Screenshot

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It only says it's an alias and gives no information about what the tool does, its side effects, required permissions, return format, or any other behavior. This is a complete absence of behavioral context.

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 single short sentence, but it is under-specified rather than concise. It omits essential information about the tool's functionality and parameters, so it is not appropriately sized for an agent to use effectively. The structure does not front-load any useful content beyond the alias statement.

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?

Even for a simple tool with one optional parameter, the description is grossly incomplete. It doesn't state what the tool does, what it returns, what the parameter does, or when to use it. With no output schema and no annotations, the agent has virtually no information to correctly invoke this tool.

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?

The schema has one parameter ('device') with zero description coverage. The description does not mention this parameter at all, so the agent gets no explanation of what 'device' means or how to use it. The description fails entirely to compensate for the schema's lack of documentation.

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 identifies the tool as an alias of get_screenshot, implying it serves the same purpose as that tool. However, it does not explicitly state what the tool does (e.g., capture a screenshot), relying on the agent to know get_screenshot's behavior. It does differentiate from siblings by labeling it an alias, but the purpose is not self-contained.

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 phrase 'kept for existing clients' hints that new clients should use get_screenshot instead, providing a usage condition. However, it doesn't elaborate on when to use this tool vs. other screenshot-related siblings like perceive_screen or read_screen, leaving the guidance minimal.

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