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

The annotations already establish that this is a read-only, non-open-world listing. The description adds useful behavior-adjacent context, "Also counts per gate", but does not describe ordering, pagination, or response structure.

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 front-loaded with the core action and is only two sentences. It slightly duplicates the schema's enum list, which is redundant but not harmful.

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 simple read-only listing tool with full schema coverage and annotations, the description is largely complete: it gives the resource scope, filter values, and mentions per-gate counts. It could be stronger by clarifying how it relates to the sibling lookup tool.

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 100%, and the single gate parameter is fully documented by the schema enum and "Filter; omit for all". The description repeats the enum values but adds no filtering semantics beyond the schema.

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 states a specific verb and resource: "List the 58 tested services", and notes optional gate filtering. It does not explicitly differentiate the tool from sibling lookup_signup_gate, so it stops short of a 5.

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?

It says the gate filter is optional and the schema clarifies omitting it returns all, which implies usage. However, it gives no explicit when-to-use guidance and does not mention the sibling lookup_signup_gate alternative.

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