modelcontextprotocol/typescript-sdk
Watch
1
0
Fork
You've already forked typescript-sdk
 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions 1

feat: allow overriding protocol versions in Client, Server, and Transport (#1448)

Browse source 
Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>
This commit is contained in:
Matt 2026-02-03 14:59:12 +00:00 • committed by GitHub
commit 160902eb2e
No known key found for this signature in database
GPG key ID: B5690EEEBB952194
2 changed files with 119 additions and 9 deletions
Download patch file Download diff file Expand all files Collapse all files

7
packages/server/src/server/server.ts
View file

@ -51,8 +51,7 @@ import {
McpError,
mergeCapabilities,
Protocol,
safeParse,
SUPPORTED_PROTOCOL_VERSIONS
safeParse
} from '@modelcontextprotocol/core';
import { ExperimentalServerTasks } from '../experimental/tasks/server.js';
@ -435,7 +434,9 @@ export class Server<
this._clientCapabilities = request.params.capabilities;
this._clientVersion = request.params.clientInfo;
const protocolVersion = SUPPORTED_PROTOCOL_VERSIONS.includes(requestedVersion) ? requestedVersion : LATEST_PROTOCOL_VERSION;
const protocolVersion = this._supportedProtocolVersions.includes(requestedVersion)
? requestedVersion
: (this._supportedProtocolVersions[0] ?? LATEST_PROTOCOL_VERSION);
return {
protocolVersion,

26
packages/server/src/server/streamableHttp.ts
View file

@ -142,6 +142,18 @@ export interface WebStandardStreamableHTTPServerTransportOptions {
* client reconnection timing for polling behavior.
*/
retryInterval?: number;
/**
* List of protocol versions that this transport will accept.
* Used to validate the mcp-protocol-version header in incoming requests.
*
* Note: When using Server.connect(), the server automatically passes its
* supportedProtocolVersions to the transport, so you typically don't need
* to set this option directly.
*
* @default SUPPORTED_PROTOCOL_VERSIONS
*/
supportedProtocolVersions?: string[];
}
/**
@ -220,6 +232,7 @@ export class WebStandardStreamableHTTPServerTransport implements Transport {
private _allowedOrigins?: string[];
private _enableDnsRebindingProtection: boolean;
private _retryInterval?: number;
private _supportedProtocolVersions: string[];
sessionId?: string;
onclose?: () => void;
@ -236,6 +249,7 @@ export class WebStandardStreamableHTTPServerTransport implements Transport {
this._allowedOrigins = options.allowedOrigins;
this._enableDnsRebindingProtection = options.enableDnsRebindingProtection ?? false;
this._retryInterval = options.retryInterval;
this._supportedProtocolVersions = options.supportedProtocolVersions ?? SUPPORTED_PROTOCOL_VERSIONS;
}
/**
@ -249,6 +263,14 @@ export class WebStandardStreamableHTTPServerTransport implements Transport {
this._started = true;
}
/**
* Sets the supported protocol versions for header validation.
* Called by the server during connect() to pass its supported versions.
*/
setSupportedProtocolVersions(versions: string[]): void {
this._supportedProtocolVersions = versions;
}
/**
* Helper to create a JSON error response
*/
@ -848,11 +870,11 @@ export class WebStandardStreamableHTTPServerTransport implements Transport {
private validateProtocolVersion(req: Request): Response | undefined {
const protocolVersion = req.headers.get('mcp-protocol-version');
if (protocolVersion !== null && !SUPPORTED_PROTOCOL_VERSIONS.includes(protocolVersion)) {
if (protocolVersion !== null && !this._supportedProtocolVersions.includes(protocolVersion)) {
return this.createJsonErrorResponse(
400,
-32_000,
`Bad Request: Unsupported protocol version: ${protocolVersion} (supported versions: ${SUPPORTED_PROTOCOL_VERSIONS.join(', ')})`
`Bad Request: Unsupported protocol version: ${protocolVersion} (supported versions: ${this._supportedProtocolVersions.join(', ')})`
);
}
return undefined;