The Vercel AI SDK does not support overriding providerOptions per-step
(open issue vercel/ai#11761), so the fix must be at the constructor level.

Disables Anthropic thinking until the SDK adds per-step providerOptions
support or an alternative approach is implemented.

Made-with: Cursor

* fix: use fallback model for tool chain steps to avoid Anthropic thinking conflict

Instead of disabling Anthropic thinking globally, tool chain steps now
switch to openai/gpt-5-mini (via TOOL_CHAIN_FALLBACK_MODEL) when no
specific model is mapped in TOOL_MODEL_MAP.

This preserves extended thinking for regular Anthropic conversations
while ensuring forced toolChoice works during tool chain execution.

Made-with: Cursor

* chore: use openai/gpt-5.4-mini as tool chain fallback model

Made-with: Cursor

* style: fix prettier formatting on import

Made-with: Cursor

* refactor: remove TOOL_CHAIN_FALLBACK_MODEL, use TOOL_MODEL_MAP for all chain tools

Addresses code review feedback — use existing TOOL_MODEL_MAP pattern
instead of a separate fallback constant. All tool chain tools now have
explicit model entries in TOOL_MODEL_MAP.

Made-with: Cursor

---------

Co-authored-by: sswift <159544713+sswiftdrtv@users.noreply.github.com>

Author: sidneyswift

lib/chat/toolChains/getPrepareStepResult.ts

@@ -57,7 +57,6 @@ const getPrepareStepResult = (options: PrepareStepOptions): PrepareStepResult |
         result.messages = options.messages.concat(nextToolItem.messages);
       }
 
-      // Add model if specified for this tool
       const model = TOOL_MODEL_MAP[nextToolItem.toolName];
       if (model) {
         result.model = model;

lib/chat/toolChains/toolChains.ts

@@ -15,11 +15,25 @@ export type PrepareStepResult = {
   messages?: ModelMessage[];
 };
 
-// Map specific tools to their required models
+// Forced toolChoice is incompatible with Anthropic extended thinking.
+// Every tool used in a chain must have a model here to avoid the conflict.
 export const TOOL_MODEL_MAP: Record<string, LanguageModel> = {
   update_account_info: "gemini-2.5-pro",
-  // Add other tools that need specific models here
-  // e.g., create_segments: "gpt-4-turbo",
+  get_spotify_search: "openai/gpt-5.4-mini",
+  update_artist_socials: "openai/gpt-5.4-mini",
+  artist_deep_research: "openai/gpt-5.4-mini",
+  spotify_deep_research: "openai/gpt-5.4-mini",
+  get_artist_socials: "openai/gpt-5.4-mini",
+  get_spotify_artist_top_tracks: "openai/gpt-5.4-mini",
+  get_spotify_artist_albums: "openai/gpt-5.4-mini",
+  get_spotify_album: "openai/gpt-5.4-mini",
+  search_web: "openai/gpt-5.4-mini",
+  generate_txt_file: "openai/gpt-5.4-mini",
+  create_segments: "openai/gpt-5.4-mini",
+  youtube_login: "openai/gpt-5.4-mini",
+  web_deep_research: "openai/gpt-5.4-mini",
+  create_knowledge_base: "openai/gpt-5.4-mini",
+  send_email: "openai/gpt-5.4-mini",
 };
 
 // Map trigger tool -> sequence AFTER trigger