Decompiled and Source-Generated Document URIs

When the metadataUris feature is enabled, textDocument/definition on a symbol that lives outside the user's own source files returns a virtual csharp:/ URI instead of a temporary file path. There are two kinds:

Kind	URI format
Decompiled assembly symbol	csharp:/<project.csproj>/decompiled/<Symbol>.cs
Source-generated file	csharp:/<project.csproj>/generated/<HintName>

The URI can be passed to the custom csharp/metadata LSP request to retrieve the source text.

Enabling the feature

Any one of the following is sufficient:

• Set csharp.useMetadataUris = true in your editor's workspace configuration (workspace/configuration / workspace/didChangeConfiguration)
• Pass --features metadata-uris on the command line
• Set the experimental.csharp.metadataUris client capability to true during LSP initialization

csharp/metadata request

Request

{
  "textDocument": {
    "uri": "csharp:/<project.csproj>/decompiled/System.String.cs"
  }
}

The uri must be a csharp:/ URI obtained from a prior textDocument/definition (or similar) response. Both decompiled and source-generated URIs are accepted.

Response

{
  "projectName": "MyProject",
  "assemblyName": "System.Runtime",
  "symbolName": "System.String",
  "source": "using System.Buffers;\n..."
}

Field	Description
projectName	Name of the Roslyn project that owns the document
assemblyName	Assembly name (decompiled: containing assembly; generated: project assembly)
symbolName	Fully-qualified type name (decompiled) or hint name (source-generated)
source	Full source text of the decompiled or generated document

Editor integration

Neovim

local params = { textDocument = { uri = uri } }
local result, err = client.request_sync("csharp/metadata", params, 10000)
if not err then
  local source = result.result.source
end

A ready-made plugin is available: csharpls-extended-lsp.nvim

Visual Studio Code

vscode-csharp-ls