press_key

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

Annotations only declare readOnlyHint=false and openWorldHint=true, so the description earns credit for disclosing the specific side effect that matters: Enter can submit a message. It also documents the human-approval gate behind confirmed=true, which is exactly the kind of context annotations cannot carry. It does not cover other possible key-triggered actions or failure modes.

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, no filler, with the core action and examples front-loaded and the confirmed=true rule following immediately. Every sentence adds information the agent needs.

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 three-parameter, open-world mutation tool with no output schema, the definition covers the key format, the hazard case, and the approval requirement — enough to invoke it correctly. Minor gaps remain around unsupported keys or how errors are surfaced.

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 0%, so the description must compensate and largely does: it defines the key parameter's format through examples including a modifier chord, and explains that confirmed is an approval flag tied to the submit case. Only session_id is left unexplained, and its purpose is self-evident from the sibling session tools.

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 gives a specific verb and resource ("press a key on the page") and illustrates it with concrete examples ("Enter", "Escape", "Tab", "Control+A"), which implicitly separates it from text entry via type_text. It stops short of naming siblings or stating the boundary explicitly, so it lands just below the top tier.

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 supplies a genuine conditional rule: Enter in a message box usually submits, so confirmed=true is required once the user approves. That tells the agent when the risky path applies. It does not contrast with alternatives such as type_text, click, or select_option, so it is clear context without exclusions.

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