MCP prompts not surfaced in Claude VS Code extension (tools work fine)

Summary

MCP prompts (exposed via @mcp.prompt() / the prompts/list capability) are not surfaced or callable in the Claude VS Code extension, while tools from the same server work correctly. The same server and prompt work as expected in GitHub Copilot and the Claude CLI (claude).

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Environment

| Item | Value |
|------|-------|
| OS | Windows 11 Home (10.0.26200) |
| VS Code | 1.123.0 |
| Claude VS Code Extension | 2.1.168 |
| Python | 3.13.7 |
| mcp (FastMCP) | 1.27.2 |
| MCP server transport | stdio |

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Steps to Reproduce

1. Create a minimal Python MCP server using FastMCP that exposes both a tool and a prompt:

```python
# server.py
import requests
from mcp.server.fastmcp import FastMCP

mcp = FastMCP("chuck-norris")

@mcp.tool()
def get_random_joke() -> str:
"""Return a random Chuck Norris joke."""
response = requests.get("https://api.chucknorris.io/jokes/random", timeout=10)
response.raise_for_status()
return response.json()["value"]

@mcp.prompt()
def chuckme() -> str:
"""Fetch a random Chuck Norris joke and present it."""
joke = get_random_joke()
return f"Here's a Chuck Norris joke for you:\n\n{joke}"

if __name__ == "__main__":
mcp.run()
```

1. Register the server for Claude in .mcp.json at the project root:

``json
{
"mcpServers": {
"chuck-norris": {
"command": "C:\path\to\.venv\Scripts\python.exe",
"args": ["path/to/server.py"]
}
}
}
``

For reference, the equivalent Copilot registration (.vscode/mcp.json) where the prompt does work:

``json
{
"servers": {
"chuck-server": {
"type": "stdio",
"command": "C:\path\to\.venv\Scripts\python.exe",
"args": ["path/to/server.py"],
"cwd": "${workspaceFolder}"
}
}
}
``

1. Open VS Code and confirm the MCP server starts (tools appear in the Claude extension's tool picker).

1. Attempt to invoke the chuckme prompt — e.g. by typing /chuckme or using the prompt picker UI (if any).

---

Expected Behavior

The prompt chuckme should be discoverable and callable from within the Claude VS Code extension, consistent with how it behaves in:

• GitHub Copilot — prompt appears and executes correctly.
• Claude CLI — prompt is listed and callable (e.g. as /mcp__chuck-norris__chuckme).

---

Actual Behavior

The prompt is not surfaced in the Claude VS Code extension. The tools from the same server (get_random_joke, etc.) are available and work correctly, indicating the server connects successfully and the tools/list capability is handled — but prompts/list appears to be ignored or unsupported.

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Additional Context

• This is a prompts vs. tools distinction: MCP defines three capability types — tools, resources, and prompts. The extension appears to implement tools but not prompts.
• The server correctly advertises the prompts capability over stdio; other clients consume it without issue.
• No errors are visible in the extension output panel related to the prompt registration.