Treat omitted MCP tool arguments as empty object#2680
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Zero-parameter tools like get_me fail when clients omit the arguments
field entirely. Default empty/missing JSON payloads to {} before
unmarshaling.
Fixes github#2587
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Problem
Zero-parameter MCP tools such as
get_mefail when a client omits theargumentsfield entirely. Some MCP clients send noargumentspayload for tools with an empty input schema, which is valid JSON-RPC but breaks server-side unmarshaling.Root cause
NewServerToolWithContextHandlerunmarshalsreq.Params.Argumentsdirectly into the handler argument struct. When the field is missing or empty,json.Unmarshalreceives nil/empty bytes and returns an error before the tool handler runs.Fix
Default nil or empty
Argumentspayloads to{}before unmarshaling. This matches the MCP expectation that tools with no required parameters can be invoked without an explicit arguments object.Testing
go test ./pkg/inventory/...Fixes #2587