fix(jsonschema): don't require @id in single-item MCP output schema#8343
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soyuka merged 2 commits intoJun 22, 2026
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IriConverter returns a null IRI for a non-collection McpTool/McpResource, so the serializer omits @id but the schema still required it — strict MCP clients rejected the structuredContent. Kept required for McpToolCollection members, which do get an IRI. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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What
For a single-item
McpTool/McpResourcewithstructuredContentenabled, the advertised JSON-LDoutputSchemano longer marks@idas required.@typestays required;McpToolCollectionmembers keep requiring@id.Why
A single-item MCP operation has no routed item URI, so
Mcp\Routing\IriConverter::getIriFromResource()returnsnulland the serializer omits@idfrom thestructuredContent. The schema still required@id, so a strict MCP client (validating the payload against theoutputSchemafromtools/list) rejected the response with/<root>: The required properties (@id) are missing.The fix mirrors the
IriConverternull-@idbehaviour on the schema side:Hydra\JsonSchema\SchemaFactorynow selects the existingHydraItemBaseSchemaWithoutIdbase (already used whengen_idisfalse) for non-collection MCP output schemas. AMcpToolCollectionis excluded — its members get an IRI because member normalization setsitem_uri_template— so the collection case is unaffected.