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

Annotations already declare this is a non-read-only, non-idempotent, non-destructive operation, so the safety profile is covered. The description adds genuinely useful context beyond them: ownership is required, the ticket is billed to the item's owner, and the ticket is scoped as read-only access. It stops short of saying that repeated calls mint additional distinct tickets or what the returned artifact looks like.

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, front-loaded with what the tool produces, followed by the requirement and billing consequence. Every clause carries information; nothing is redundant.

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 three-parameter mutation with no output schema, the description covers purpose, precondition, cost attribution, and the optional modes, which is enough to call it correctly. It omits what is returned (a ticket string) and how that ticket is later consumed, which would have made it fully self-contained.

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% (uses, ttl_hours, owner_ticket all documented with formats and bounds), so the schema carries the load and a 3 is the baseline. The description's 'single-use or shorter-lived' phrasing loosely maps to uses/ttl_hours but adds no syntax or constraints beyond what the schema already states.

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 concrete verb and resource ('Make an extra read ticket for an item you own') and scopes it with 'extra', which separates it from the plain read path. It does not name any sibling (e.g., anthill_retrieve or anthill_extend) or explain how a share ticket differs from a retrieval, so sibling differentiation is left implicit.

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 the essential precondition (the caller must own the item, and the owner_ticket is required) and notes the optional single-use/shorter-lived modes. It offers no when-to-use guidance relative to alternatives such as retrieving directly, extending, or rotating keys, and no exclusions.

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