screenshot

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

With no annotations and no output schema, the description carries the full burden of explaining behavior. It discloses that the result is a JPEG screenshot of the current tab, but does not say how the image is returned (e.g., path vs. data URL), whether it captures the visible viewport or full page, or whether any side effects occur.

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 tightly worded sentence: 'JPEG screenshot of the current tab.' Every word earns its place, and the key facts are front-loaded without any filler.

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 zero-parameter tool, this is nearly sufficient, but it leaves gaps that an agent must guess: the return format of the screenshot and the distinction from the sibling 'snapshot' tool. The absence of an output schema makes these gaps more significant.

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 tool has zero parameters, so there is no parameter semantics to document. The schema coverage is trivially 100%, and the description adds relevant context by specifying the JPEG output format.

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 specific action (screenshot), a specific resource (current tab), and the output format (JPEG). The tool is easy to understand, but it does not distinguish itself from the sibling tool 'snapshot', which could plausibly overlap in function.

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?

There is no guidance about when to use this tool versus alternatives like 'snapshot', 'browse', or 'extract'. The description only says what it does, not when an agent should prefer it.

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