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

Beyond the annotations, the description explains that contacts stop receiving campaigns and automated emails, consent history is retained, already-unsubscribed contacts are unchanged, and re-adding requires consent. It also describes the confirmation flow in detail, including the first-call no-op and confirmToken follow-up, which is critical for a destructive 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?

The purpose and scope are front-loaded, and the confirmation flow is explained efficiently in a second paragraph. It is appropriately sized for a destructive tool with a two-step confirmation mechanism, though some sentences are dense and repeat details already present in 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 mutation with three parameters and no output schema, the description covers what changes, what is preserved, how many contacts are affected, response counts, and the confirmation protocol. An agent has enough context to invoke it correctly and safely.

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 the schema already documents all three parameters. The description repeats the contactIds source and the confirmToken confirmation rule, but does not add substantial parameter-level meaning beyond what the schema and annotations already provide.

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 first sentence states a specific verb and resource: "Unsubscribe up to 100 contacts, by the contactIds findContacts gives." It also names the source of the IDs, so an agent can distinguish it from related contact tools such as findContacts or updateContact.

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 a clear guardrail: "do it only when the person asked for these contacts by name or by a filter they chose." It also clarifies that already-unsubscribed contacts stay as they are. It does not explicitly compare this tool to a sibling alternative for contact changes, so it falls just short of the top score.

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