fixes#573fixes#574fixes#708
- Handlers ran on `Dispatchers.IO` → now `Dispatchers.Default`,
configurable via `handlerDispatcher`.
- Reader/writer dispatcher exposed as `ioDispatcher` (default
`IODispatcher.limitedParallelism(2)`).
- Optional caller-supplied `CoroutineScope` so the pipeline isn't
detached from the caller's tree.
- `CancellationException` consistently rethrown across all pumps.
- Unbounded channels → bounded with graceful drain on close (in-flight
outbound flushed before `onClose`).
- Input `Source` now closed on natural EOF / reader error (was leaking
for non-`System.in` sources).
- Race between `start()` and `close()` fixed via 3-state CAS +
`setupComplete` barrier replacing `AtomicBoolean`.
## How Has This Been Tested?
unit and integration tests
## Breaking Changes
- Handlers default to `Dispatchers.Default` (was `Dispatchers.IO`).
Override with `handlerDispatcher = Dispatchers.IO` if your handlers
perform blocking I/O.
- `send()` suspends under back-pressure instead of buffering unbounded.
- `StdioServerTransport(input, output)` ctor is `@Deprecated` (WARNING)
in favor of `StdioServerTransport(input, output) { ... }`. Still
binary-compatible.
## Types of changes
- [x] Bug fix (non-breaking change which fixes an issue)
- [x] New feature (non-breaking change which adds functionality)
- [ ] Breaking change (fix or feature that would cause existing
functionality to change)
- [ ] Documentation update
## Checklist
- [x] I have read the [MCP
Documentation](https://modelcontextprotocol.io)
- [x] My code follows the repository's style guidelines
- [x] New and existing tests pass locally
- [x] I have added appropriate error handling
- [x] I have added or updated documentation as needed
closes#544
Replaces opaque `JsonObject?` modelling of `elicitation` with a typed
`ClientCapabilities.Elicitation` (`form`, `url`), and adds the new
`tasks` capability on both `ClientCapabilities` and `ServerCapabilities`
(with `list`, `cancel`, per-request-type augmentation). Wires capability
assertions for `tasks/*` methods and `notifications/tasks/status` into
`Client` and `ServerSession`
## How Has This Been Tested?
unit tests
## Breaking Changes
yes
now elicitation is a specific class in capabilities
## Types of changes
- [ ] Bug fix (non-breaking change which fixes an issue)
- [x] New feature (non-breaking change which adds functionality)
- [x] Breaking change (fix or feature that would cause existing
functionality to change)
- [ ] Documentation update
## Checklist
- [x] I have read the [MCP
Documentation](https://modelcontextprotocol.io)
- [x] My code follows the repository's style guidelines
- [x] New and existing tests pass locally
- [x] I have added appropriate error handling
- [x] I have added or updated documentation as needed
Add `DnsRebindingProtection` Ktor route-scoped plugin and enable it by
default across all http transports
## Motivation and Context
DNS rebinding protection was disabled by default
(`enableDnsRebindingProtection = false`), and sse endpoints
(`Route.mcp()`) had zero protection. Same vulnerability as typescript
sdk
[GHSA-w48q-cv73-mx4w](https://github.com/modelcontextprotocol/typescript-sdk/security/advisories/GHSA-w48q-cv73-mx4w)
## How Has This Been Tested?
all tests pass
## Breaking Changes
- `Route.mcp()`, `Application.mcp()` signatures changed (new
`enableDnsRebindingProtection`, `allowedHosts`, `allowedOrigins`
params), binary incompatible on JVM
- `enableDnsRebindingProtection` default changed from `false` to `true`
on `mcpStreamableHttp`/`mcpStatelessStreamableHttp`
- Default allowed hosts: `localhost`, `127.0.0.1`, `[::1]` — opt out
with `enableDnsRebindingProtection = false`
- Host validation is now port-agnostic (matches ts sdk)
- Origin validation now allows missing `Origin` header (non-browser
clients)
- `Configuration.enableDnsRebindingProtection`, `.allowedHosts`,
`.allowedOrigins` deprecated in favor of the plugin
## Types of changes
- [x] Bug fix (non-breaking change which fixes an issue)
- [x] New feature (non-breaking change which adds functionality)
- [x] Breaking change (fix or feature that would cause existing
functionality to change)
- [ ] Documentation update
## Checklist
- [x] I have read the [MCP
Documentation](https://modelcontextprotocol.io)
- [x] My code follows the repository's style guidelines
- [x] New and existing tests pass locally
- [x] I have added appropriate error handling
- [x] I have added or updated documentation as needed
Migrate detekt to a convention plugin in `buildSrc`, switch the project
to a fully explicit YAML config (`buildUponDefaultConfig = false`), fix
the real findings that this stricter setup revealed, and remove
`@Suppress` annotations that became unnecessary after the rule changes.
## Motivation and Context
- Explicit visibility into the rule set
- Lock against detekt version upgrades
## Breaking Changes
None
## Types of changes
- [x] Bug fix (non-breaking change which fixes an issue)
- [ ] New feature (non-breaking change which adds functionality)
- [ ] Breaking change (fix or feature that would cause existing
functionality to change)
- [x] Documentation update
## Checklist
- [x] I have read the [MCP
Documentation](https://modelcontextprotocol.io)
- [x] My code follows the repository's style guidelines
- [x] New and existing tests pass locally
- [x] I have added appropriate error handling
- [x] I have added or updated documentation as needed
## Motivation and Context
When a GET SSE stream disconnects and the client reconnects on the same
session, the new GET is silently rejected because the previous stream's
`STANDALONE_SSE_STREAM_ID` entry in `streamsMapping` hasn't been cleaned
up yet. Cleanup via `invokeOnCompletion` is asynchronous — there is a
race window where the stale entry persists and blocks reconnection.
Additionally, Ktor's `sse {}` handler commits 200 OK headers before
`handleGetRequest` runs, so the intended
`call.reject(HttpStatusCode.Conflict, ...)` cannot change the
already-committed HTTP status. On all tested engines (test host, CIO,
Netty), clients receive a 200 OK with an immediately-closed empty SSE
stream rather than a 409 Conflict. Server-side `CallLogging` reports 409
(from the response object, not the wire status), which is misleading.
### What this PR does
1. **Explicitly closes the old SSE session** before establishing a new
stream. If the old session is already dead, `close()` is a no-op. This
is the synchronous cleanup that the async `invokeOnCompletion` couldn't
provide.
2. **Replaces `invokeOnCompletion` with `try/finally`** around
`awaitCancellation()` — cleanup runs during cancellation propagation
(earlier in the lifecycle) rather than after job completion. An identity
check (`=== newContext`) ensures only this stream's entry is removed,
not a replacement's.
3. **Adds identity-based removal in `emitOnStream`** — a failed `send()`
on an old stream can no longer accidentally evict the new stream's
mapping.
4. **Rethrows `CancellationException`** instead of swallowing it,
preserving structured concurrency.
The TypeScript reference implementation avoids this race via synchronous
`ReadableStream.cancel()` cleanup. The Kotlin coroutine equivalent
(`invokeOnCompletion`) is inherently async. The Go SDK uses `defer
stream.release()` under a mutex for the same reason. The Java SDK uses
unconditional `AtomicReference.set()` replacement with
`compareAndExchange` on close.
Fixes#715
## How Has This Been Tested?
All tests run against latest `main` (`bf8dc6d`). ktlint and detekt pass
clean.
- 2 new unit tests (Ktor test host): reconnect after disconnect,
concurrent stream takeover
- 2 new integration tests (real CIO embedded server): same scenarios
over real HTTP
- Manual verification against a live Ktor+Netty MCP server (curl):
confirmed 200 OK on the wire with immediately-closed stream on reconnect
(pre-fix), live stream on reconnect (post-fix)
- All existing server unit tests pass (76 total)
- All existing integration tests pass (306 total)
## Breaking Changes
The server no longer returns 409 Conflict for a second GET SSE stream on
the same session. Instead, the old stream is explicitly closed and the
new stream takes over. The 409 was already unreachable as an HTTP status
— Ktor's `sse {}` handler commits 200 OK before the transport handler
runs on all tested engines (test host, CIO, Netty), so clients never
received 409 on the wire.
## Types of changes
- [x] Bug fix (non-breaking change which fixes an issue)
- [ ] New feature (non-breaking change which adds functionality)
- [ ] Breaking change (fix or feature that would cause existing
functionality to change)
- [ ] Documentation update
## Checklist
- [x] I have read the [MCP
Documentation](https://modelcontextprotocol.io)
- [x] My code follows the repository's style guidelines
- [x] New and existing tests pass locally
- [x] I have added appropriate error handling
- [x] I have added or updated documentation as needed
## Additional context
This bug likely became reachable after #681 (April 10) fixed the Netty
`appendSseHeaders` crash that previously prevented GET SSE from working
at all on Netty.
Cross-SDK comparison of how each SDK handles a second GET SSE on the
same session:
| SDK | Behavior | Cleanup mechanism | Stale mapping bug? |
|-----|----------|-------------------|-------------------|
| TypeScript (reference) | 409 Conflict | Synchronous
`ReadableStream.cancel()` | No |
| Go | 409 Conflict | `defer stream.release()` under mutex | No |
| Java | Replaces (no 409) | `AtomicReference.set()` +
`compareAndExchange` on close | No |
| C# | 400 Bad Request | Boolean flag, never reset (no reconnect
support) | No |
| Kotlin (before fix) | 409 (unreachable on wire) | Async
`invokeOnCompletion` | **Yes** |
| Kotlin (this PR) | Closes old + replaces | `try/finally` +
identity-based removal | No |
---------
Co-authored-by: devcrocod <devcrocod@gmail.com>
Implements SEP-1577 sampling With tools
closes#409
## How Has This Been Tested?
unit + integration
## Breaking Changes
- binary changes
- MediaContent -> SamplingMessageContent
-
## Types of changes
- [ ] Bug fix (non-breaking change which fixes an issue)
- [x] New feature (non-breaking change which adds functionality)
- [x] Breaking change (fix or feature that would cause existing
functionality to change)
- [ ] Documentation update
## Checklist
- [x] I have read the [MCP
Documentation](https://modelcontextprotocol.io)
- [x] My code follows the repository's style guidelines
- [x] New and existing tests pass locally
- [x] I have added appropriate error handling
- [x] I have added or updated documentation as needed
fixes#242
## How Has This Been Tested?
new and existing tests pass
## Breaking Changes
none
## Types of changes
- [x] Bug fix (non-breaking change which fixes an issue)
- [ ] New feature (non-breaking change which adds functionality)
- [ ] Breaking change (fix or feature that would cause existing
functionality to change)
- [ ] Documentation update
## Checklist
- [x] I have read the [MCP
Documentation](https://modelcontextprotocol.io)
- [x] My code follows the repository's style guidelines
- [x] New and existing tests pass locally
- [x] I have added appropriate error handling
- [x] I have added or updated documentation as needed
Validate `mcp-protocol-version` HTTP header during `InitializeRequest`
Fix `DEFAULT_NEGOTIATED_PROTOCOL_VERSION` to match the spec
fixes#547
## How Has This Been Tested?
Updated existing test (removed TODO referencing #547) to verify init
request
## Breaking Changes
none
## Types of changes
- [x] Bug fix (non-breaking change which fixes an issue)
- [ ] New feature (non-breaking change which adds functionality)
- [ ] Breaking change (fix or feature that would cause existing
functionality to change)
- [ ] Documentation update
## Checklist
- [x] I have read the [MCP
Documentation](https://modelcontextprotocol.io)
- [x] My code follows the repository's style guidelines
- [x] New and existing tests pass locally
- [x] I have added appropriate error handling
- [x] I have added or updated documentation as needed
Add warn-only validation for tool names at registration time, following
the MCP tool naming standard (SEP-986)
closes#417
## How Has This Been Tested?
unit tests
## Breaking Changes
none
## Types of changes
- [ ] Bug fix (non-breaking change which fixes an issue)
- [x] New feature (non-breaking change which adds functionality)
- [ ] Breaking change (fix or feature that would cause existing
functionality to change)
- [ ] Documentation update
## Checklist
- [x] I have read the [MCP
Documentation](https://modelcontextprotocol.io)
- [x] My code follows the repository's style guidelines
- [x] New and existing tests pass locally
- [x] I have added appropriate error handling
- [x] I have added or updated documentation as needed
`appendSseHeaders()` was called inside Ktor's `sse {}` block where
response headers are already committed. On Netty this throws
`UnsupportedOperationException`, killing the SSE stream and causing the
client to retry in a loop
## How Has This Been Tested?
unit, simple-streamable-server sample
## Breaking Changes
none
## Types of changes
- [x] Bug fix (non-breaking change which fixes an issue)
- [ ] New feature (non-breaking change which adds functionality)
- [ ] Breaking change (fix or feature that would cause existing
functionality to change)
- [ ] Documentation update
## Checklist
- [x] I have read the [MCP
Documentation](https://modelcontextprotocol.io)
- [x] My code follows the repository's style guidelines
- [x] New and existing tests pass locally
- [x ] I have added appropriate error handling
- [ x] I have added or updated documentation as needed
- enable rule for checking undocumented public api
- add kdoc skill
## How Has This Been Tested?
./gradlew detekt
## Breaking Changes
none
## Types of changes
- [ ] Bug fix (non-breaking change which fixes an issue)
- [ ] New feature (non-breaking change which adds functionality)
- [ ] Breaking change (fix or feature that would cause existing
functionality to change)
- [x] Documentation update
## Checklist
- [x] I have read the [MCP
Documentation](https://modelcontextprotocol.io)
- [x] My code follows the repository's style guidelines
- [x] New and existing tests pass locally
- [ ] I have added appropriate error handling
- [x] I have added or updated documentation as needed
---------
Co-authored-by: Konstantin Pavlov <1517853+kpavlov@users.noreply.github.com>
closes#546
## How Has This Been Tested?
unit
## Breaking Changes
none
## Types of changes
- [ ] Bug fix (non-breaking change which fixes an issue)
- [x] New feature (non-breaking change which adds functionality)
- [ ] Breaking change (fix or feature that would cause existing
functionality to change)
- [ ] Documentation update
## Checklist
- [x] I have read the [MCP
Documentation](https://modelcontextprotocol.io)
- [x] My code follows the repository's style guidelines
- [x] New and existing tests pass locally
- [ ] I have added appropriate error handling
- [ ] I have added or updated documentation as needed
Users currently must manually `install(ContentNegotiation) {
json(McpJson) }` before calling `mcp()`,
`mcpStreamableHttp()`, or `mcpStatelessStreamableHttp()`. Forgetting
this or using the default `json()`
instead of `json(McpJson)` causes silent serialization failures at
runtime (e.g., explicit null fields in JSON-RPC
responses). This PR makes the SDK install it automatically.
Fixes#664
## Changes
- **Core feature** — `mcp()`, `mcpStreamableHttp()`, and
`mcpStatelessStreamableHttp()` now auto-install `ContentNegotiation`
configured with `McpJson`. If the user already installed
`ContentNegotiation`, a warning is logged instead of crashing with
`DuplicatePluginException`.
- **`KtorServerHelpers.kt`** (new) — `installMcpContentNegotiation()`
internal helper with `pluginOrNull` guard and warning
- **`KtorServer.kt`** — calls the helper from all three entry points
- **`build.gradle.kts`** — adds `ktor-server-content-negotiation` and
`ktor-serialization` as `implementation` deps to `kotlin-sdk-server`
- **Removed manual installs** from `ConformanceServer.kt` and
`AbstractStreamableHttpIntegrationTest.kt`.
- **Test infrastructure** — replaced `slf4j-simple` with Logback and use
`ListAppender` (`LogCapture` utility) for deterministic log assertion.
Added `logback-test.xml` matching previous log levels.
- **`StreamableHttpServerConfigurationTest.kt`** (new) — verifies the
warning for all three entry points: `mcpStreamableHttp`,
`mcpStatelessStreamableHttp`, and `mcp` (SSE).
- **README.md** — removed manual `ContentNegotiation` boilerplate from
examples, documented automatic installation, added CORS configuration
snippet for browser-based clients.
- **CI** — added `ktlintCheck` to the Linux build matrix job.
## How Has This Been Tested?
Unit/integration tests. Conformance tests updated
## Breaking Changes
No
## Types of changes
- [x] Bug fix (non-breaking change which fixes an issue)
- [x] New feature (non-breaking change which adds functionality)
- [ ] Breaking change (fix or feature that would cause existing
functionality to change)
- [x] Documentation update
## Checklist
- [x] I have read the [MCP
Documentation](https://modelcontextprotocol.io)
- [x] My code follows the repository's style guidelines
- [x] New and existing tests pass locally
- [x] I have added appropriate error handling
- [x] I have added or updated documentation as needed
## Summary
Add `maxRequestBodySize` parameter to
`StreamableHttpServerTransport.Configuration`, allowing consumers to set
a custom request body size limit lower than the default 4 MB.
- Add `maxRequestBodySize: Long` property to `Configuration` with a
default of 4 MB (`4,194,304` bytes)
- Replace hardcoded `MAXIMUM_MESSAGE_SIZE` constant with the
configurable value in `parseBody()`
- Use `Long` for content-length comparison to avoid `Int` overflow on
large values
## Motivation and Context
Closes#521
The `StreamableHttpServerTransport` has a hardcoded 4 MB request body
limit. Consumers who need a lower limit currently have to manually count
the request payload size before passing it to the SDK. This change makes
the limit configurable via `Configuration`.
## How Has This Been Tested?
- Existing unit tests continue to pass (default 4 MB behavior unchanged)
- Added `POST with custom max request body size rejects oversized
payload` — verifies `PayloadTooLarge` is returned for payloads exceeding
the custom limit
- Added `POST at exactly custom max request body size is not rejected as
payload too large` — verifies payloads at exactly the limit are not
rejected by the size check
```bash
./gradlew :kotlin-sdk-server:jvmTest --tests "*.StreamableHttpServerTransportTest"
```
## Breaking Changes
None. The new parameter has a default value matching the previous
hardcoded limit.
## Types of changes
- [ ] Bug fix (non-breaking change which fixes an issue)
- [x] New feature (non-breaking change which adds functionality)
- [ ] Breaking change (fix or feature that would cause existing
functionality to change)
- [ ] Documentation update
## Checklist
- [x] I have read the [MCP
Documentation](https://modelcontextprotocol.io)
- [x] My code follows the repository's style guidelines
- [x] New and existing tests pass locally
- [x] I have added appropriate error handling
- [x] I have added or updated documentation as needed
Add URL mode elicitation support and typed `PrimitiveSchemaDefinition`
hierarchy to align with MCP specification 2025-11-25
closes#540
## How Has This Been Tested?
unit/integration/conformance
## Breaking Changes
- `ElicitRequestParams` changed from `data class` to `sealed interface`.
A deprecated factory function preserves source compatibility for
`ElicitRequestParams(message, requestedSchema)`.
- `RequestedSchema.properties` changed from `JsonObject` to `Map<String,
PrimitiveSchemaDefinition>`.
- `ElicitRequest.requestedSchema` is deprecated, use `(params as
ElicitRequestFormParams).requestedSchema`.
## Types of changes
- [ ] Bug fix (non-breaking change which fixes an issue)
- [x] New feature (non-breaking change which adds functionality)
- [x] Breaking change (fix or feature that would cause existing
functionality to change)
- [ ] Documentation update
## Checklist
- [x] I have read the [MCP
Documentation](https://modelcontextprotocol.io)
- [x] My code follows the repository's style guidelines
- [x] New and existing tests pass locally
- [x] I have added appropriate error handling
- [x] I have added or updated documentation as needed
`ServerSession.handleInitialize()` now rejects duplicate `initialize`
requests with `INVALID_REQUEST` (-32600) error. `clientCapabilities` and
`clientVersion` changed from `var` to `AtomicRef`-backed `val`, with
atomic `compareAndSet(null, ...)` serving as both the guard and the
write
## How Has This Been Tested?
second `initialize` returns error, original capabilities preserved
## Breaking Changes
none
## Types of changes
- [x] Bug fix (non-breaking change which fixes an issue)
- [ ] New feature (non-breaking change which adds functionality)
- [ ] Breaking change (fix or feature that would cause existing
functionality to change)
- [ ] Documentation update
## Checklist
- [x] I have read the [MCP
Documentation](https://modelcontextprotocol.io)
- [x] My code follows the repository's style guidelines
- [x] New and existing tests pass locally
- [x] I have added appropriate error handling
- [x] I have added or updated documentation as needed
## Additional context
<!-- Add any other context, implementation notes, or design decisions
-->
Remove all deprecation with error level
## Motivation and Context
next minor release
## How Has This Been Tested?
-
## Breaking Changes
Removing it is a binary-incompatible change
## Types of changes
- [ ] Bug fix (non-breaking change which fixes an issue)
- [ ] New feature (non-breaking change which adds functionality)
- [ ] Breaking change (fix or feature that would cause existing
functionality to change)
- [ ] Documentation update
## Checklist
- [x] I have read the [MCP
Documentation](https://modelcontextprotocol.io)
- [x] My code follows the repository's style guidelines
- [x] New and existing tests pass locally
- [x] I have added appropriate error handling
- [x] I have added or updated documentation as needed
## Changes
- fix(server): keep SSE connection open until explicitly cancelled
- conformance: add logging to test_tool_with_logging and update
troubleshooting documentation
- chore(conformance): remove 5 passing server tests from conformance
baselines:
- tools-call-with-logging
- tools-call-with-progress
- tools-call-sampling
- tools-call-elicitation
- elicitation-sep1034-defaults
## Motivation and Context
Two bugs in StreamableHttpServerTransport caused server-to-client
notifications (e.g. notifications/message during tool calls) to be
silently dropped.
**Bug 1 — GET SSE stream closed immediately**
`handleGetRequest` rejected GET requests with 405 when
`enableJsonResponse = true` (which `mcpStreamableHttp` always sets).
Since the Ktor `sse {}` handler commits response headers before the body
runs, the reject failed silently and the function returned, causing Ktor
to close the SSE stream. There was also no `awaitCancellation()` to keep
the connection alive.
**Bug 2 — Notifications discarded in JSON mode**
In `send()`, notifications with a relatedRequestId entered the
POST-stream path but hit `if (!isTerminated) return` without being
forwarded anywhere.
**Fix**
- Remove the enableJsonResponse guard from handleGetRequest. The GET SSE
stream is an always-required notification channel, orthogonal to how
POST responses are delivered.
- Add `awaitCancellation()` to keep the GET SSE connection open until
the client disconnects or the transport closes.
- In `send()`, route notifications with a relatedRequestId to the
standalone GET SSE stream when `enableJsonResponse = true`.
## How Has This Been Tested?
Verified against the MCP conformance test suite — the
ToolsCallWithLogging scenario now passes. ngrep confirms the `GET /mcp`
stream stays open and `notifications/message` events arrive before the
`tools/call` response.
## Breaking Changes
<!-- Will users need to update their code or configurations? -->
## Types of changes
<!-- What types of changes does your code introduce? Put an `x` in all
the boxes that apply: -->
- [x] Bug fix (non-breaking change which fixes an issue)
- [ ] New feature (non-breaking change which adds functionality)
- [ ] Breaking change (fix or feature that would cause existing
functionality to change)
- [ ] Documentation update
## Checklist
<!-- Go over all the following points, and put an `x` in all the boxes
that apply. -->
- [x] I have read the [MCP
Documentation](https://modelcontextprotocol.io)
- [x] My code follows the repository's style guidelines
- [ ] New and existing tests pass locally
- [ ] I have added appropriate error handling
- [ ] I have added or updated documentation as needed
## Additional context
Fixes#587
Requires #585 to be merged first.
---------
Co-authored-by: devcrocod <devcrocod@gmail.com>
Adds a comprehensive conformance test suite for the Kotlin MCP SDK,
covering core protocol operations, tool calls, elicitation, resources,
prompts, and 20 OAuth/auth scenarios
- Conformance server and client implementations
- OAuth/auth test scenarios: JWT, authorization code flow, client
credentials, PKCE, scope handling, cross-app access, client registration
- CI workflow
- Baseline file for tracking expected failures
- Shell script
fixes:
- #592
- #593
- #596
## Remaining known failures (tracked issues, will be fixed directly in
`main`)
- [x] `tools-call-with-logging`, `tools-call-with-progress`,
`tools-call-sampling`, `tools-call-elicitation`,
`elicitation-sep1034-defaults`- see #599,
- [x] `elicitation-sep1330-enums` - #587#600
- [x] `initialize` - #588
- [x] `tools_call`, `auth/scope-step-up`, `auth/scope-retry-limit` -
#589
- [ ] `elicitation-sep1034-client-defaults` - #414
- [x] `sse-retry` - #590
- [ ] `resources-templates-read` - #591
## Breaking Changes
from #596
- `StreamableHttpClientTransport` and
`mcpStreamableHttp`/`mcpStreamableHttpTransport`: old constructors
accepting `Duration` timeout are now `@Deprecated` — use the new
overloads with `ReconnectionOptions` instead
- `StreamableHttpClientTransport.close()` no longer calls
`terminateSession()` automatically
## Types of changes
- [x] Bug fix (non-breaking change which fixes an issue)
- [x] New feature (non-breaking change which adds functionality)
- [x] Breaking change (fix or feature that would cause existing
functionality to change)
- [ ] Documentation update
## Checklist
- [x] I have read the [MCP
Documentation](https://modelcontextprotocol.io)
- [x] My code follows the repository's style guidelines
- [x] New and existing tests pass locally
- [x] I have added appropriate error handling
- [x] I have added or updated documentation as needed
---------
Co-authored-by: Konstantin Pavlov <1517853+kpavlov@users.noreply.github.com>
closes#543
## How Has This Been Tested?
unit
## Breaking Changes
binary compatibility in the Tool class
## Types of changes
- [ ] Bug fix (non-breaking change which fixes an issue)
- [x] New feature (non-breaking change which adds functionality)
- [ ] Breaking change (fix or feature that would cause existing
functionality to change)
- [ ] Documentation update
## Checklist
- [x] I have read the [MCP
Documentation](https://modelcontextprotocol.io)
- [x] My code follows the repository's style guidelines
- [x] New and existing tests pass locally
- [ ] I have added appropriate error handling
- [ ] I have added or updated documentation as needed
---------
Co-authored-by: Konstantin Pavlov <1517853+kpavlov@users.noreply.github.com>
## Rethrow CancellationException in StdioServerTransport, fix ReadBuffer
### Changes
1. StdioServerTransport
- Replace generic `Throwable` catches with specific
`CancellationException` and `Exception` for clarity and correctness.
**breaking change** `Throwable` is not handled any more!
- Refactor launching jobs to separate methods
- Introduce `READ_BUFFER_SIZE` constant to replace inline buffer size
literals.
- Add suppress annotations for clearer intent and constructor
documentation for better usability.
- Extend StdioServerTransportTest
2. ReadBuffer
Previously, readMessage() returned null after consuming an unparseable
line even when more complete lines existed in the buffer. This caused
valid messages following a bad line in the same chunk to be silently
dropped until the next chunk arrived (or forever, in tests).
Fix the loop so null means only "no complete line available", not
"encountered a parse failure". Blank/whitespace-only lines are now
silently skipped via isBlank() rather than forwarded to the deserializer
and logged as errors.
Refactor the method into three focused helpers:
- readMessage() — outer loop over lines
- readLine() — consume the next newline-delimited line from the buffer
- tryRecover() — attempt deserialization from the first '{' onward
3. Add utility method `runIntegrationTest` for integration testing
(`runBlocking` + `withTimeout`). Use it in StdioServerTransportTest
4. Store processing Job reference and `calcelAndJoin()` it on close.
Partially addressing #574
## Motivation and Context
See #575, #564, #242
## How Has This Been Tested?
Unit test added
## Breaking Changes
Semantic change: `Throwable` and CancellationException are not handled
any more!
## Types of changes
- [x] Bug fix (non-breaking change which fixes an issue)
- [ ] New feature (non-breaking change which adds functionality)
- [ ] Breaking change (fix or feature that would cause existing
functionality to change)
- [ ] Documentation update
## Checklist
<!-- Go over all the following points, and put an `x` in all the boxes
that apply. -->
- [x] I have read the [MCP
Documentation](https://modelcontextprotocol.io)
- [x] My code follows the repository's style guidelines
- [x] New and existing tests pass locally
- [ ] I have added appropriate error handling
- [ ] I have added or updated documentation as needed
## Additional context
<!-- Add any other context, implementation notes, or design decisions
-->
## Introduce Configuration class for StreamableHttpServerTransport
Replace the six-parameter flat constructor of
`StreamableHttpServerTransport` with a typed `Configuration` class. This
improves API ergonomics, enables structural equality and copy(), and
provides a stable extension point for future options without further
breaking the constructor signature.
### Changes:
- Add `Configuration` as a public class nested directly on
`StreamableHttpServerTransport`, with `enableJsonResponse` as the first
parameter (most commonly set)
- Change the primary constructor to accept `Configuration`.
- Rename `retryIntervalMillis: Long?` to `retryInterval: Duration?` in
Configuration, aligning with Kotlin's type-safe time API
- Deprecate the old flat constructor with a compatibility bridge
- Update KotlinTestBase integration test to use the new constructor
- Enable test
AbstractResourceIntegrationTest.testSubscribeAndUnsubscribe() since #249
is closed
## Motivation and Context
The current StreamableHttpServerTransport API cannot be easily extended:
adding more parameters would be a breaking change. But this is already
needed for #521.
This PR is a prerequisite for #535
## How Has This Been Tested?
Regression tests
## Breaking Changes
No. Current StreamableHttpServerTransport constructor was deprecated
## Types of changes
<!-- What types of changes does your code introduce? Put an `x` in all
the boxes that apply: -->
- [ ] Bug fix (non-breaking change which fixes an issue)
- [x] New feature (non-breaking change which adds functionality)
- [ ] Breaking change (fix or feature that would cause existing
functionality to change)
- [ ] Documentation update
## Checklist
<!-- Go over all the following points, and put an `x` in all the boxes
that apply. -->
- [x] I have read the [MCP
Documentation](https://modelcontextprotocol.io)
- [x] My code follows the repository's style guidelines
- [x] New and existing tests pass locally
- [ ] I have added appropriate error handling
- [ ] I have added or updated documentation as needed
## Motivation and Context
Adds a `ClientConnection` context receiver to server call handlers,
which provides access to the client communication channel. This is
necessary to allow tools to send notifications, logging, elicitations,
etc.
Supersedes https://github.com/modelcontextprotocol/kotlin-sdk/pull/144,
discussed in
https://github.com/modelcontextprotocol/kotlin-sdk/issues/295.
## How Has This Been Tested?
With the added integration test.
## Breaking Changes
It breaks binary compatibility and breaks source compatibility for tool
handlers that already use `this`.
If you care a lot about maintaining compatibility, I could add some
overloads to ease the transition. But the new methods would likely need
to be named differently for resolution.
Future compatibility should be easier to maintain - `Context` is an
interface (with experimental opt-in subclassing), so new fields can be
added without breaking compatibility. Different types could also be
introduced for different handles without breaking compatibility, as long
as they extend `ClientConnection`.
## Types of changes
<!-- What types of changes does your code introduce? Put an `x` in all
the boxes that apply: -->
- [ ] Bug fix (non-breaking change which fixes an issue)
- [x] New feature (non-breaking change which adds functionality)
- [x] Breaking change (fix or feature that would cause existing
functionality to change)
- [ ] Documentation update
## Checklist
<!-- Go over all the following points, and put an `x` in all the boxes
that apply. -->
- [x] I have read the [MCP
Documentation](https://modelcontextprotocol.io)
- [x] My code follows the repository's style guidelines
- [x] New and existing tests pass locally
- [x] I have added appropriate error handling
- [x] I have added or updated documentation as needed
## Additional context
<!-- Add any other context, implementation notes, or design decisions
-->
---------
Co-authored-by: Konstantin Pavlov <1517853+kpavlov@users.noreply.github.com>
# Migrate Ktor extension functions from `Routing` to `Route` (#237)
- Replaced `Routing` with `Route` in MCP-related functions for better
composability in nested contexts.
- Updated tests to verify compatibility with nested routes and subpaths.
- Deprecated legacy signatures and removed redundant overloads.
## How Has This Been Tested?
Unit test
## Breaking Changes
`Routing.mcp(...) `extension was replaced with `Route.mcp(...)`
## Types of changes
- [X] Bug fix (non-breaking change which fixes an issue)
- [ ] New feature (non-breaking change which adds functionality)
- [x] Breaking change (fix or feature that would cause existing
functionality to change)
- [ ] Documentation update
## Checklist
<!-- Go over all the following points, and put an `x` in all the boxes
that apply. -->
- [x] I have read the [MCP
Documentation](https://modelcontextprotocol.io)
- [x] My code follows the repository's style guidelines
- [ ] New and existing tests pass locally
- [ ] I have added appropriate error handling
- [ ] I have added or updated documentation as needed
## Additional context
Based on #314 by @IainHull but that PR is too outdated.
# Detekt setup hardeing; address some issues
- Address some detekt findings: missing KDocs, formatting, use `check*`
& `orEmpty()``
- Remove unnecessary KDoc comments from deprecated classes in `types.kt`
- Add Detekt baseline XML files for all modules
- Enforce stricter Detekt rules by setting `failOnSeverity` from `None`
to `Error`
## Motivation and Context
Detekt is not actually failing the build on violations. This PR is
enabling Detekt to fail on errors. Baseline fines added for historical
issues. Follow-up for #501
## How Has This Been Tested?
Regressions
## Breaking Changes
No breaking changes.
## Types of changes
<!-- What types of changes does your code introduce? Put an `x` in all
the boxes that apply: -->
- [ ] Bug fix (non-breaking change which fixes an issue)
- [ ] Refactoring
- [ ] New feature (non-breaking change which adds functionality)
- [ ] Breaking change (fix or feature that would cause existing
functionality to change)
- [x] Documentation update
## Checklist
<!-- Go over all the following points, and put an `x` in all the boxes
that apply. -->
- [x] I have read the [MCP
Documentation](https://modelcontextprotocol.io)
- [x] My code follows the repository's style guidelines
- [x] New and existing tests pass locally
- [ ] I have added appropriate error handling
- [ ] I have added or updated documentation as needed
## refactor: Introduce AbstractClientTransport and simplify client
transport lifecycle
This PR unifies state management logic across client transports, except
for the websocket transport, as it needs more refactoring first and is
not the primary transport.
- Introduce `AbstractClientTransport` as base class for other client
transports.
- Migrate to `ClientTransportState` states with state machine,
streamline state management.
- Ensure proper cleanup and error handling consistency across transport
implementations.
- Add unit tests to validate `AbstractClientTransport` behavior and
state transitions.
- Update related documentation and API contract.
- Make sure `onClose` callback is called at most once
- fix
[StreamableHttpClientTransportTest.kt](https://github.com/modelcontextprotocol/kotlin-sdk/pull/516/changes#diff-b9fe8891d08a492448a7ed2dc782151c6a915ae1403a4d70c2034c6062c84cb5)
to throw `McpException` on connect when received invalid Json
## Motivation and Context
Unify lifecycle handling and eliminate duplication in client Transport
implementations.
## How Has This Been Tested?
Unit test, regression tests
## Breaking Changes
- `onClose` callback is now called only once
- send(...) will throw McpException with message "Transport is not
ready" when `ClientTransportState != Operational`
## Types of changes
- [ ] Bug fix (non-breaking change which fixes an issue)
- [x] Refactoring
- [ ] New feature (non-breaking change which adds functionality)
- [x] Breaking change (fix or feature that would cause existing
functionality to change)
- [ ] Documentation update
## Checklist
<!-- Go over all the following points, and put an `x` in all the boxes
that apply. -->
- [x] I have read the [MCP
Documentation](https://modelcontextprotocol.io)
- [x] My code follows the repository's style guidelines
- [ ] New and existing tests pass locally
- [ ] I have added appropriate error handling
- [ ] I have added or updated documentation as needed
## Additional context
See #517
## Motivation and Context
Adds Ktor extensions for streaming data over the server-side HTTP
transport
## How Has This Been Tested?
Integration test
## Breaking Changes
-
## Types of changes
- [ ] Bug fix (non-breaking change which fixes an issue)
- [x] New feature (non-breaking change which adds functionality)
- [ ] Breaking change (fix or feature that would cause existing
functionality to change)
- [ ] Documentation update
## Checklist
- [x] I have read the [MCP
Documentation](https://modelcontextprotocol.io)
- [x] My code follows the repository's style guidelines
- [x] New and existing tests pass locally
- [x] I have added appropriate error handling
- [x] I have added or updated documentation as needed
#162
## Motivation and Context
- update readme
- add more snippets
- add knit
## How Has This Been Tested?
knit on CI
## Breaking Changes
None
## Types of changes
- [ ] Bug fix (non-breaking change which fixes an issue)
- [ ] New feature (non-breaking change which adds functionality)
- [ ] Breaking change (fix or feature that would cause existing
functionality to change)
- [x] Documentation update
## Checklist
- [x] I have read the [MCP
Documentation](https://modelcontextprotocol.io)
- [x] My code follows the repository's style guidelines
- [x] New and existing tests pass locally
- [ ] I have added appropriate error handling
- [x] I have added or updated documentation as needed
---------
Co-authored-by: devcrocod <devcrocod@gmail.com>
Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
- increase the deprecation level
- remove tests that use deprecated objects with deprecation level =
error
## Motivation and Context
deprecation lifecycle
## How Has This Been Tested?
-
## Breaking Changes
-
## Types of changes
- [ ] Bug fix (non-breaking change which fixes an issue)
- [ ] New feature (non-breaking change which adds functionality)
- [ ] Breaking change (fix or feature that would cause existing
functionality to change)
- [ ] Documentation update
## Checklist
- [x] I have read the [MCP
Documentation](https://modelcontextprotocol.io)
- [x] My code follows the repository's style guidelines
- [x] New and existing tests pass locally
- [ ] I have added appropriate error handling
- [ ] I have added or updated documentation as needed
- generate detekt config
- enable several rules
- disable ktlint backing property check
## Motivation and Context
Centralized control of detekt rules. Using detekt 2 configuration
## How Has This Been Tested?
locally
## Breaking Changes
-
## Types of changes
- [ ] Bug fix (non-breaking change which fixes an issue)
- [ ] New feature (non-breaking change which adds functionality)
- [ ] Breaking change (fix or feature that would cause existing
functionality to change)
- [ ] Documentation update
## Checklist
- [x] I have read the [MCP
Documentation](https://modelcontextprotocol.io)
- [x] My code follows the repository's style guidelines
- [x] New and existing tests pass locally
- [ ] I have added appropriate error handling
- [ ] I have added or updated documentation as needed
# Update/Fix build workflow
- `macos-latest-xlarge` is no longer available. Switch to cheaper
runner: `macos-latest-xlarge` -> `macos-latest`
- Refactor build to run matrix job under Linux and macOS
- Tune caching GH caching
- Add junit and logger properties
- Downgrade Junit to 5.14.2
- Extract `ProcessBuilder` creation logic into helper functions
- Disable `StdioClientTransportTest` on windows temporary
## How Has This Been Tested?
CI
## Breaking Changes
Functionally - no. Outdated/broken TypeScript tests were disabled
## Types of changes
<!-- What types of changes does your code introduce? Put an `x` in all
the boxes that apply: -->
- [x] Bug fix (non-breaking change which fixes an issue)
- [x] CI Update
## Checklist
<!-- Go over all the following points, and put an `x` in all the boxes
that apply. -->
- [ ] I have read the [MCP
Documentation](https://modelcontextprotocol.io)
- [ ] My code follows the repository's style guidelines
- [ ] New and existing tests pass locally
- [ ] I have added appropriate error handling
- [ ] I have added or updated documentation as needed
## Additional context
GitHub actions workflows were blocked because the selected
"macos-latest-xlarge" runner, which is not available for the free
open-source plan. With "macos-latest" workflow works.
<!-- Provide a brief summary of your changes -->
## Motivation and Context
<!-- Why is this change needed? What problem does it solve? -->
## How Has This Been Tested?
<!-- Have you tested this in a real application? Which scenarios were
tested? -->
## Breaking Changes
<!-- Will users need to update their code or configurations? -->
## Types of changes
<!-- What types of changes does your code introduce? Put an `x` in all
the boxes that apply: -->
- [x] Bug fix (non-breaking change which fixes an issue)
- [ ] New feature (non-breaking change which adds functionality)
- [ ] Breaking change (fix or feature that would cause existing
functionality to change)
- [ ] Documentation update
## Checklist
<!-- Go over all the following points, and put an `x` in all the boxes
that apply. -->
- [ ] I have read the [MCP
Documentation](https://modelcontextprotocol.io)
- [ ] My code follows the repository's style guidelines
- [ ] New and existing tests pass locally
- [ ] I have added appropriate error handling
- [ ] I have added or updated documentation as needed
## Additional context
<!-- Add any other context, implementation notes, or design decisions
-->
<!-- Provide a brief summary of your changes -->
## Motivation and Context
<!-- Why is this change needed? What problem does it solve? -->
## How Has This Been Tested?
<!-- Have you tested this in a real application? Which scenarios were
tested? -->
## Breaking Changes
<!-- Will users need to update their code or configurations? -->
## Types of changes
<!-- What types of changes does your code introduce? Put an `x` in all
the boxes that apply: -->
- [x] Bug fix (non-breaking change which fixes an issue)
- [ ] New feature (non-breaking change which adds functionality)
- [ ] Breaking change (fix or feature that would cause existing
functionality to change)
- [ ] Documentation update
## Checklist
<!-- Go over all the following points, and put an `x` in all the boxes
that apply. -->
- [ ] I have read the [MCP
Documentation](https://modelcontextprotocol.io)
- [ ] My code follows the repository's style guidelines
- [ ] New and existing tests pass locally
- [ ] I have added appropriate error handling
- [ ] I have added or updated documentation as needed
## Additional context
<!-- Add any other context, implementation notes, or design decisions
-->
# [WIP] StreamableHttpServerTransport implementation
- Implement StreamableHttpServerTransport for MCP spec
- Support both SSE streaming and direct HTTP JSON responses
- Add event store interface for resumability
> [!IMPORTANT]
> The work is in progress. StreamableHttpServerTransport is not
production-ready yet!!!
Based on #235
## How Has This Been Tested?
<!-- Have you tested this in a real application? Which scenarios were
tested? -->
## Breaking Changes
None
## Types of changes
- [ ] Bug fix (non-breaking change which fixes an issue)
- [x] New feature (non-breaking change which adds functionality)
- [ ] Breaking change (fix or feature that would cause existing
functionality to change)
- [ ] Documentation update
## Checklist
- [x] I have read the [MCP
Documentation](https://modelcontextprotocol.io)
- [x] My code follows the repository's style guidelines
- [x] New and existing tests pass locally
- [x] I have added appropriate error handling
- [x] I have added or updated documentation as needed
<!-- Provide a brief summary of your changes -->
## Motivation and Context
<!-- Why is this change needed? What problem does it solve? -->
Implemented thread-safe notification service following eventual
consistency principle.
Fixes https://github.com/modelcontextprotocol/kotlin-sdk/issues/249
Contracts:
* If the client connection and feature update happened in the same
thread, the timestamps of the events will be consequent
```
server.connect(client)
server.add(feature)
// client will receive the notification
```
```
server.add(feature)
server.connect(client)
// client will NOT receive the notification
```
* If the client connection and feature update happened in the different
threads, both options can be possible
The flow of the notification is explained in the diagram:
<img width="663" height="413" alt="image"
src="https://github.com/user-attachments/assets/e2c4c108-53dd-408d-97ef-97110ce5c979"
/>
Documentation references:
https://modelcontextprotocol.io/specification/2025-06-18/server/prompts#list-changed-notificationhttps://modelcontextprotocol.io/specification/2025-06-18/server/tools#list-changed-notificationhttps://modelcontextprotocol.io/specification/2025-06-18/server/resources#list-changed-notificationhttps://modelcontextprotocol.io/specification/2025-06-18/server/resources#subscriptions
Questions:
* I haven't found the subscription confirmed response message content
docs, how it should look like?
## How Has This Been Tested?
<!-- Have you tested this in a real application? Which scenarios were
tested? -->
Multiple tests with various notification scenarios were added
## Breaking Changes
<!-- Will users need to update their code or configurations? -->
## Types of changes
<!-- What types of changes does your code introduce? Put an `x` in all
the boxes that apply: -->
- [ ] Bug fix (non-breaking change which fixes an issue)
- [x] New feature (non-breaking change which adds functionality)
- [ ] Breaking change (fix or feature that would cause existing
functionality to change)
- [ ] Documentation update
## Checklist
<!-- Go over all the following points, and put an `x` in all the boxes
that apply. -->
- [x] I have read the [MCP
Documentation](https://modelcontextprotocol.io)
- [x] My code follows the repository's style guidelines
- [x] New and existing tests pass locally
- [x] I have added appropriate error handling
- [x] I have added or updated documentation as needed
## Additional context
<!-- Add any other context, implementation notes, or design decisions
-->
Add support for `TransportSendOptions` in `Transport.send` method
## Motivation and Context
This change extends the `Transport.send` method signature to support
advanced transport features like resumption tokens and progress
callbacks. This is needed to enable:
- Long-running request resumption after reconnection
- Request-response association tracking
- Progress token handling in transport layer
needed for #235
## How Has This Been Tested?
All transport tests passed
## Breaking Changes
Yes, it’s necessary to update the custom Transport implementations.
For users who rely on the transports provided by the sdk, there’s no
breaking change
## Types of changes
- [x] Bug fix (non-breaking change which fixes an issue)
- [x] New feature (non-breaking change which adds functionality)
- [ ] Breaking change (fix or feature that would cause existing
functionality to change)
- [ ] Documentation update
## Checklist
- [x] I have read the [MCP
Documentation](https://modelcontextprotocol.io)
- [x] My code follows the repository's style guidelines
- [x] New and existing tests pass locally
- [x] I have added appropriate error handling
- [x] I have added or updated documentation as needed
Add tests with new schema types
## Motivation and Context
<!-- Why is this change needed? What problem does it solve? -->
## How Has This Been Tested?
The repository currently contains duplicated tests:
- tests using the new schema
- tests using the old schema for compatibility checks. they will be
removed once the deprecation level is raised
## Breaking Changes
No
## Types of changes
- [ ] Bug fix (non-breaking change which fixes an issue)
- [ ] New feature (non-breaking change which adds functionality)
- [ ] Breaking change (fix or feature that would cause existing
functionality to change)
- [ ] Documentation update
- [x] Testing
## Checklist
- [x] I have read the [MCP
Documentation](https://modelcontextprotocol.io)
- [x] My code follows the repository's style guidelines
- [x] New and existing tests pass locally
- [x] I have added appropriate error handling
- [x] I have added or updated documentation as needed
---------
Co-authored-by: Konstantin Pavlov <1517853+kpavlov@users.noreply.github.com>
<!-- Provide a brief summary of your changes -->
## Motivation and Context
<!-- Why is this change needed? What problem does it solve? -->
Add ids for server sessions (auto generated when created)
Support methods proxying from server to server session by id
## How Has This Been Tested?
<!-- Have you tested this in a real application? Which scenarios were
tested? -->
## Breaking Changes
<!-- Will users need to update their code or configurations? -->
## Types of changes
<!-- What types of changes does your code introduce? Put an `x` in all
the boxes that apply: -->
- [ ] Bug fix (non-breaking change which fixes an issue)
- [x] New feature (non-breaking change which adds functionality)
- [ ] Breaking change (fix or feature that would cause existing
functionality to change)
- [ ] Documentation update
## Checklist
<!-- Go over all the following points, and put an `x` in all the boxes
that apply. -->
- [ ] I have read the [MCP
Documentation](https://modelcontextprotocol.io)
- [ ] My code follows the repository's style guidelines
- [ ] New and existing tests pass locally
- [ ] I have added appropriate error handling
- [ ] I have added or updated documentation as needed
## Additional context
<!-- Add any other context, implementation notes, or design decisions
-->
Implement the last version of the mcp schema and complete restructuring
of the mcp schema implementation from a monolithic `types.kt` file into
separate files.
- #158
- #185
- #353
- #298
- #248
## Motivation and Context
The previous implementation of the mcp schema was outdated and contained
several issues. In addition, it stored all mcp types in a single large
file, which made maintenance and further development more difficult
## How Has This Been Tested?
All tests passed
## Breaking Changes
Yes. The new types are now located in a separate package. Additionally,
many types have new parameters and modified constructors
## Types of changes
- [x] Bug fix (non-breaking change which fixes an issue)
- [x] New feature (non-breaking change which adds functionality)
- [x] Breaking change (fix or feature that would cause existing
functionality to change)
- [ ] Documentation update
## Checklist
- [x] I have read the [MCP
Documentation](https://modelcontextprotocol.io)
- [x] My code follows the repository's style guidelines
- [x] New and existing tests pass locally
- [x] I have added appropriate error handling
- [x] I have added or updated documentation as needed
## Additional context
to adopt the new structure:
**Before:**
```kotlin
import io.modelcontextprotocol.kotlin.sdk.InitializeRequest
import io.modelcontextprotocol.kotlin.sdk.Resource
```
**After:**
```kotlin
import io.modelcontextprotocol.kotlin.sdk.types.InitializeRequest
import io.modelcontextprotocol.kotlin.sdk.types.Resource
```
Replace `Instant` with `String` for `lastModified` in `Annotations`
## Motivation and Context
To fix serialization/kotlin library version conflicts
## How Has This Been Tested?
Unit test
## Breaking Changes
Yes
## Types of changes
<!-- What types of changes does your code introduce? Put an `x` in all
the boxes that apply: -->
- [x] Bug fix (non-breaking change which fixes an issue)
- [ ] New feature (non-breaking change which adds functionality)
- [x] Breaking change (fix or feature that would cause existing
functionality to change)
- [ ] Documentation update
## Checklist
<!-- Go over all the following points, and put an `x` in all the boxes
that apply. -->
- [x] I have read the [MCP
Documentation](https://modelcontextprotocol.io)
- [x] My code follows the repository's style guidelines
- [ ] New and existing tests pass locally
- [ ] I have added appropriate error handling
- [ ] I have added or updated documentation as needed
## Additional context
<!-- Add any other context, implementation notes, or design decisions
-->
<!-- Provide a brief summary of your changes -->
## Motivation and Context
The recently released openAI [Apps SDK
](https://developers.openai.com/apps-sdk/reference/#_meta-fields-the-client-provides)adds
a '__meta_' field on the Tool Descriptor. This would be in addition to
it being available on Messages. It remains optional and defaults to an
empty json object, following existing conventions.
## How Has This Been Tested?
Unit tests for serialization added
## Breaking Changes
N/A
## Types of changes
<!-- What types of changes does your code introduce? Put an `x` in all
the boxes that apply: -->
- [ ] Bug fix (non-breaking change which fixes an issue)
- [X] New feature (non-breaking change which adds functionality)
- [ ] Breaking change (fix or feature that would cause existing
functionality to change)
- [ ] Documentation update
## Checklist
<!-- Go over all the following points, and put an `x` in all the boxes
that apply. -->
- [X] I have read the [MCP
Documentation](https://modelcontextprotocol.io)
- [X] My code follows the repository's style guidelines
- [X] New and existing tests pass locally
- [X] I have added appropriate error handling
- [X] I have added or updated documentation as needed
## Additional context
https://developers.openai.com/apps-sdkhttps://developers.openai.com/apps-sdk/reference/#_meta-fields-the-client-provides
---------
Co-authored-by: Pavel Gorgulov <devcrocod@gmail.com>
## Motivation and Context
- 📦 Unifies Ktor library versioning by introducing the Ktor BOM
dependency.
- ✅ Re-enable build of MCP Server Sample
## How Has This Been Tested?
Regression tests
## Breaking Changes
No
## Types of changes
<!-- What types of changes does your code introduce? Put an `x` in all
the boxes that apply: -->
- [ ] Bug fix (non-breaking change which fixes an issue)
- [ ] New feature (non-breaking change which adds functionality)
- [ ] Breaking change (fix or feature that would cause existing
functionality to change)
- [ ] Documentation update
- [x] Build configuration update
## Checklist
<!-- Go over all the following points, and put an `x` in all the boxes
that apply. -->
- [x] I have read the [MCP
Documentation](https://modelcontextprotocol.io)
- [x] My code follows the repository's style guidelines
- [x] New and existing tests pass locally
- [x] I have added appropriate error handling
- [x] I have added or updated documentation as needed
## Additional context
<!-- Add any other context, implementation notes, or design decisions
-->
Fix#293
Also fixed a bug with initialization: properties must be declared before
the init block; otherwise, the initialization order is violated and an
NPE will occur in the init block.
## Motivation and Context
After initialization, MCP clients send a `logging/setLevel` request if
the logging capability is enabled. This request was previously not
handled, leading to an error that blocked the use of the MCP server in
the inspector and other clients.
## How Has This Been Tested?
Added integration test
## Breaking Changes
None
## Types of changes
- [x] Bug fix (non-breaking change which fixes an issue)
- [ ] New feature (non-breaking change which adds functionality)
- [ ] Breaking change (fix or feature that would cause existing
functionality to change)
- [ ] Documentation update
## Checklist
- [x] I have read the [MCP
Documentation](https://modelcontextprotocol.io)
- [x] My code follows the repository's style guidelines
- [x] New and existing tests pass locally
- [x] I have added appropriate error handling
- [x] I have added or updated documentation as needed
