Variable TransportErrorMessage`Const`

TransportErrorMessage: {
    DNS_REBINDING_BLOCKED: "Forbidden: Invalid Host header";
    INTERNAL_ERROR: "An internal error occurred";
    INVALID_ACCEPT_HEADER: "Invalid Accept header";
    INVALID_CONTENT_TYPE: "Content-Type must be application/json";
    INVALID_JSON: "Invalid JSON";
    INVALID_JSONRPC: "Invalid JSON-RPC version";
    INVALID_JSONRPC_BATCH: "Invalid batch request: array must not be empty";
    INVALID_JSONRPC_VERSION: "JSON-RPC version must be 2.0";
    MISSING_ACCEPT_HEADER: "Missing Accept header";
    MISSING_JSONRPC_METHOD: "Missing method field";
    ORIGIN_NOT_ALLOWED: "Forbidden: Invalid Origin header";
    PROXY_NOT_CONFIGURED: "Bad Gateway: proxy headers detected but trust proxy is not configured";
    RATE_LIMIT_EXCEEDED: "Too many requests from this IP, please try again later.";
    SESSION_ID_OR_PARAM_REQUIRED: "Mcp-Session-Id header or sessionId query parameter required";
    SESSION_ID_QUERY_REQUIRED: "sessionId query parameter required";
    SESSION_ID_REQUIRED: "Mcp-Session-Id header required";
    SESSION_NOT_FOUND: "Session not found or expired";
    SESSION_NOT_FOUND_REINIT: "Session has expired. Please re-initialize.";
    SSE_DISABLED: "SSE transport is disabled. Enable with MCP_LEGACY_SSE_ENABLED=true or use Streamable HTTP transport.";
    TOO_MANY_SESSIONS: "Service unavailable: too many active sessions";
    TRANSPORT_CLOSED: "Transport is closed";
    UNSUPPORTED_PROTOCOL_VERSION: "Unsupported MCP-Protocol-Version";
} = ...

Transport-specific error message constants.

Provides a convenient API for transport layer code to reference standardized error messages.

Type Declaration

ReadonlyDNS_REBINDING_BLOCKED: "Forbidden: Invalid Host header"
ReadonlyINTERNAL_ERROR: "An internal error occurred"
ReadonlyINVALID_ACCEPT_HEADER: "Invalid Accept header"
ReadonlyINVALID_CONTENT_TYPE: "Content-Type must be application/json"
ReadonlyINVALID_JSON: "Invalid JSON"
ReadonlyINVALID_JSONRPC: "Invalid JSON-RPC version"
ReadonlyINVALID_JSONRPC_BATCH: "Invalid batch request: array must not be empty"
ReadonlyINVALID_JSONRPC_VERSION: "JSON-RPC version must be 2.0"
ReadonlyMISSING_ACCEPT_HEADER: "Missing Accept header"
ReadonlyMISSING_JSONRPC_METHOD: "Missing method field"
ReadonlyORIGIN_NOT_ALLOWED: "Forbidden: Invalid Origin header"
ReadonlyPROXY_NOT_CONFIGURED: "Bad Gateway: proxy headers detected but trust proxy is not configured"
ReadonlyRATE_LIMIT_EXCEEDED: "Too many requests from this IP, please try again later."
ReadonlySESSION_ID_OR_PARAM_REQUIRED: "Mcp-Session-Id header or sessionId query parameter required"
ReadonlySESSION_ID_QUERY_REQUIRED: "sessionId query parameter required"
ReadonlySESSION_ID_REQUIRED: "Mcp-Session-Id header required"
ReadonlySESSION_NOT_FOUND: "Session not found or expired"
ReadonlySESSION_NOT_FOUND_REINIT: "Session has expired. Please re-initialize."
ReadonlySSE_DISABLED: "SSE transport is disabled. Enable with MCP_LEGACY_SSE_ENABLED=true or use Streamable HTTP transport."
ReadonlyTOO_MANY_SESSIONS: "Service unavailable: too many active sessions"
ReadonlyTRANSPORT_CLOSED: "Transport is closed"
ReadonlyUNSUPPORTED_PROTOCOL_VERSION: "Unsupported MCP-Protocol-Version"

Example

import { TransportErrorMessage } from '../errors/index.js';

res.status(HttpStatus.BAD_REQUEST)
   .json({ error: TransportErrorMessage.SESSION_ID_REQUIRED });

Variable TransportErrorMessage`Const`

Type Declaration

`Readonly`DNS_REBINDING_BLOCKED: "Forbidden: Invalid Host header"

`Readonly`INTERNAL_ERROR: "An internal error occurred"

`Readonly`INVALID_ACCEPT_HEADER: "Invalid Accept header"

`Readonly`INVALID_CONTENT_TYPE: "Content-Type must be application/json"

`Readonly`INVALID_JSON: "Invalid JSON"

`Readonly`INVALID_JSONRPC: "Invalid JSON-RPC version"

`Readonly`INVALID_JSONRPC_BATCH: "Invalid batch request: array must not be empty"

`Readonly`INVALID_JSONRPC_VERSION: "JSON-RPC version must be 2.0"

`Readonly`MISSING_ACCEPT_HEADER: "Missing Accept header"

`Readonly`MISSING_JSONRPC_METHOD: "Missing method field"

`Readonly`ORIGIN_NOT_ALLOWED: "Forbidden: Invalid Origin header"

`Readonly`PROXY_NOT_CONFIGURED: "Bad Gateway: proxy headers detected but trust proxy is not configured"

`Readonly`RATE_LIMIT_EXCEEDED: "Too many requests from this IP, please try again later."

`Readonly`SESSION_ID_OR_PARAM_REQUIRED: "Mcp-Session-Id header or sessionId query parameter required"

`Readonly`SESSION_ID_QUERY_REQUIRED: "sessionId query parameter required"

`Readonly`SESSION_ID_REQUIRED: "Mcp-Session-Id header required"

`Readonly`SESSION_NOT_FOUND: "Session not found or expired"

`Readonly`SESSION_NOT_FOUND_REINIT: "Session has expired. Please re-initialize."

`Readonly`SSE_DISABLED: "SSE transport is disabled. Enable with MCP_LEGACY_SSE_ENABLED=true or use Streamable HTTP transport."

`Readonly`TOO_MANY_SESSIONS: "Service unavailable: too many active sessions"

`Readonly`TRANSPORT_CLOSED: "Transport is closed"

`Readonly`UNSUPPORTED_PROTOCOL_VERSION: "Unsupported MCP-Protocol-Version"

Example

Settings

Variable TransportErrorMessageConst

Type Declaration

ReadonlyDNS_REBINDING_BLOCKED: "Forbidden: Invalid Host header"

ReadonlyINTERNAL_ERROR: "An internal error occurred"

ReadonlyINVALID_ACCEPT_HEADER: "Invalid Accept header"

ReadonlyINVALID_CONTENT_TYPE: "Content-Type must be application/json"

ReadonlyINVALID_JSON: "Invalid JSON"

ReadonlyINVALID_JSONRPC: "Invalid JSON-RPC version"

ReadonlyINVALID_JSONRPC_BATCH: "Invalid batch request: array must not be empty"

ReadonlyINVALID_JSONRPC_VERSION: "JSON-RPC version must be 2.0"

ReadonlyMISSING_ACCEPT_HEADER: "Missing Accept header"

ReadonlyMISSING_JSONRPC_METHOD: "Missing method field"

ReadonlyORIGIN_NOT_ALLOWED: "Forbidden: Invalid Origin header"

ReadonlyPROXY_NOT_CONFIGURED: "Bad Gateway: proxy headers detected but trust proxy is not configured"

ReadonlyRATE_LIMIT_EXCEEDED: "Too many requests from this IP, please try again later."

ReadonlySESSION_ID_OR_PARAM_REQUIRED: "Mcp-Session-Id header or sessionId query parameter required"

ReadonlySESSION_ID_QUERY_REQUIRED: "sessionId query parameter required"

ReadonlySESSION_ID_REQUIRED: "Mcp-Session-Id header required"

ReadonlySESSION_NOT_FOUND: "Session not found or expired"

ReadonlySESSION_NOT_FOUND_REINIT: "Session has expired. Please re-initialize."

ReadonlySSE_DISABLED: "SSE transport is disabled. Enable with MCP_LEGACY_SSE_ENABLED=true or use Streamable HTTP transport."

ReadonlyTOO_MANY_SESSIONS: "Service unavailable: too many active sessions"

ReadonlyTRANSPORT_CLOSED: "Transport is closed"

ReadonlyUNSUPPORTED_PROTOCOL_VERSION: "Unsupported MCP-Protocol-Version"

Example

Settings

Variable TransportErrorMessage`Const`

`Readonly`DNS_REBINDING_BLOCKED: "Forbidden: Invalid Host header"

`Readonly`INTERNAL_ERROR: "An internal error occurred"

`Readonly`INVALID_ACCEPT_HEADER: "Invalid Accept header"

`Readonly`INVALID_CONTENT_TYPE: "Content-Type must be application/json"

`Readonly`INVALID_JSON: "Invalid JSON"

`Readonly`INVALID_JSONRPC: "Invalid JSON-RPC version"

`Readonly`INVALID_JSONRPC_BATCH: "Invalid batch request: array must not be empty"

`Readonly`INVALID_JSONRPC_VERSION: "JSON-RPC version must be 2.0"

`Readonly`MISSING_ACCEPT_HEADER: "Missing Accept header"

`Readonly`MISSING_JSONRPC_METHOD: "Missing method field"

`Readonly`ORIGIN_NOT_ALLOWED: "Forbidden: Invalid Origin header"

`Readonly`PROXY_NOT_CONFIGURED: "Bad Gateway: proxy headers detected but trust proxy is not configured"

`Readonly`RATE_LIMIT_EXCEEDED: "Too many requests from this IP, please try again later."

`Readonly`SESSION_ID_OR_PARAM_REQUIRED: "Mcp-Session-Id header or sessionId query parameter required"

`Readonly`SESSION_ID_QUERY_REQUIRED: "sessionId query parameter required"

`Readonly`SESSION_ID_REQUIRED: "Mcp-Session-Id header required"

`Readonly`SESSION_NOT_FOUND: "Session not found or expired"

`Readonly`SESSION_NOT_FOUND_REINIT: "Session has expired. Please re-initialize."

`Readonly`SSE_DISABLED: "SSE transport is disabled. Enable with MCP_LEGACY_SSE_ENABLED=true or use Streamable HTTP transport."

`Readonly`TOO_MANY_SESSIONS: "Service unavailable: too many active sessions"

`Readonly`TRANSPORT_CLOSED: "Transport is closed"

`Readonly`UNSUPPORTED_PROTOCOL_VERSION: "Unsupported MCP-Protocol-Version"