Module: Coatepec::MCP::Response

Defined in:
lib/coatepec/mcp/response.rb

Overview

Builds the pretty-printed JSON {ok: true, data:, meta:} / {ok: false, error:} envelope that every Coatepec tool response wraps in a single text content block.

Constant Summary collapse

MAX_RESPONSE_BYTES =

Per-stream caps in Spec::Result bound stdout/stderr, but the fully assembled envelope (500 examples with long descriptions) can still exceed what an MCP client will accept, so cap it here -- the single place every tool response is built.

1024 * 1024

Class Method Summary collapse

Class Method Details

.error(err) ⇒ Object 



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# File 'lib/coatepec/mcp/response.rb', line 27

def error(err)
  payload = {
    ok: false,
    error: { code: err.code.to_s, message: err.message, details: err.details }
  }
  ::MCP::Tool::Response.new([{ type: "text", text: JSON.pretty_generate(payload) }], error: true)
end

.ok(data:, meta: {}) ⇒ Object 



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# File 'lib/coatepec/mcp/response.rb', line 20

def ok(data:, meta: {})
  text = JSON.pretty_generate(ok: true, data: data, meta: meta)
  return oversized_response if text.bytesize > MAX_RESPONSE_BYTES

  ::MCP::Tool::Response.new([{ type: "text", text: text }])
end

.oversized_response ⇒ Object 



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# File 'lib/coatepec/mcp/response.rb', line 35

def oversized_response
  error(Coatepec::Error.new(:response_too_large, "Result exceeds the 1 MiB response limit"))
end