merge_cells

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

No annotations are provided, so the description must carry the full disclosure burden. However, it only lists parameters and states a success return. It does not disclose that merging cells may overwrite existing data, is irreversible, or requires specific permissions. This is a basic operational description without behavioral caveats.

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 well-structured with Args and Returns sections. It front-loads the purpose and then systematically defines each argument. The 'Returns: Success message' is a slight redundancy given the output schema, but it is concise and not excessive.

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?

For a 7-parameter tool with no annotations and an output schema, the description covers the operation and all parameter details effectively. It lacks behavioral context like side effects or permission requirements (which lowers this score), but it is otherwise adequate for an agent to understand what arguments to pass and what to expect.

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 input schema has zero description coverage (only titles), but the description fully explains every parameter: spreadsheet_id, sheet_id, row/column indices (including 0-based and exclusive end values), and merge_type options. This is exactly the semantic richness needed for correct invocation.

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 opens with 'Merge cells in a range.' which is a specific verb+resource statement, clearly distinguishing this operation from sibling tools like write_cells or format_cells. It is not a tautology and immediately tells the agent what the tool does.

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 implies usage (when you need to merge cells in a spreadsheet) but provides no explicit guidance on when to use this tool versus alternatives like format_cells or sort_range. There are no exclusions or prerequisites mentioned, so it only meets the 'implied usage' level.

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