-32700
Parse Error
JSON-RPC 2.0
JSON-RPC parse error (-32700) means the server received a message it could not parse as valid JSON. The bytes were not valid JSON syntax. This is always a client-side serialization bug.
Code
-32700
Decimal
-32700
Standard
JSON-RPC 2.0
Description
Parse Error is the lowest-level JSON-RPC error. The server received data over the transport but could not deserialize it as JSON. Common causes include sending binary data over stdio, writing a partial message before the newline terminator, or a bug in the JSON serialization library. Note that -32700 is a JSON-RPC 2.0 standard error code, not MCP-specific. The error response has no id field (null) because the server could not parse the request to extract an id.
Common Causes
- –Message is not valid JSON (syntax error)
- –Binary data sent over stdio transport instead of text
- –Newline sent in the middle of a JSON message (partial write)
- –BOM (byte order mark) prepended to JSON bytes
- –JSON serialization library bug producing invalid output