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

Annotations already declare destructiveHint=true, idempotentHint=true and readOnlyHint=false, so the safety profile is covered structurally. The description adds the ownership scoping constraint, which is genuine value beyond annotations, but it says nothing about irreversibility, cascade effects on contact notes or interactions, or authorization failures. For a destructive tool that is a meaningful gap, though the lower bar applies given rich annotations.

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?

One short sentence with the scope qualifier attached directly to the verb. Nothing is padded and the key operation is front-loaded.

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 one-parameter destructive tool with full annotation coverage, the essentials for invocation are present: the operation, the id, and the ownership restriction. Missing are what 'delete' actually means here (hard vs soft delete, effect on related contact notes and interactions), which an agent making a destructive call would reasonably want.

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% with a single required 'id' string already documented in the schema. The description adds no format, source, or lookup guidance for the id (e.g. obtainable from contact_list/contact_search), so it contributes nothing beyond the structured field. Baseline 3 is appropriate.

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 (delete) and resource (contact) in a single clear sentence, which separates it from contact_note_delete and contact_update. It stops short of any explicit sibling differentiation, but the resource noun is unambiguous.

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 phrase 'you own' is an implied precondition that narrows when this tool applies, which is useful. There is no explicit guidance on alternatives (e.g. contact_update to modify, contact_read to verify) or when not to delete.

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