github.com/mark3labs/mcp-go

What's Changed

• feat(mcp,server,client): support the 2026-07-28 specification by @ezynda3 in #951

Full Changelog: v0.58.0...v1.0.0-beta.1

What's Changed

• fix(server): return 200 for HEAD requests instead of 404 by @suxiaohun in #937
• [mcp] document exported helper functions by @zbarsky-openai in #940
• fix(server): deliver request-scoped elicitation on the originating POST SSE stream by @Yusufihsangorgel in #933
• docs: bump CONTRIBUTING Go prerequisite to match go.mod (1.23 → 1.25) by @kobihikri in #929
• fix: rewrite draft-07 definitions refs when adopting them as $defs by @WilliamAGH in #950
• fix(server): flush final SSE response in handlePost by @vinayaksachdeva in #945
• Fix #943: refuse unsupported subscribe requests by @Abdullah-Builds in #946
• fix(mcp): preserve schema tags on nested fields by @ychampion in #920

New Contributors

• @zbarsky-openai made their first contribution in #940
• @kobihikri made their first contribution in #929
• @WilliamAGH made their first contribution in #950
• @vinayaksachdeva made their first contribution in #945
• @Abdullah-Builds made their first contribution in #946
• @ychampion made their first contribution in #920

Full Changelog: v0.57.0...v0.58.0

What's Changed

• fix(client): make initialized state atomic by @MitulShah1 in #936
• fix(mcp): support jsonschema_description and enum struct tags by @syf2211 in #931
• fix(streamable_http): close active sessions before Shutdown by @syf2211 in #926
• fix(client): accept Content-Type parameters on GET listening stream by @Yusufihsangorgel in #925
• fix(server): label client JSON-RPC errors by method in streamable HTTP by @zent7x in #924
• fix(mcp): unmarshal embedded resource contents by @jstar0 in #938
• feat(server): add streamable HTTP stream resumability via pluggable EventStore by @Abhinav2408 in #930
• docs(examples): fix stale struct tags in structured I/O example by @zent7x in #923
• fix(transport): concatenate multi-line SSE data fields instead of overwriting by @Yusufihsangorgel in #927
• fix: deliver server notifications to in-process transport clients by @jgangemi in #919

New Contributors

• @MitulShah1 made their first contribution in #936
• @Yusufihsangorgel made their first contribution in #925
• @zent7x made their first contribution in #924
• @jgangemi made their first contribution in #919

Full Changelog: v0.56.0...v0.57.0

What's Changed

• feat(server): add automatic DNS rebinding protection for localhost by @ezynda3 in #921
• fix(tools): preserve raw JSON for tool arguments and structuredContent by @syf2211 in #916
• fix(server): render readable ErrorKind labels in validation messages by @syf2211 in #915

Full Changelog: v0.55.1...v0.56.0

What's Changed

• fix: avoid full filter scans on call hot paths by @jstar0 in #908
• fix(client): avoid forwarding inbound request headers by @Zhang-986 in #909

New Contributors

• @Zhang-986 made their first contribution in #909

Full Changelog: v0.55.0...v0.55.1

What's Changed

• fix: enforce tool/prompt filters at call time, not just list time by @Praiseson6065 in #898
• feat(tracing): add MetaPropagator for W3C trace context via MCP _meta (SEP-414) by @QuentinBisson in #895
• feat(server): WithLogger consolidates structured logging onto *slog.Logger by @QuentinBisson in #892
• feat(otel): WithServerLogging — OTEL slog bridge for server structured logs by @QuentinBisson in #901
• mcptest: add SetSamplingHandler and SetElicitationHandler by @basilalshukaili in #902
• oauth: return error instead of (nil, nil) from getServerMetadata (#903) by @pjdurden in #904

New Contributors

• @Praiseson6065 made their first contribution in #898
• @basilalshukaili made their first contribution in #902
• @pjdurden made their first contribution in #904

Full Changelog: v0.54.1...v0.55.0

What's Changed

• fix(server): handle resources/subscribe and resources/unsubscribe (#865) by @ezynda3 in #873
• fix(oauth): use LATEST_PROTOCOL_VERSION in metadata discovery (#868) by @ezynda3 in #874
• fix(oauth): don't hold metadataMu across HTTP discovery (#871) by @ezynda3 in #875
• feat(mcp): add 2025-11-25 sampling-with-tools and capability sub-fields (#867) by @ezynda3 in #876
• refactor: use MCP method constants by @nanookclaw in #878
• docs: add missing godoc comments by @aqilaziz in #877
• fix: add panic recovery to SSE message handler and stdio tool call worker by @blackwell-systems in #882
• fix: add panic recovery to task goroutines, fix cleanup goroutine leak by @blackwell-systems in #880
• feat: add OpenTelemetry tracing hooks to server and client by @QuentinBisson in #856
• fix: add panic recovery to session hook goroutines by @blackwell-systems in #883
• feat(mcp): add BaseMetadata.title, Icon.theme, Resource.size (#870) by @ezynda3 in #885
• refactor(server): collapse client-info and writeJSONRPCError duplication by @ezynda3 in #886
• Add Title and Size to ResourceLink (match Resource / spec) by @gerami-ant in #887
• perf(mcp): reduce content unmarshal allocations by @dhimasardinata in #890
• fix(tools): print errors to stderr for invalid jsonschema tags by @jasonl4 in #894

New Contributors

• @nanookclaw made their first contribution in #878
• @aqilaziz made their first contribution in #877
• @gerami-ant made their first contribution in #887
• @dhimasardinata made their first contribution in #890
• @jasonl4 made their first contribution in #894

Full Changelog: v0.53.0...v0.54.1

What's Changed

• fix(server): handle resources/subscribe and resources/unsubscribe (#865) by @ezynda3 in #873
• fix(oauth): use LATEST_PROTOCOL_VERSION in metadata discovery (#868) by @ezynda3 in #874
• fix(oauth): don't hold metadataMu across HTTP discovery (#871) by @ezynda3 in #875
• feat(mcp): add 2025-11-25 sampling-with-tools and capability sub-fields (#867) by @ezynda3 in #876
• refactor: use MCP method constants by @nanookclaw in #878
• docs: add missing godoc comments by @aqilaziz in #877
• fix: add panic recovery to SSE message handler and stdio tool call worker by @blackwell-systems in #882
• fix: add panic recovery to task goroutines, fix cleanup goroutine leak by @blackwell-systems in #880
• feat: add OpenTelemetry tracing hooks to server and client by @QuentinBisson in #856
• fix: add panic recovery to session hook goroutines by @blackwell-systems in #883
• feat(mcp): add BaseMetadata.title, Icon.theme, Resource.size (#870) by @ezynda3 in #885

New Contributors

• @nanookclaw made their first contribution in #878
• @aqilaziz made their first contribution in #877

Full Changelog: v0.53.0...v0.54.0

What's Changed

• feat(server): add WithStrictInputSchemaDefault by @QuentinBisson in #853
• fix(server): add CloseSessions and prevent double-close panic on SSE sessions by @blackwell-systems in #852
• fix(transport): suppress closed-pipe shutdown noise by @Gujiassh in #863
• fix: add panic recovery to transport goroutines by @blackwell-systems in #861
• fix: ToolInputSchema inherits MarshalJSON (fixes #694) by @tamish-max in #858
• we should use pointers on returns for ListPrompts and ListResources by @Patryk-Stefanski in #855
• fix(mcp): allow _meta on paginated requests by @curbol in #854
• refactor(server): use explicit struct literal in ListTools by @ezynda3 in #864

New Contributors

• @QuentinBisson made their first contribution in #853
• @tamish-max made their first contribution in #858
• @curbol made their first contribution in #854

Full Changelog: v0.52.0...v0.53.0