add_block_rows

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

Beyond annotations (readOnlyHint=false, destructiveHint=false), the description discloses key behaviors: auto-materialization of value_formula fields, auto-installation of validation/editability shadows, and the side effect of inserting sheet rows that shift downstream rows. These are significant behavioral details not captured in the schema or annotations, fully meeting the transparency burden.

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 dense but efficient, covering all essential aspects in three sentences. It front-loads the core purpose and then logically proceeds to positioning, key requirements, engine behavior, and side effects. No fluff or redundancy.

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?

Given the tool's moderate complexity (4 params, no output schema), the description is thorough: it explains default behavior, alternate insertion modes, value constraints, automatic shadow installation, and sheet row impact. The only minor omission is a stated return value, but that is not critical for a write operation and is not required since no output schema exists.

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?

Schema coverage is 75%, so the description adds value by clarifying that rows require a key and values are keyed by field name—though this partly repeats schema. The crucial addition is the caution about value_formula fields ('don't pass them in values'), which is not in the schema. This elevates understanding of the values parameter beyond the basic schema description.

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 'Add rows to an existing block' – a specific verb (add) + resource (block) that clearly distinguishes from siblings like delete_block_rows and move_block_row. It also explains the default append behavior and positional insertion via after_key/before_key, leaving no ambiguity about the tool's function.

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 provides practical guidance: append is default, insertion can be placed with after_key/before_key, and value_formula fields should be omitted. However, it does not explicitly contrast with alternative tools (e.g., set_block_cells) or state when not to use this tool, so it falls short of perfect guidance.

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