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

Annotations already declare non-readOnly, idempotent, non-destructive, closed-world. The description adds a genuinely useful behavioral trait not in the annotations: 'Only the fields you pass change,' i.e. partial-update semantics, which tells the agent omitted fields are preserved. It does not describe permissions or the response shape, but for a mutation tool with annotation coverage this is solid.

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 sentences, front-loaded with what the tool changes before the exclusions. Every clause earns its place, and there is no redundant restatement of the title or 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 mutation tool with no output schema and full annotation coverage, the description covers scope, partial-update behavior, and out-of-scope tasks. It is complete enough to invoke correctly; only permission/auth requirements are left implicit, which annotations largely neutralize.

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 every parameter already carries its own description and enum. The description restates the affected fields (frequency, digest timing, severity, everyRun) but adds no syntax or format detail beyond the schema, so the baseline of 3 applies.

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 states a specific verb ('Change') and resource (alert settings) and enumerates the affected dimensions: send frequency, digest timing, minimum severity, and every-run emailing. It is easy to separate from get_alert_settings via the verb, but it does not explicitly differentiate itself from near-neighbors like update_check_settings or update_site_settings.

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 strong when-not-to-use guidance by naming tasks that are out of scope and belong in the dashboard: recipient configuration (address, Slack, webhooks), muting sites or monitor types, and turning email alerts off. It stops short of pointing to a specific alternative tool for those tasks, but the boundary is unambiguous.

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