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

Annotations already declare readOnlyHint=false, idempotentHint=true and destructiveHint=false, so the description's job is to add context, which it does: the note persists with the brand and applies to every future post, and Suara retains the 8 most recent notes (implying older ones are dropped). It does not say whether the owner can review, edit, or remove a note later, which is the remaining behavioral gap.

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?

Three sentences, front-loaded with the trigger condition, then persistence behavior, then the sibling alternative. Every clause carries information the agent needs; there is no filler.

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, non-destructive write with no output schema, the description covers trigger, durability, retention limit, and the sibling routing. Only minor lifecycle details (whether saved notes can be listed, edited, or deleted) are absent.

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%, so the baseline is 3; the description earns above that by showing what a well-formed note looks like ('less pink', 'never use emojis') and indicating the owner's own phrasing, which guides content selection beyond the schema's 'short, in the owner's words'. It does not restate the 160-character cap, but the schema already does.

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 and resource (saving a lasting style note) and pins down scope: it applies to all future posts and is stored with the owner's brand. The examples ('less pink', 'more premium', 'never use emojis') make the resource concrete, and it is clearly distinguished from request_post_change.

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 trigger condition ('when the signed-in owner gives a lasting correction for all their future posts') and names the alternative with the condition that selects it ('For a change to one post, use request_post_change'). The durable-vs-one-off split is fully resolved without inference.

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