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

Annotations already declare destructiveHint=true, but the description adds genuinely non-obvious behavior: disabling removes DNS records while retaining config, enabling re-creates them, and only enabled subdomains count toward the per-tier limit. It does not cover error conditions (e.g., limit exceeded) or whether the DNS removal is immediate/propagated.

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 sentences, no filler, front-loaded with the action and immediately followed by the consequential side effects and quota rule. Every sentence adds information an agent needs.

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 two-parameter mutation with no output schema, the description covers what changes and the quota implication. It stops short of stating failure modes (tier limit exceeded, unknown subdomain_id) and whether the call returns the updated state, which would fully close the loop.

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% with only two parameters, so the schema already documents both fields; the description adds no syntax or format detail beyond the boolean semantics the schema states. Baseline 3 is appropriate when the schema does the heavy lifting.

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 pair ('enable or disable') and resource ('a subdomain'), matching the title and clearly separable from siblings like register_subdomain, delete_subdomain, and check_subdomain. An agent can tell what state change this performs without opening the schema.

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 effects of each direction but never states when to use this over register_subdomain/delete_subdomain or what prerequisites apply (e.g., subdomain must exist, tier limit reached). Usage is implied by the effects rather than explicitly routed against alternatives.

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