Type text

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

With no annotations, the description carries the full burden and discloses key traits: US layout, escape sequences for Enter/Tab, non-ASCII rejection, and a critical security risk of typing into a password field. It still leaves some behavior unstated (e.g., whether text requires an already-focused field, what happens on failure), keeping it short of a 5.

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 tight sentences, each carrying distinct value: purpose, input constraints, and safety prerequisite. There is no filler, and the critical constraint is front-loaded after the purpose statement.

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 simple 2-parameter tool with no output schema, the description covers the essential context: what it does, format constraints, and a safety check. It is nearly complete but omits return behavior and focus requirements, which are minor gaps for this tool type.

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 50% because the required 'text' parameter has no schema description. The description compensates by explaining escape sequences and the ASCII-only constraint for that parameter, adding meaningful semantics beyond the schema. It does not elaborate on delay_ms, which the schema already documents.

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?

States a specific verb and resource: 'Types text on the host keyboard'. The scope is clear, but it does not distinguish itself from the sibling press_keys tool, which likely also sends keyboard input, so an agent must infer which one applies to string typing versus key combos.

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?

Provides a concrete prerequisite ('Take a screenshot first') tied to a real failure mode (locked screen), which is clear usage context. It does not, however, state when to prefer this over press_keys or other input tools, leaving the alternative implicit.

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