fix: CallToolResult emits spec isError; structuredContent typed as object - #49
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…ontent as object Fast-follow polish on the merged structured-output PR (#45), from the Codex review: - CallToolResult now serializes `is_error` under the MCP wire key `isError` (added to StructTypes.names). Spec-compliant clients read `isError` to detect tool failures, so previously every tool error looked like success to them. Wire-key only; the Julia field stays `is_error`. - `CallToolResult.structured_content` typed `Union{Nothing,AbstractDict}` (was effectively `Any`) -- MCP structuredContent is a JSON object; this rejects root scalars/arrays and non-serializable values at construction. - Updated the two tests that asserted the serialized `is_error` key. Suite green (499). Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
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Add the missing 0.5.0 entries (#39 feature gating, #40 e2e harness, #44 annotations, #45 structured output, #49 isError wire-key fix, #50 progress notifications), credit @samtalki's contributions, backfill [0.4.0]/[0.4.1] sections, update compare links, and set the release date. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
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Fast-follow polish on the merged structured-output PR (#45), from the Codex review of the samtalki PRs.
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is_error→isErrorwire key (the important one):CallToolResultnow serializes its error flag under the MCP spec keyisError(added toStructTypes.names). Spec-compliant clients readisErrorto detect tool failures — so until now every tool error looked like a success to them. Julia field staysis_error; only the wire key changes.structured_contenttypedUnion{Nothing,AbstractDict}(was effectivelyAny). MCPstructuredContentis a JSON object; this rejects root scalars/arrays and non-serializable values at construction time.is_errorkey (test_http,serialization).Suite green (499). No version bump — part of the unreleased 0.5.0.
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