key_type

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

With no annotations, the description carries the full burden. It discloses that it uses SendKeys, that text is escaped automatically, that keys are raw, and that input goes to the focused window. It also mentions the delay_ms behavior. However, it doesn't mention potential side effects (e.g., typing into an unexpected window if focus is lost) or error conditions, which would make 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?

The description is a compact paragraph front-loaded with the core purpose, followed by the prerequisite, then the two modes with examples. Every sentence adds value: purpose, focus guidance, text mode, keys mode, and a sample usage. No wasted words.

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 complexity (three params, no annotations, no output schema), the description covers the essential usage, examples, and a prerequisite. It's missing some edge-case details (e.g., behavior if no window is focused, how special characters are escaped) but still provides enough for an agent to invoke it correctly. A 5 would require more on failure modes or return behavior.

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%, so baseline is 3, but the description adds substantial meaning: it explains the precedence of 'keys' over 'text', provides concrete examples for both parameters, and gives guidance on delay_ms values (50-100 for stable typing). This goes well beyond the schema descriptions.

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 clearly states the tool types text or sends keystrokes to the focused window using PowerShell SendKeys. It uses a specific verb ('type'/'send'), names the resource ('currently focused window'), and distinguishes itself from sibling tools like run_command and clipboard_set by focusing on keyboard input.

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 an explicit prerequisite: 'Call window_focus first to make sure the target window is active.' It also explains when to use 'text' vs 'keys' with examples. However, it doesn't explicitly mention when NOT to use this tool or name alternatives (e.g., using clipboard_set for large text), so it falls short of a 5.

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