Aspire MCP server

The Aspire MCP server gives AI coding agents direct runtime access to your running Aspire application. Through the Model Context Protocol (MCP), agents can query resource status, read logs, inspect distributed traces, and execute commands — without you copy-pasting terminal output.

The MCP server is configured automatically when you run aspire agent init and select Install Aspire MCP server.

Configuration

The aspire agent init command creates MCP server configuration files for your detected AI environment:

VS Code

Claude Code

Copilot CLI

OpenCode

Tools

The Aspire MCP server provides the following tools to AI agents:

Tool	Description
`list_resources`	Lists all resources, including state, health status, source, endpoints, and commands
`list_console_logs`	Lists console logs for a resource
`list_structured_logs`	Lists structured logs, optionally filtered by resource name
`list_traces`	Lists distributed traces, optionally filtered by resource name
`list_trace_structured_logs`	Lists structured logs for a specific trace
`execute_resource_command`	Executes a resource command (start, stop, restart)
`list_apphosts`	Lists detected AppHost connections and their scope
`select_apphost`	Selects which AppHost to use when multiple are running
`list_integrations`	Lists available Aspire hosting integration packages
`get_integration_docs`	Gets documentation for a specific integration package
`list_docs`	Lists all available documentation pages from aspire.dev
`search_docs`	Searches aspire.dev documentation using keyword-based search
`get_doc`	Retrieves the full content of a documentation page by slug
`doctor`	Diagnoses Aspire environment issues and verifies setup
`refresh_tools`	Requests the server to re-emit its tool list for clients to re-fetch

Exclude resources from MCP

By default, all resources, console logs, and telemetry are accessible through the MCP server. You can exclude specific resources and their associated telemetry by annotating them with ExcludeFromMcp():

var builder = DistributedApplication.CreateBuilder(args);
  
var apiservice = builder.AddProject<Projects.AspireApp_ApiService>("apiservice")
    .ExcludeFromMcp();
  
builder.AddProject<Projects.AspireApp_Web>("webfrontend")
    .WithExternalHttpEndpoints()
    .WithReference(apiservice);
  
builder.Build().Run();

TypeScript

const builder = await createBuilder();
  
const apiservice = await builder
    .addProject("apiservice", "./api/ApiService.csproj")
    .excludeFromMcp();
  
await builder
    .addProject("webfrontend", "./web/Web.csproj")
    .withExternalHttpEndpoints()
    .withReference(apiservice);
  
await builder.build().run();

Security

The Aspire MCP server is a development-time tool designed for local use.

How it works

The MCP server uses the STDIO transport protocol when started via aspire agent mcp:

The MCP server runs as a local child process spawned by your AI assistant.
Communication happens over standard input/output (STDIO) pipes.
There are no open network ports — the server doesn't listen on any network interface.
Only the parent process (your AI assistant) can communicate with the MCP server.

Tip

Because STDIO transport uses pipes rather than network sockets, there is no network attack surface. The MCP server is only accessible to the AI assistant process that started it.

What data is accessible

The MCP server provides access to:

Resource metadata — names, types, states, health status, endpoints, and commands
Console logs — standard output and error streams
Structured logs — log entries via OpenTelemetry
Distributed traces — request flow across resources
Integration catalog — available hosting integration packages
Product documentation — Official LLMS.txt-based aspire.dev content

The MCP server does not expose:

Source code or file system contents
Environment variable values or secrets
Network traffic or raw request/response payloads
Access to the host machine beyond the Aspire AppHost process

Authentication

With STDIO transport (the default), no additional authentication is required — communication is restricted to the local process pipe.

For the HTTP-based MCP endpoint exposed by the Aspire dashboard (used in manual MCP configuration for older Aspire versions), an API key (x-mcp-api-key header) is required.

Enterprise considerations

For teams evaluating the Aspire MCP server:

Development-time only — not included in published or deployed applications
No external network access — no network listeners when using STDIO transport
Data stays local — telemetry remains on the developer's machine. Data shared with AI assistants is governed by the assistant's own data policies
Granular access control — use ExcludeFromMcp() to restrict sensitive resources
No persistent storage — all data is in memory for the session duration
Open specification — implements the Model Context Protocol specification

Deployment considerations

The MCP server is part of the Aspire CLI tooling and runs separately from your AppHost — it doesn't require explicit exclusion from deployments.

If your AppHost includes dev-only resources, use ExecutionContext.IsRunMode to exclude them from production:

var builder = DistributedApplication.CreateBuilder(args);
  
var api = builder.AddProject<Projects.Api>("api");
  
if (builder.ExecutionContext.IsRunMode)
{
    // Only available during local development
    builder.AddContainer("dev-tool", "some-dev-image");
}
  
builder.Build().Run();

TypeScript

const builder = await createBuilder();
  
const api = await builder
    .addProject("api", "./api/Api.csproj");
  
if (await builder.executionContext.isRunMode()) {
    // Only available during local development
    await builder.addContainer("dev-tool", "some-dev-image");
}
  
await builder.build().run();

Limitations

AI models have limits on how much data they can process. The Aspire MCP server may limit data returned from tools:

Large data fields (e.g., long stack traces) may be truncated
Large collections of telemetry may be shortened by omitting older items

Troubleshooting

If you run into issues, check the open MCP issues on GitHub.

AppHost detection

The MCP server automatically detects running AppHosts within the working directory scope:

It continuously monitors for AppHost changes — no restart needed
Use list_apphosts to see detected AppHosts
Use select_apphost to switch between multiple running AppHosts

Note

If your AI assistant doesn't detect your AppHost, verify it's running with aspire start and that the assistant was started from the same workspace directory.

If your agent can't connect

1
Verify the Aspire CLI is installed:
```
aspire --version
```
2
Confirm your AppHost is running:
```
aspire start
```
3
Test the MCP server directly:
```
aspire agent mcp
```
If it starts without errors, the issue is in your AI assistant's configuration.
4
Regenerate configuration:
```
aspire agent init
```

Claude Code issues

Ensure .mcp.json exists in your project root — run aspire agent init to regenerate
On Windows, commands like npx require a cmd.exe /c prefix
Restart Claude Code to re-establish stale MCP connections