[Lldb-commits] [lldb] [lldb] Add Model Context Protocol (MCP) support to LLDB (PR #143628)

[Jonas Devlieghere via lldb-commits]

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@@ -0,0 +1,131 @@
+//===- Protocol.h ---------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLDB_PLUGINS_PROTOCOL_MCP_PROTOCOL_H
+#define LLDB_PLUGINS_PROTOCOL_MCP_PROTOCOL_H
+
+#include "llvm/Support/JSON.h"
+#include <optional>
+#include <string>
+
+namespace lldb_private::mcp::protocol {
+
+static llvm::StringLiteral kProtocolVersion = "2025-03-26";
+
+struct Request {
+  uint64_t id = 0;
+  std::string method;
+  std::optional<llvm::json::Value> params;
+};
+
+llvm::json::Value toJSON(const Request &);
+bool fromJSON(const llvm::json::Value &, Request &, llvm::json::Path);
+
+struct Error {
+  int64_t code = 0;
+  std::string message;
+  std::optional<std::string> data;
+};
+
+llvm::json::Value toJSON(const Error &);
+bool fromJSON(const llvm::json::Value &, Error &, llvm::json::Path);
+
+struct ProtocolError {
+  uint64_t id = 0;
+  Error error;
+};
+
+llvm::json::Value toJSON(const ProtocolError &);
+bool fromJSON(const llvm::json::Value &, ProtocolError &, llvm::json::Path);
+
+struct Response {
+  uint64_t id = 0;
+  std::optional<llvm::json::Value> result;
+  std::optional<Error> error;
+};
+
+llvm::json::Value toJSON(const Response &);
+bool fromJSON(const llvm::json::Value &, Response &, llvm::json::Path);
+
+struct Notification {
+  std::string method;
+  std::optional<llvm::json::Value> params;
+};
+
+llvm::json::Value toJSON(const Notification &);
+bool fromJSON(const llvm::json::Value &, Notification &, llvm::json::Path);
+
+struct ToolCapability {
+  bool listChanged = false;
+};
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JDevlieghere wrote:

Yup, I think that's something we could support. Completion was added in the latest revision of the spec and to support older tools I've settled on the previous revision for now, but this might be a good motivator to move to the next version. 

https://github.com/llvm/llvm-project/pull/143628