get_screen_images

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

No annotations are provided, so the description carries the full burden. It states the tool returns images and a JSON index, implying a read-only operation with no side effects. However, it does not disclose any rate limits, size constraints, authentication requirements, or format details of the images, leaving some ambiguity for an AI agent.

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 consists of two concise sentences. The first immediately states the primary function, and the second provides a workflow tip. No superfluous information is included, and the most critical details are front-loaded.

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 description explains the return value (images and JSON index) and its role in a larger workflow. However, it omits details about the index structure, whether screenIndices is optional (though inferred from the schema), and the significance of locale. Considering the tool's simplicity and lack of output schema, the description is mostly complete but leaves minor gaps.

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 low (33%), with only the screenIndices parameter having a brief description. The tool description adds meaning about the output (images and index) but does not explain the purpose or constraints of the projectId or locale parameters. As a result, the description fails to compensate for the underdocumented schema.

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 clearly states the tool returns raw app screenshot images and a JSON index mapping images to screen indices. It uses a specific verb ('return'), identifies the resource ('raw app screenshot images'), and hints at its role in a workflow with 'update_screen_text', distinguishing it from sibling tools that involve push or listing operations.

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 explicitly directs to use this tool with client vision to read UI content before calling update_screen_text, providing clear context for when to use it. It does not, however, mention when not to use it or alternatives, but given the sibling list includes only update_screen_text as a closely related tool, this is sufficient.

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