Type into a TextBox

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

Annotations already declare destructiveHint=true and idempotentHint=false, but the description goes well beyond them: it flags 'WRITES LIVE GAME STATE', discloses the VirtualInputManager mechanism and keypress/keyrelease fallback, explains the side effect that text-changed and FocusLost handlers fire, notes focus capture/release, and states the exact failure/verification path. This is unusually rich behavioral context for a mutation tool.

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?

Front-loaded with the critical 'WRITES LIVE GAME STATE' warning and the core behavior, then organized into mode guidance, signature, phase/requires/capabilities, and safety. Some metadata (the full signature, 'Safety: MUTATING') restates schema or annotations, so it is slightly longer than strictly necessary, but every block is scannable and earns most of its space.

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?

Despite no output schema, the description states the return shape ({ Path, ok } or { error }), names the verification tool (get-gui-text), lists required preconditions, and covers both operating modes. For a 5-parameter mutation tool, nothing an agent needs to call it correctly is missing.

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 the baseline is 3, but the description adds meaning beyond the schema: it explains *why* useKeyPress matters (handler firing vs. fast poke), mentions the fallback mechanism, and summarizes the full signature including optional enter/threadContext. Only threadContext gets no extra treatment beyond the schema's default note.

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 a specific verb and resource ('Enter text into a Roblox TextBox by path') and then distinguishes its two operating modes, which separates it from siblings like set-gui-text (direct property write) and press-key/virtual-input (raw input). An agent can identify the tool's job without opening 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?

It gives explicit mode-selection guidance: 'Use the keystroke path when scripts react to player typing; use the direct path for a fast value poke.' It also lists prerequisites (active-client, resolved-target, explicit-mutation-approval) and a verification tool. It does not, however, name sibling alternatives such as set-gui-text or press-key for cases where this tool is the wrong choice.

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