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

With annotations already declaring readOnlyHint=false, destructiveHint=false and idempotentHint=true, the description adds genuinely new behavioral context: the effect is permanent ('forever') and no key/auth is required. It does not say whether the opt-out is reversible, which matters given the permanence claim, so it is not fully transparent.

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 short sentences, zero filler, with the core action and its permanence front-loaded ahead of the auth note. Nothing could be trimmed without losing information.

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 low-complexity two-parameter tool with a fully described schema and no output schema, the description supplies the essentials: what is affected, that it is permanent, and that no key is needed. The only material omission is whether the opt-out can later be undone.

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 'domain' and 'reason' are documented in the schema itself and the description adds no syntax, format, or semantic detail beyond what is already there. Baseline 3 applies when the schema carries the load.

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 (opt a domain out of Haven outreach) with the scope of effect stated as 'any Haven outreach, forever'. It clearly distinguishes itself from generic contact/block-style tools in principle, but never names or contrasts any sibling such as block_agent, so an agent must infer the boundary.

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?

Usage is implied by the name and by 'opt a domain out' — an agent can infer you call it when you want a domain to stop receiving outreach. There is no explicit when/when-not guidance and no mention of the alternative to use when you only want to silence one agent rather than a whole domain.

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