get_screenshot_dir

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

No annotations are provided, so the description carries full burden. However, it contradicts the input schema: the description marks 'caller_agent_id' as required ('必須'), while the schema lists it as optional (default null) and not in required array. This inconsistency misleads the agent about invocation 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?

The description is brief and structured with clear 'Args' and 'Returns' sections. However, the inclusion of both Japanese and English is slightly redundant, and the required field mismatch wastes space.

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?

Given the tool has one optional parameter and an output schema (implied by 'Returns'), the description covers basic return fields. However, it lacks edge case behavior (e.g., what happens if directory doesn't exist) and usage context. Adequate but not thorough.

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 description adds meaning to the sole parameter by labeling it as 'caller_agent_id' (caller agent ID) but misstates its required status. Schema coverage is 0%, so description must compensate; it partially does but the error reduces clarity.

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 it retrieves the screenshot directory ('スクリーンショットディレクトリを取得する'), which is a specific verb-resource combination. Among sibling tools like list_screenshots, read_screenshot, and read_latest_screenshot, this tool uniquely provides the directory path, distinguishing its purpose well.

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 provides no guidance on when to use this tool versus alternatives, no prerequisites, and no exclusions. It simply states what the tool does without contextualizing its usage in the broader workflow.

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