read_variables

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

With no annotations, the description carries the full burden. It usefully discloses vectorized numeric reads, string coercion for text, and null for missing values, which is real behavioral context. It omits any statement about side effects, permissions, or the effect of the `attach` parameter (which implies live-editing an app), leaving gaps for a tool that can touch a running process.

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?

Three short, front-loaded sentences with no filler; the core action comes first and the type-handling caveats follow. Nothing is wasted, though the content is minimal rather than rich.

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 6-parameter read tool with no annotations and no output schema, the description covers value semantics (vectorized, strings, nulls) but says nothing about the shape of the returned data or how to interpret it. Adequate but leaves an agent guessing about the result structure.

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 description coverage is 100%, so all six parameters are already documented in the schema. The description adds no parameter-level syntax or format detail beyond that baseline.

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?

States a specific verb+resource ('Read variable values') that clearly separates it from write-oriented siblings like write_variables and add_variables. It does not, however, explicitly distinguish itself from describe_spreadsheet or describe_analysis, which an agent might reasonably confuse with reading values.

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 explains the mechanics of reading but gives no guidance on when to use this tool versus alternatives such as describe_spreadsheet, list_sheets, or export_csv. No prerequisites, no exclusions, no context cues.

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