sequenceDiagram
 participant Client as API Block/Client
 participant ProxyRoute as /api/proxy
 participant ToolHandler as tools/index.ts
 participant ExternalAPI as External API
 
 Note over Client,ExternalAPI: User-configured timeout flow
 
 Client->>ProxyRoute: POST /api/proxy<br/>{toolId, params: {timeout: 600000}}
 Note over ProxyRoute: maxDuration = 600s<br/>(Next.js route config)
 
 ProxyRoute->>ToolHandler: executeTool(toolId, params)
 
 alt Internal Request Handler
 ToolHandler->>ToolHandler: parseTimeout(params.timeout)<br/>Returns: min(timeout, 600000ms)
 Note over ToolHandler: timeout: false<br/>signal: AbortSignal.timeout(timeoutMs)
 ToolHandler->>ExternalAPI: fetch(url, {timeout: false, signal})
 ExternalAPI-->>ToolHandler: Response (within timeout)
 ToolHandler-->>ProxyRoute: Success
 else Proxy Request Handler
 ToolHandler->>ToolHandler: parseTimeout(params.timeout)<br/>Returns: min(timeout, 600000ms)
 Note over ToolHandler: timeout: false<br/>signal: AbortSignal.timeout(timeoutMs)
 ToolHandler->>ProxyRoute: fetch(/api/proxy, {timeout: false, signal})
 ProxyRoute->>ExternalAPI: Forward request
 ExternalAPI-->>ProxyRoute: Response (within timeout)
 ProxyRoute-->>ToolHandler: Response
 ToolHandler-->>ProxyRoute: Success
 end
 
 ProxyRoute-->>Client: Response with result
 
 Note over Client,ExternalAPI: Timeout scenarios
 
 alt Timeout Exceeded
 ToolHandler->>ExternalAPI: fetch with AbortSignal
 Note over ExternalAPI: Request takes > timeoutMs
 ExternalAPI-xToolHandler: AbortError (signal timeout)
 ToolHandler-->>Client: Error: Request timed out
 end
 
 alt GET /api/proxy (Direct Proxy)
 Client->>ProxyRoute: GET /api/proxy?url=...
 Note over ProxyRoute: timeout: false<br/>NO AbortSignal!<br/>Relies only on maxDuration=600s
 ProxyRoute->>ExternalAPI: fetch(url, {timeout: false})
 ExternalAPI-->>ProxyRoute: Response
 ProxyRoute-->>Client: Response
 end