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

Annotations already declare destructiveHint=true and idempotentHint=true, so the safety profile is covered; the description goes further by disclosing that deletion is permanent and irreversible here, that contacts are not notified, and how unmatched ids surface as not_found. That is substantive context beyond the structured fields.

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 tight sentences: trigger first, input source and limit second, irreversibility plus the sibling exclusion last. No filler and nothing redundant with the schema.

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 destructive, single-parameter tool with an output schema and full annotation coverage, the description supplies everything an agent needs: when to call it, what to pass, irreversibility, notification behavior, and the sibling it must not be confused with.

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 parameter is fully documented (1–50 ids returned by lemonvite_search_contacts), so the baseline is 3. The description repeats the max of 50 and the provenance of the ids rather than adding new syntax or format constraints.

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 and resource — deleting people from the Lemonvite contact list (address book) — and explicitly contrasts that scope with invitation guest lists. An agent can distinguish it from lemonvite_remove_guests without opening a 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?

Gives the trigger condition ('when the user wants people deleted from their contact list') and an explicit exclusion with the correct alternative ('does not take anyone off an invitation's guest list; use lemonvite_remove_guests for that'). It also names the upstream tool that supplies ids.

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