fix(mcp): inline tool schemas so inputSchema is type:object#121
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deriveSchema used jsonschema.Reflect's default, which emits a top-level
{"$ref":"#/$defs/..."} with the object schema nested in $defs. The MCP
spec requires inputSchema/outputSchema to be an object schema (type:"object"),
and clients reject the ENTIRE tools/list when any tool's top-level schema is a
$ref. Setting DoNotReference inlines the struct schema as a concrete
{"type":"object",...}.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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Problem
deriveSchema(used byMCPTool/MCPResource) marshalledjsonschema.Reflect(zero), whose default output is a top-level{"$ref":"#/$defs/<Type>"}with the actual object schema under$defs.The MCP spec requires a tool's
inputSchema/outputSchemato be an object schema withtype: "object". A top-level$refmakes MCP clients (e.g. Claude Code) reject the entiretools/listwithInvalid input: expected "object"— so one module's tools break every module's tools for that account.Fix
Use
&jsonschema.Reflector{DoNotReference: true}so the struct schema inlines as a concrete{"type":"object","properties":{...}}. Nested types still inline correctly.Impact
Any module declaring
ms.MCPTool/ms.MCPResourcenow emits spec-valid schemas; existing catalogs re-sync to valid schemas on next install.🤖 Generated with Claude Code