## 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
## 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
-->
# 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.
- 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
# 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.
# [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
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>
* Modularize SDK: migrated client and server implementations to separate modules. Removed old configuration files and reorganized the source code structure
* add support native targets and update js/wasm configurations
* Refactor sample projects: add samples as composite builds, replace hardcoded dependencies with version catalog, remove obsolete gradle wrapper files
* Update .gitignore: exclude SWE agent directories (.claude/ and .junie/)
* Refine CodeQL workflow: update Kotlin build steps to target individual modules separately instead of building all at once