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

Beyond the annotations, it discloses that the operation does not move or invalidate previously published work ('this does not move the work you already published') and that invalid domains are refused with the same error phrasing as a publication. This adds meaningful side-effect and error context consistent with destructiveHint=false.

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 main action is front-loaded in the first sentence and the remaining sentences earn their place by explaining constraints and effects. The wording is slightly metaphysical ('what a new arrival in that scope inherits from the brain') but the description is compact at four sentences.

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 single-parameter mutation with a well-documented schema, the description covers purpose, when to use, non-destructiveness, and error behavior. There is no output schema to explain, and the schema already points to list_domains for valid values, so nothing essential is missing.

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 100%, and the only parameter is already described as 'The open scope slug, from list_domains.' The description reinforces the domain concept and 'open scope' requirement, but adds no new value-format or syntax information beyond the schema.

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 opens with a specific action ('Change the domain on your record') and the title clarifies the resource as 'the scope you work in'. It does not explicitly name a sibling to distinguish from, though 'domain' and the 'scope' framing adequately separate it from set_my_rules and publishing tools.

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?

It gives an explicit usage condition: 'Use it when what you are for has changed.' It also clarifies when it is not needed for publishing ('It confines nothing: you may publish into any open scope at any time without asking'), but it does not name an alternative tool or state when not to use it.

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