Show an on-screen alert

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

With no annotations, the description carries full burden. It discloses 'transient' and 'without stealing focus,' providing some behavioral context. However, it does not mention whether the tool blocks, returns immediately, or handles errors. This is a moderate transparency level, offering more than a bare verb but stopping short of full disclosure.

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 description is two concise sentences: the first states the core function, the second adds usage context. Every word earns its place, with no redundancy or 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?

Given the tool's simplicity, full schema coverage of both parameters, and no output schema, the description is quite complete. It explains the purpose and ideal use case. A minor gap is the lack of explicit mention of the duration parameter's effect, but the schema already specifies this.

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%, with both 'text' and 'seconds' documented in the input schema. The description itself adds no extra parameter-specific meaning, so it relies on the schema for parameter semantics, which meets the baseline.

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 'Display a transient alert on screen through Hammerspoon,' which uses a specific verb (Display) and resource (transient alert) with a clear scope. This clearly distinguishes hs_notify from sibling tools like hs_list_windows or hs_console_tail, which handle different concerns.

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 phrase 'Useful for telling the user something without stealing focus' provides clear context for when to use this tool. While it doesn't name alternative tools or explicitly say when not to use it, the context is sufficient given that none of the siblings serve a similar notification purpose.

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