look

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

With no annotations, the description must carry the behavioral burden. It discloses what is returned (a PNG plus board info) and the scope ('everything visible', or one layer), which tells the agent this is a visual read rather than a mutation, but it never states read-only safety explicitly, says nothing about image size limits despite the max_size parameter, or about latency/rate behavior.

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 tight sentences, front-loaded with the primary action and return value, followed by the invocation trigger. No filler or redundant restatement of the tool name.

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 parameterless-required, read-only capture tool with no output schema, the description adequately explains what comes back (image plus board metadata). The remaining shortfall is the undocumented transparent/max_size behavior, which the agent must infer from the schema.

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 75%, so the schema already documents layer, max_size, and include_reference; the description only echoes the layer option ('or one layer') and adds nothing about max_size or the transparent flag, which has no schema description at all. Baseline 3 is appropriate given the schema does most of the work and one parameter remains undocumented anywhere.

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 states a concrete verb and resource: returns a rendered PNG of the board's visible content plus board metadata (size, layers, drawing space, units), and notes the single-layer variant. It differentiates itself from modeling siblings by being a visual capture, though it does not explicitly distinguish itself from closer siblings like board or export.

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 an explicit trigger condition - 'Use this whenever the user says "look at this"' - which is clear context for invocation. It stops short of naming alternatives or exclusions (e.g., when to prefer export or board instead), so there is a gap at the 5 level.

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