isUnauthorizedError (lib/mcp-unauthorized-error.ts)

Detects 401 unauthorized errors from MCP servers for auth state handling.

// Source: https://github.com/thunderbird/thunderbolt | License: MPL-2.0 | Copyright under Patent Claims infringed by Covered Software in the absence of | Modified files must remain under MPL-2.0
// Modifications to this file must remain under MPL-2.0.
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/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
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/**
 * True when connecting to an MCP server failed because it demands OAuth
 * authorization (HTTP 401). Without an SDK `authProvider`, `@ai-sdk/mcp`
 * rejects with the raw transport error, not a closed-connection `MCPClientError`:
 *   - `StreamableHTTPError(401, ...)` or 

... (truncated -- full source via MCP)