agentscope-ai/agentscope · error · ValueError

Cannot find group '{group_name}' in toolkit, only {[_.name f

Error message

Cannot find group '{group_name}' in toolkit, only {[_.name for _ in self.tool_groups]} are available.

What it means

Toolkit.add_tool raises ValueError when the group_name argument does not match any registered tool group. The error lists the available group names so you can see what the toolkit actually knows about.

Source

Thrown at src/agentscope/tool/_toolkit.py:673

                for new_tool in new_tools:
                    if new_tool.name in existing_tools:
                        logger.warning(
                            "Duplicate tool name '%s' found in group '%s', "
                            "overwriting it.",
                            new_tool.name,
                            group.name,
                        )
                        # override the existing tool
                        group.tools = [
                            t for t in group.tools if t.name != new_tool.name
                        ] + [new_tool]
                    else:
                        group.tools.append(new_tool)
                        existing_tools.add(new_tool.name)

                return

        raise ValueError(
            f"Cannot find group '{group_name}' in toolkit, only "
            f"{[_.name for _ in self.tool_groups]} are available.",
        )

    async def remove_tool(self, tool_name: str | list[str]) -> None:
        """Remove tool from the toolkit on-the-fly.

        Args:
            tool_name (`str | list[str]`):
                The name of the tool to be removed.
        """
        if isinstance(tool_name, str):
            tool_name = [tool_name]

        for group in self.tool_groups:
            group.tools = [
                tool for tool in group.tools if tool.name not in tool_name
            ]

View on GitHub (pinned to e90f1c7592)

Solutions

Use one of the group names printed in the error message
Create the group first: add a ToolGroup(name='X', tools=[]) to the Toolkit before add_tool
Guard by checking `[g.name for g in toolkit.tool_groups]` before calling add_tool

Example fix

# before
await toolkit.add_tool(mem_tool, group_name='memory')  # group doesn't exist
# after
toolkit = Toolkit(tool_groups=[ToolGroup(name='memory', tools=[]), ...])
await toolkit.add_tool(mem_tool, group_name='memory')

Defensive patterns

Strategy: validation

Validate before calling

available = [g.name for g in toolkit.tool_groups]
if group_name not in available:
    group_name = available[0]  # or raise with a clear message
await toolkit.add_tool(tool, group_name=group_name)

Try / catch

try:
    await toolkit.add_tool(tool, group_name=group_name)
except ValueError as e:
    # parse available names from e and retry with a valid group

Prevention

Define group-name constants used both when creating groups and when calling add_tool
Create empty target groups up-front in toolkit construction

When it happens

Trigger: Calling await toolkit.add_tool(tool, group_name='X') where 'X' is not among [g.name for g in toolkit.tool_groups]; e.g. 'search' when only a 'default' group exists.

Common situations: Agents adding tools on the fly (e.g. memory tools in ReAct flows) targeting a group name that was never created; typos or case mismatches in group names; assuming a default group name exists when a custom set was passed.

Related errors

AI-assisted analysis of agentscope-ai/agentscope@e90f1c7592 (2026-08-28). Data as JSON: /api/errors/ed83411e7acfad2a. Report an issue: GitHub.