Capture screenshot of the League Client

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 does add useful behavioral context: returns both an MCP image content block AND JSON metadata, and optionally saves to disk. However, it doesn't disclose failure modes (e.g., what happens if CDP isn't connected, whether targetId defaults to active page is described in the schema not description), or whether this is read-only. Moderate disclosure.

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?

Single well-structured sentence with the key mechanism and outputs front-loaded. No waste, though it could be tightened slightly.

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?

With no output schema and no annotations, the description should carry more weight. It notes the return shape (image block + JSON metadata) which is helpful, but lacks prerequisites (CDP must be active), failure behavior, and any note that this is a read/safe operation. Adequate but with clear 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 coverage is 100%, so all four parameters are documented in the schema with defaults and constraints. The description adds only the high-level notion that savePath is optional, which repeats the schema's 'Optional file path' description. Baseline 3 applies when schema does the heavy lifting.

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?

Specific verb+resource ('Capture a screenshot of the League Client window') with the mechanism named (CDP). Clearly distinguishes itself from siblings like lol_dom_query or lol_eval, which inspect state rather than produce an image.

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?

No when-to-use guidance, no alternatives named, no conditions under which a screenshot is preferred over other inspection tools like lol_eval or lol_dom_query. The agent must infer that this is for visual capture.

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