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

Going well beyond the annotations (which only declare non-read, non-destructive, idempotent), the description explains what alerts actually are (short email plus Slack/Teams/webhook notices), that muting never hides or deletes notes and they still appear in check_notes and must be mentioned in chat, and that mute_all self-expires. This is rich, consequential behavioral context for a settings mutation.

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?

Front-loaded with purpose, then a long but well-organized action list; the trailing block_friend disambiguation is deliberate and earns its place. The single dense sentence listing all actions is harder to scan than a bulleted list would be, which keeps this from a 5.

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 7-parameter, action-dispatching settings tool with no output schema, the description covers scope, the meaning of alerts, the muting contract, action semantics, and the sibling boundary. Nothing an agent would need before invoking it 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 every parameter is already documented in the schema, so the baseline is 3. The description still adds value by tying parameters to actions in prose ('handle, a friend'; 'minutes, or until: a date and time with its UTC offset') and noting quiet hours can run past midnight, which the schema's end description implies but does not state as clearly.

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+resource (change alert settings) and enumerates every action the tool performs (show, mute_friend, unmute_friend, mute_all, unmute_all, set_quiet_hours, clear_quiet_hours). It explicitly distinguishes itself from sibling block_friend: 'To stop someone sending notes at all, that's block_friend, not this.'

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 clear context ('Only when your person asks') and explicitly routes an adjacent need — stopping notes entirely — to block_friend. It does not, however, explain when to prefer mute_all over set_quiet_hours, leaving the agent to infer the distinction between a temporary pause and a recurring daily window.

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