Class McpHeaderEncoder

Namespace

ModelContextProtocol.Protocol

Assembly

ModelContextProtocol.Core.dll

Encodes and decodes parameter values for use in MCP HTTP headers according to the HTTP Standardization SEP.

public static class McpHeaderEncoder

Inheritance

object

McpHeaderEncoder

Inherited Members

object.Equals(object)

object.Equals(object, object)

object.GetHashCode()

object.GetType()

object.MemberwiseClone()

object.ReferenceEquals(object, object)

object.ToString()

Remarks

This encoder handles conversion of parameter values to HTTP header-safe strings, including Base64 encoding for values that cannot be safely transmitted as plain text.

Per SEP-2243 only primitive parameter types are supported: string, integer, and boolean. The JSON Schema number type is not permitted, and integer values must be within the JavaScript safe integer range (−2^53+1 to 2^53−1).

Encoding rules:

• Plain ASCII values (0x20-0x7E): sent as-is
• Values with leading/trailing whitespace: Base64 encoded with =?base64?{value}?= wrapper
• Non-ASCII characters: Base64 encoded
• Control characters: Base64 encoded
• Plain ASCII values that themselves match the =?base64?...?= sentinel pattern: Base64 encoded to avoid ambiguity

Methods

ConvertToHeaderValue(JsonElement)

Converts a JsonElement value to an encoded header value string.

public static string? ConvertToHeaderValue(JsonElement element)

Parameters

element JsonElement

The JSON element to convert.

Returns

string

The encoded header value, or null if the element is not a supported primitive type.

ConvertToHeaderValue(JsonNode)

Converts a JsonNode value to an encoded header value string.

public static string? ConvertToHeaderValue(JsonNode node)

Parameters

node JsonNode

The JSON node to convert.

Returns

string

The encoded header value, or null if the node is not a JsonValue or is not a supported primitive type.

DecodeValue(string?)

Decodes a header value that may be Base64-encoded according to SEP rules.

public static string? DecodeValue(string? headerValue)

Parameters

headerValue string

The header value to decode.

Returns

string

The decoded string value, or null if decoding fails. If the value is not Base64-encoded, returns the original value.

EncodeValue(bool)

Encodes a boolean parameter value for use in an HTTP header.

public static string EncodeValue(bool value)

Parameters

value bool

The boolean value to encode.

Returns

string

The encoded header value ("true" or "false").

EncodeValue(long)

Encodes an integer parameter value for use in an HTTP header.

public static string EncodeValue(long value)

Parameters

value long

The integer value to encode.

Returns

string

The decimal string representation of the value.

EncodeValue(object?)

Encodes a parameter value for use in an HTTP header.

public static string? EncodeValue(object? value)

Parameters

value object

The value to encode. Supported types are string, integer, and boolean.

Returns

string

The encoded header value, or null if the value is null or is not a supported type (string, integer, or boolean).

EncodeValue(string?)

Encodes a string parameter value for use in an HTTP header.

public static string? EncodeValue(string? value)

Parameters

value string

The string value to encode.

Returns

string

The encoded header value, or null if value is null.