mc_key

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

With no annotations, the description carries the full behavioral burden. It usefully discloses that the press behaves like a genuine key event in both gameplay and GUI screens, but omits whether the call blocks, whether the game window must be focused, and what happens if an invalid key name is supplied.

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?

Two sentences, zero filler. The core action and its argument domain come first, and the behavioral note about in-game and screen contexts follows immediately.

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 three-parameter input tool with a fully documented schema and no output schema, the description covers the essential what and how. The only meaningful gap is sibling disambiguation against mc_type and mc_hotbar.

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 the baseline is 3. The description does extend the 'key' parameter beyond the schema's examples ('escape', 'e', 'f3') with arrows, f1-f12, space, letters and digits, but it says nothing about 'mods' or the 'action' enum (press/down/up), leaving that entirely to the schema.

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 ('Press a key') and enumerates the accepted key namespace (escape, enter, tab, f1-f12, letters, digits), so the agent knows exactly what input class this handles. It does not explicitly distinguish itself from siblings like mc_type or mc_hotbar, which keeps it just below a 5.

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 implied only: the description says it emulates a real key press in-game and in screens, which suggests when it applies, but never states when to prefer mc_type (text entry) or mc_hotbar (hotbar slots) instead. No prerequisites such as window focus or an open screen are mentioned.

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