v0.54.1 - Bug fixes and performance improvements

Fixes:
- Print errors to stderr for invalid jsonschema tags in WithInputSchema
  and WithOutputSchema (#894)

Performance:
- Reduce allocations in UnmarshalContent by avoiding map[string]any (#890)

Improvements:
- Add Title and Size fields to ResourceLink
- Refactor session types to share clientInfoStore and writeJSONRPCError helper

v0.54.0 - OpenTelemetry tracing, MCP 2025-11-25 spec additions, and p…

…anic recovery hardening

Features:
- Add OpenTelemetry tracing hooks to server and client via new otel/ submodule (#856)
- Add BaseMetadata.title, Icon.theme, and Resource.size fields per MCP spec (#870, #885)
- Add 2025-11-25 sampling-with-tools support and capability sub-fields (#867, #876)

Fixes:
- Add panic recovery to session hook goroutines (#883)
- Add panic recovery to task goroutines and fix cleanup goroutine leak (#880)
- Add panic recovery to SSE message handler and stdio tool call worker (#882)
- OAuth: don't hold metadataMu across HTTP discovery (#871, #875)
- OAuth: use LATEST_PROTOCOL_VERSION in metadata discovery (#868, #874)
- Server: handle resources/subscribe and resources/unsubscribe properly (#865, #873)

Improvements:
- Refactor to use MCP method constants throughout (#878)
- Add missing godoc comments across the codebase (#877)

otel/v0.54.0 - Initial release of OpenTelemetry tracing submodule

Introduces the github.com/mark3labs/mcp-go/otel submodule providing
OpenTelemetry tracing hooks for both MCP servers and clients (#856).

Features:
- Server tracing hooks for request/response spans
- Client tracing hooks for outgoing requests
- Configurable tracer provider and span attributes
- Example integration under otel/example/

v0.53.0 - New server options, session management, and transport harde…

…ning

Features:
- Add WithStrictInputSchemaDefault server option (#853)
- Add CloseSessions method on MCPServer (#852)

Breaking Changes:
- ListPrompts and ListResources now return map[string]*ServerPrompt /
  map[string]*ServerResource (pointer values) (#855)

Fixes:
- Allow _meta on paginated requests (#854)
- ToolInputSchema inherits MarshalJSON from ToolArgumentsSchema (#858)
- Add panic recovery to transport goroutines (#861)
- Suppress closed-pipe shutdown noise on transport shutdown (#863)
- Prevent double-close panic on SSE sessions (#852)

Refactor:
- Use explicit struct literal in ListTools (#864)

v0.52.0 - Transport-agnostic Handle entry point and HTTP body leak fix

Features:
- server: add transport-agnostic Handle entry point with new exported
  HTTPRequest and HTTPResponseWriter types, enabling StreamableHTTPServer
  to be driven from non-net/http frameworks (e.g., fasthttp/fiber) without
  the buffering adaptor. ServeHTTP is now a thin wrapper around Handle.
  Backward-compatible: all existing APIs, options, and session interfaces
  unchanged. (#851, closes #611)

Fixes:
- client/transport: close response body on 404 in sendHTTP to prevent
  TCP connection / file descriptor leaks under listenForever retry loops
  when sessions are terminated. (#849)

Docs:
- README and HTTP transport guide updated with Handle usage, CanStream()
  contract, and a fasthttp adapter example.

v0.51.0 - New transports, schema validation, CORS, OAuth metadata, an…

…d iterators

Features:
- mcp: add SchemaCache for stateless/serverless deployments (#846)
- transport: add LoggingTransport wrapper for JSON-RPC tracing (#845)
- server: validate tool output against declared output schemas (#844)
- server: add opt-in CORS support to HTTP transports (#843)
- client: add Go 1.23 iterator methods (IterTools/IterResources/IterPrompts) for paginated results (#842)
- server: add OAuth Protected Resource Metadata endpoint per RFC 9728 (#841)
- transport: add CommandTransport for subprocess MCP servers (#840)
- server: opt-in input schema validation per SEP-1303 (#834)

Fixes:
- oauth: accept any 2xx token response status (#847)
- transport: stop retrying on session terminated in listenForever (#839)
- server: setTools may have resulted in empty tools (#830)
- examples: return isError for input validation instead of internal error (#838)

Docs:
- server: document OnBeforeAny/OnSuccess/OnError pairing (#848)
- clients: document IterTools/IterResources/IterPrompts iterators

v0.50.0 - Input schema validation and new list methods

Features:
- Opt-in input schema validation per SEP-1303 via WithInputSchemaValidation()
  server option (#834). When enabled, tools/call arguments are validated
  against each tool's inputSchema before the handler runs; failures are
  returned as tool execution errors so the model can self-correct.
  Compiled schemas are cached per (toolName, schemaDigest).
- Add ListPrompts and ListResources methods to the server (#831).

Dependencies:
- Add santhosh-tekuri/jsonschema/v6 for JSON Schema validation.

v0.49.0 - Add OAuth protected resource metadata discovery

Features:
- Implement RFC9728 OAuth Protected Resource Metadata discovery
- Add client helpers for extracting protected resource metadata URLs from authorization errors
- Improve OAuth handling for SSE and streamable HTTP transports

Improvements:
- Add MCP utility helpers and expand protocol/type coverage
- Improve streamable HTTP server session cleanup and test coverage

Maintenance:
- Formatting and test updates across client, server, and MCP packages

v0.48.0 - Server implementation metadata options and OAuth RFC 8707 s…

…upport

Features:
- Add WithTitle, WithDescription, WithWebsiteURL, WithIcons server options for rich implementation metadata
- Add ServerOption support to mcptest test servers
- Add RFC 8707 resource parameter to OAuth authorization, token exchange, refresh, and client registration requests

Fixes:
- Fix stdin race condition in stdio transport by serializing concurrent writes

Documentation:
- Update server basics docs with implementation metadata option examples

fix: goroutine leak and stdio child shutdown handling

Bug fixes:
- fix(transport): exit ContinuousListening goroutine on context cancellation (#790)
- Bound stdio child shutdown in Close() with graceful timeout handling (#784)