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

The annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false, and openWorldHint=false, so the safety profile is fully covered. The description adds value beyond those: the minimum/maximum number of tools, that aspects falls back to cadence/features/verdict, and that legacy parameter shapes are tolerated – useful behavioral context for correct invocation.

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?

Two tight sentences with no filler; the core purpose and compared dimensions come first, with the defaults and legacy-input caveat after. Slightly dense with comma-separated clauses, but each sentence carries information an agent can act on.

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?

An output schema exists, so the return shape need not be described, and the description covers what dimensions are compared, how many tools are accepted, and the aspect defaults. The remaining gap is that the enum meanings of aspects (e.g., what exactly 'verdict' contains) are only named, not explained, but that is a minor omission given the structured fields.

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 the baseline is 3, and the description earns an increment by restating the defaults for aspects and explicitly flagging that tool_a/tool_b are legacy aliases for the tools array. That legacy note in particular clarifies a non-obvious parameter relationship that the schema only hints at.

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 (compare) and resource (2–4 AI coding tools) and enumerates exactly what is compared: release cadence, feature-matrix differences, recent changes, and per-pair editorial verdict. It does not explicitly name or exclude the sibling tools (cadence_stats, feature_adoption) that overlap with individual aspects, so the differentiation is implied rather than stated.

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 gives partial guidance: the 2–4 window for tools, the default aspects list, and the note that legacy tool_a/tool_b inputs still work. However, it never says when to pick this multi-aspect comparison over single-purpose siblings like cadence_stats or feature_adoption, leaving the selection decision to inference.

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