Error Handling in FastMCP Servers
48%
MCP Clients vs LLMs: Who sees the error?
Programmatic MCP clients (like FastMCP's Client) do care about the isError flag. By default, call_tool() raises a ToolError exception when isError is true. You can disable that and inspect it yourself:
result = await client.call_tool(
"my_tool",
{"param": "value"},
raise_on_error=False
)Practical MCP with FastMCP & LangChain
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