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

The annotations already set destructiveHint=true and readOnlyHint=false, so 'this is destructive' adds no new information. The description does add the useful caveat that explicit confirmation is required before deletion, though 'Side effects: deletes contact' largely restates the purpose. No contradiction with 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?

The first sentence repeats the tool title, the second repeats destructiveHint, and the final 'Side effects' line repeats the first sentence. Only 'requires explicit confirmation' is non-redundant, so the description does not satisfy the requirement that every sentence earn its place.

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, destructive operation with a rich input schema, an output schema, and safety annotations, the description is nearly sufficient: it identifies the action and the key precondition of explicit confirmation. It does not need to explain return values because an output schema exists; only minor edge-case context is absent.

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%, and both contact_id and confirmation_text are already documented with clear descriptions, including the exact required value for confirmation_text. The tool description adds no parameter-level detail beyond those structured definitions.

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 names the exact action and resource ('Delete a contact'), which is unambiguous against siblings like delete-contact-group and delete-fax. It does not explicitly contrast those siblings, but the resource term is specific enough that the tool's purpose is clear.

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 implies the intended use—when a contact must be removed—and warns that explicit confirmation is required. It does not state when not to use this tool or mention any alternative deletion/update tool, so the agent must infer selection choices from context.

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