key

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

Annotations already declare destructiveHint=true and openWorldHint=true, so the description's burden is lower, yet it adds nothing about effects — that a chord like ctrl+alt+delete can alter or lock system state, or what happens if the target window lacks focus. The examples are format guidance, not behavioral 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?

A single front-loaded sentence with compact, high-value examples and no filler. Every token earns its place.

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 one-parameter tool with no output schema this is close to sufficient, but it omits where the keypress lands (focused window), platform-specific key names, and how it differs from typing text. Those gaps matter for correct invocation.

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 0% and "chord" has no type-level description, so the description carries the load by demonstrating the expected syntax ("win+r", "ctrl+a", "ctrl+alt+delete", "enter"). That is a meaningful addition beyond the bare string schema, though modifier ordering and valid key names are never stated.

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 gives a concrete verb+resource ("Press a key or chord") and illustrates with real chord forms. It does not, however, distinguish this from the sibling "type" tool, so an agent must infer that "type" writes text while "key" emits a single keystroke or combination.

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?

Usage is only implied by the examples; there is no explicit statement of when to call this versus "type" or when a chord is inappropriate. An agent can reasonably infer the intent, but nothing routes it away from the wrong sibling.

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