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

Annotations already declare destructiveHint=true and idempotentHint=true, so safety is partly covered, but the description adds genuinely new behavioral facts: the deletion cascades to associated events and cannot be undone. It still omits error behavior (e.g., unknown contactId) and whether the apiKey override is required for this operation.

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 terse sentences with the destructive cascade front-loaded before the irreversibility warning. Every word earns its place and nothing is buried.

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 delete with no output schema, the description covers the essential scope and irreversibility. It would be complete with a note on behavior when the contact does not exist or on dependent records beyond events.

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%, so both parameters (apiKey, contactId) are already documented in the schema. The description adds no format or constraint details beyond that, making the baseline 3 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) plus the cascade scope (all associated events). This lets an agent distinguish it from remove_contact_from_audience or add_suppression, which are non-destructive alternatives in the sibling list.

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 no when-to-use or when-not-to-use guidance and never mentions alternatives such as suppression or audience removal. An agent must infer entirely from the tool name that this is the hard-delete path.

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