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

Annotations already declare destructiveHint and idempotentHint, but the description goes further by disclosing the hidden side effect ("Deleting a Scanner's task tells that Scanner it was wrong") and the retry contract ("a repeat returns the first delete's answer"). That is behavioral context the agent cannot obtain from the annotations or schema.

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?

Four short sentences, each carrying distinct information: what it does, irreversibility plus the alternative, the side effect, then the retry rule. The destructive nature is front-loaded and there is no redundant phrasing.

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 tool with no output schema, the definition covers effect, irreversibility, the sibling alternative, the external side effect, and the retry outcome. The only minor gap is failure behavior on an invalid task_id, which is largely implied by the schema's UUID format.

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 50%: idempotency_key is documented in the schema, task_id only carries format/pattern. The description adds genuine meaning for idempotency_key by explaining the retry-and-same-result semantics, and implies task_id refers to an existing task. It does not clarify task_id's origin or failure behavior when the id is unknown, so it does not fully compensate for the coverage gap.

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?

Specific verb+resource ("Deletes a task outright") with an explicit scope qualifier that separates it from the soft alternatives. It names skip_task as the different tool for the same domain object, so an agent can route between them from the description alone.

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?

States the when-not case explicitly ("to say a task is not needed, use skip_task instead") and frames the call as irreversibility ("cannot be undone"), which is precisely the decision criterion an agent needs. Nothing about alternative selection is left to inference.

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