open_chat

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It mentions a permission precondition, which is useful, but doesn't disclose any behavioral side effects (e.g., does it focus a window, create a UI state, require a status check first?). The prerequisite note adds some value beyond what structured fields provide.

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?

A single concise sentence, zero waste, front-loaded with the core action. This is appropriately minimal for a simple tool.

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?

The output schema exists but isn't shown in detail, so the description needn't explain return values. The permission precondition is mentioned, but for a tool with no annotations and a critical prerequisite, the description could go further—e.g., how to verify permissions or what error behavior occurs when they're absent. It's adequate but leaves meaningful gaps for a state-dependent UI action.

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 0%, but there's a single optional 'backend' parameter with an enum (auto/pydirectinput/pyautogui). The description doesn't add context about what 'backend' means or how the choice affects behavior, which would help. However, with one optional parameter with a clear enum, the schema largely speaks for itself, keeping the gap small.

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 verb+resource construct 'Open Sky chat' clearly states what the tool does, and the constraint 'when both input and chat permissions are enabled' indicates a precondition. However, it doesn't clearly distinguish from siblings like send_chat (though the distinction is implied by 'open' vs 'send').

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 mentions a precondition ('when both input and chat permissions are enabled') but doesn't tell the agent how to check those permissions or what to do if they aren't enabled. There's no guidance on when to use open_chat vs send_chat, and no mention of alternatives or exclusions.

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