OpenBB-finance/OpenBB · error · ValueError

No tools found in '{category}'/'{subcategory}'. Available ca

Error message

No tools found in '{category}'/'{subcategory}'. Available categories: {', '.join(sorted(available))}

What it means

Raised by the MCP server's category-activation tool when the category (or category/subcategory pair) resolves to zero tool names, meaning nothing can be activated for the session. This happens when the category key is wrong or when a valid category exists in the index but has no tools registered (extension installed but not exposed). The message lists available categories.

Source

Thrown at openbb_platform/extensions/mcp_server/openbb_mcp_server/app/app.py:724

        @mcp.tool(tags={"admin"})
        async def activate_category(
            category: Annotated[
                str, Field(description="Category name to activate all tools for")
            ],
            ctx: Context,
            subcategory: Annotated[
                str | None,
                Field(description="Optional subcategory to narrow activation"),
            ] = None,
        ) -> str:
            """Activate all tools in a category (or subcategory) for this session."""
            if subcategory:
                names = category_index.get_subcategory_names(category, subcategory)
            else:
                names = category_index.get_category_names(category)
            if not names:
                available = list(category_index.get_categories().keys())
                raise ValueError(
                    f"No tools found in '{category}'"
                    + (f"/'{subcategory}'" if subcategory else "")
                    + f". Available categories: {', '.join(sorted(available))}"
                )
            await ctx.enable_components(names=names)
            scope = f"'{category}'" + (f"/'{subcategory}'" if subcategory else "")
            return (
                f"Activated {len(names)} tools in {scope}"
                f": {', '.join(sorted(names))}"
            )

    # Expose prompts and resources as tools via transforms so that
    # tool-only clients can list/render prompts and list/read resources.
    mcp.add_transform(PromptsAsTools(mcp))
    mcp.add_transform(ResourcesAsTools(mcp))

    @mcp.tool(tags={"resource", "admin"})
    async def install_skill(

View on GitHub (pinned to 3e071fcc2c)

Solutions

Use an exact category from the 'Available categories' list in the error message.
If the category is right but empty, check your MCP/OpenBB config for route exclusions and re-enable the extension's routes.
Verify the extension is installed and loaded (list_categories) before activating.
For subcategory activation, confirm the subcategory key with the listing tool first.

Example fix

# before
msg = await activate_category(category="nonexistent")

# after
available = (await list_categories()).keys()
msg = await activate_category(category=next(c for c in available if "equity" in c))

Defensive patterns

Strategy: validation

Validate before calling

async def activate_category_safe(mcp_client, category: str):
    cats = await mcp_client.call_tool("list_categories", {})
    names = {c["name"] for c in cats.result}
    if category not in names:
        raise ValueError(f"{category!r} not in available categories: {sorted(names)}")
    return await mcp_client.call_tool("activate_category", {"category": category})

Type guard

def is_activatable(category: str, subcategory: str | None, index_names: list[str]) -> bool:
    return bool(index_names) and category in {n.split("_")[0] for n in index_names}

Try / catch

try:
    msg = await activate_category(category=cat)
except ValueError as e:
    if "No tools found in" in str(e):
        # category exists but is empty or wrong: fall back to listing then activating by exact name
        tools = await list_category_tools(category=sorted(category_index.get_categories())[0])
    else:
        raise

Prevention

Confirm the category yields tool names via the listing tool before activating.
Check MCP route-exclusion config if a category unexpectedly activates zero tools.
Log the available-categories list from the error to self-heal bad inputs.

When it happens

Trigger: Calling activate_category(category='crypto', subcategory='invalid') where the subcategory miss yields an empty name list; activating a category whose extension is installed but whose routes were excluded from MCP exposure via config; typos in category.

Common situations: MCP clients bulk-activating tool groups by name; OpenBB MCP config excluding routes (expose: false) so a category index exists but is empty; stale category names after upgrades.

Related errors

AI-assisted analysis of OpenBB-finance/OpenBB@3e071fcc2c (2026-08-14). Data as JSON: /api/errors/223e2d80dec1218e. Report an issue: GitHub.