Type text

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

Annotations already declare destructiveHint=true, idempotentHint=false and openWorldHint=true, so the mutation profile is known. The description still adds genuinely new behavior: the clipboard is untouched (unlike paste-based approaches), characters are sent as Unicode so layout is irrelevant, and certain targets silently drop input. It does not say what happens when no control is focused, but the added signal is well above the annotation baseline.

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?

Four short lines, front-loaded with purpose, then prerequisite, then mechanism note, then failure case. Every sentence carries distinct information and none restates the tool name or title.

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?

With an output schema, full annotation coverage and 7 fully described parameters, the description only needs to cover intent, prerequisites and pitfalls, which it does. The one minor gap is not stating the failure mode when nothing is focused or what happens to existing content at the caret position, but the context is otherwise sufficient to call the tool correctly.

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%, so every parameter (record, delay_ms, settle_ms, timeout_ms, until_speech, record_within) is already documented in structured data, setting the baseline at 3. The description contributes only the incidental note that Enter must be pressed separately, matching the text param's single-line constraint, but adds no meaning for the recording or timing parameters.

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 ('Type text into the focused control') and immediately bounds the mechanism ('as if typed on the keyboard, without touching the clipboard'). This clearly separates it from nvda_set_value (value-setting) and nvda_press_keys (keystroke simulation) without needing the schema.

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?

Gives an explicit prerequisite chain ('Focus an edit field first (nvda_find_objects then nvda_focus_object, or nvda_press_keys)') and an explicit exclusion with the alternative to use instead ('Some games and remote desktop windows ignore this kind of input; use nvda_press_keys there'). Both when-to-use and when-not-to-use are covered.

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