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VSCode: Toolset name mismatch: 'github/*' fails with Unknown tool, but 'github' warns it's deprecated #1402

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Description

@LorcanChinnock

Describe the bug

When referencing the GitHub MCP toolset inside a VS Code agent configuration, using the recommended github/* pattern does not work.

  • Referencing the toolset as github/* results in an Unknown tool error.
Image
  • Referencing the toolset simply as github works, but produces a warning stating that it has been renamed to github/*.
Image

This creates a contradictory situation where:

  • The recommended name (github/*) fails.
  • The fallback name (github) works but warns that it should be replaced with github/*.

Affected version

I am using the remote GitHub MCP integration inside VS Code, so it does not expose a version.

VS Code version:
1.106.0

OS:
macOS Sequoia Version 15.7.2 (24G325)

Steps to reproduce the behavior

  1. In a VS Code agent configuration, reference the GitHub MCP toolset like this:

    "tools": ["github/*"]
  2. VS Code reports an error:

    Unknown tool 'github/github-mcp-server/*'.
    
  3. Change the reference to:

    "tools": ["github"]
  4. The agent loads, but VS Code shows a warning:

    Tool or toolset 'github' has been renamed, use 'github/*' instead.
    

Expected vs actual behavior

Expected behavior:
Referencing the toolset as github/* should work without errors and should be the correct, supported naming format.

Actual behavior:

  • github/* → Fails with Unknown tool
  • github → Works, but warns that the toolset has been renamed to github/*, which cannot actually be used

Logs

Unknown tool error:

Unknown tool 'github/github-mcp-server/*'.

Renaming warning:

Tool or toolset 'github' has been renamed, use 'github/*' instead.

Activity

  1. GordonBeeming commented on Nov 18, 2025

    @GordonBeeming

    I'm getting the same thing for close to 2 weeks now... thought it was a iss-me but looks to be an issue 😕

    This affects all MCPs it looks like, not just the github tools

    Image
  2. Chuxel commented on Nov 18, 2025

    @Chuxel

    cc @aeschli on the VS Code team to look. How where the MCP servers installed here? @aeschli mentioned that if you install via @mcp it should have the right name, but if you manually name the MCP server something else, this could happen.

    One note is that tactically you can list both tools and the respective products will ignore anything not supported. I also do not think these aliases will work in the old .github/chatmodes location, only .github/agents.

  3. yurideon commented on Nov 19, 2025

    @yurideon

    Thanks for looking into it!

    Having the same problem. Just to add some context, I installed github MCP by pressing the "button" on the README page, which adds

    	"github": {
    		"type": "http",
    		"url": "https://api.githubcopilot.com/mcp/"
    	}
    

    to the mcp.json file.

    And in the same way, "tools": ["github/*"] doesn't work, while "tools": ["github"] allows the agent mode to access github MCP.
    I'm using it with a custom "agent" in .github/agents folder.

    Image
  4. aeschli commented on Nov 19, 2025

    @aeschli

    @connor4312 @sandy081
    We need to encourage user to install MCP servers via the MCP marketplace. The 'Install Server' button should redirect to do that.

  5. JeelRajodiya commented on Nov 24, 2025

    @JeelRajodiya

    For some context, I'm having the same issue with playwright mcp server as well.

    Image

    My mcp.json file:

    Image

    When I create a custom agent, I get these error and I can't use both playwright or github mcp with custom agent.
    But if I use the default agent which comes with copilot, it works without any issues.

    Note that, I don't face any issues while using context7 mcp server

  6. aviita commented on Dec 8, 2025

    @aviita

    So what is the correct naming for the MCP if e.g. we need to get it as docker container from our artifactory? Is it github-mcp-server? And has that been proven to fix this issue?

    Basically the tools picker is also broken for me. If I select tools for a *.chatmode.md, I get to check boxes and e.g. github/search_repositories gets added to my file, but it results to warning in problems:

    Unknown tool 'github/github-mcp-server/search_repositories'.
    The set of tools that the custom agent has access to.

    If a go back to the tools picker, all the github mcp tools are again disabled.

  7. aviita commented on Dec 8, 2025

    @aviita

    So what is the correct naming for the MCP if e.g. we need to get it as docker container from our artifactory? Is it github-mcp-server? And has that been proven to fix this issue?

    Basically the tools picker is also broken for me. If I select tools for a *.chatmode.md, I get to check boxes and e.g. github/search_repositories gets added to my file, but it results to warning in problems:

    Unknown tool 'github/github-mcp-server/search_repositories'.
    The set of tools that the custom agent has access to.

    If a go back to the tools picker, all the github mcp tools are again disabled.

    Yup. Renaming the tool (to github-mcp-server) fixed it. Though it seemed to work earlier just fine (the tools picker did not deselect the tools). Anyways, fine with the rename, just need to let people to know to rename it in their mcp.json...

  8. yashhzd commented on Feb 18, 2026

    @yashhzd

    Hey, I've been investigating this issue and traced the root cause through the source code. I'd like to take a shot at fixing it.

    Root Cause Analysis

    The problem stems from a naming mismatch between the MCP server's Implementation.Name and the config key that VS Code's install button creates.

    Server side (pkg/github/server.go:186-191)

    s := mcp.NewServer(&mcp.Implementation{
        Name:    "github-mcp-server",   // <-- This is what the server reports
        Title:   "GitHub MCP Server",
        Version: version,
        Icons:   octicons.Icons("mark-github"),
    }, opts)

    Client side (VS Code mcp.json)

    When users install via the README button or manually configure, the config typically looks like:

    "github": { "type": "http", "url": "https://api.githubcopilot.com/mcp/" }

    The config key is "github", but the server identifies itself as "github-mcp-server" during the MCP initialize handshake.

    The collision

    When a user writes "tools": ["github/*"] in their agent config:

    1. VS Code sees github/* and tries to resolve it against the MCP server configured as "github"
    2. But the server's Implementation.Name is "github-mcp-server", causing VS Code to construct github/github-mcp-server/*
    3. No tool matches that pattern → "Unknown tool" error

    This also explains why @aviita's workaround of renaming the MCP config key to github-mcp-server fixes it — it makes the config key match the Implementation.Name.

    Evidence from the comments

    • @GordonBeeming confirmed this affects multiple MCPs, not just GitHub — which aligns with this being a general name-mismatch pattern
    • @yurideon confirmed the issue occurs even when installing via the README button (which creates the "github" config key)
    • @aviita confirmed that renaming to github-mcp-server resolved the issue

    Proposed Fix

    I'd like to submit a PR that aligns the server's Implementation.Name with the expected config key. The Implementation.Name field is informational in the MCP protocol (used for display/logging in clients), so changing it should be a safe, non-breaking change.

    I'll also update any affected tests and regenerate docs as needed.

    Would this approach be acceptable? Happy to discuss alternatives if the team has concerns about changing the server name.

  9. added a commit that references this issue on Feb 18, 2026
    ac19dc7
  10. laozhangzzz commented on Jun 25, 2026

    @laozhangzzz

    This one is especially easy for agents to chase in circles because both names appear to be recommended depending on the surface.

    The practical diagnosis I collected is: treat it as a client/toolset naming mismatch, not as a GitHub API/auth failure. In affected VS Code setups:

    • github/* can be reported as unknown
    • github can still work while warning that it was renamed
    • where the client supports it, listing both can be a tactical workaround while the naming transition settles
    • old agent/chatmode locations may not handle the newer aliases the same way newer agent files do

    I wrote the exact-symptom note here:
    https://laozhangzzz.github.io/agent-pitbook/pits/github-mcp-vscode-toolset-name-mismatch.html

  11. aeschli commented on Jun 29, 2026

    @aeschli

    The github and the playwrite mcp server have special short aliases in agent files: github/* and playwrite/*.
    VS Code maps these aliases to the following real mcp server names: 'github/github-mcp-server', 'io.github.github/github-mcp-server', 'github-mcp-server' and tries to find these.
    If not found, it should give a better error message.
    To install these servers in VS Code:

    • there's a built in github server that you can enable with the setting github.copilot.chat.githubMcpServer.enabled.
    • To install from the marketplace, go to the extensions view, type @mcp github. The github mcp server should should up with id io.github.github/github-mcp-server
  12. aeschli commented on Jun 29, 2026

    @aeschli

    I created microsoft/vscode#323411 to improve the experience

  13. github-actions commented on Oct 9, 2026

    @github-actions
    Contributor

    This issue is stale because it has been open for 30 days with no activity. Leave a comment to avoid closing this issue in 60 days.

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