excel_open_workbook

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations provided, the description must carry the behavioral burden. It discloses the side effect 'Launches Excel if not running,' but it fails to mention other important behaviors such as what happens if the file is already open, error handling for missing files, or whether the workbook becomes the active window.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is extremely concise, consisting of two succinct sentences. It is front-loaded with the primary action and adds the key side effect in the second sentence with no unnecessary wording.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Although the schema fully describes the parameter, the description lacks crucial context such as what the tool returns (if anything), how it relates to sibling tools (e.g., after opening, use other tools to manipulate the workbook), and error handling. This incompleteness can confuse an agent about the workflow.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The schema description coverage for the single parameter 'file_path' is 100%, fully describing it as an absolute path to .xlsx/.xlsm/.xls files. The tool description adds no additional meaning beyond the schema, so the baseline score of 3 is appropriate.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the action ('Open a workbook file') and the resource ('workbook file'). It also mentions the side effect of launching Excel if not running. Among sibling tools like excel_read_cell and excel_save_workbook, this tool's purpose is distinct and unambiguous.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description does not provide explicit guidance on when to use this tool versus alternatives, such as excel_list_workbooks for already opened files or excel_save_workbook for saving. There is no mention of prerequisites (e.g., ensure file exists) or when not to use it.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.