page_crop

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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive), and the description adds real behavioral value: it returns an inline PNG plus metadata and re-renders from source rather than upscaling a thumbnail. Return format is disclosed despite the absent output schema.

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?

Front-loaded with the core action and return type, then dense factual detail with no filler. Every sentence (coordinate system, example, dpi range, search-hit guidance) earns its place.

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 a read-only tool with no output schema, the description covers return type, coordinate semantics, dpi bounds, and a use case, which is sufficient to invoke it correctly. Minor gaps around file/page expectations remain but are low risk.

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 0%, so the description must carry the load, and it does for the ambiguous parameters: bbox is defined as [x0,y0,x1,y1] normalized 0..1 with top-left origin of the full page, plus a concrete example, and dpi is bounded to 36..600. Only file and page are left implicit, which are largely self-evident.

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?

States a specific verb (re-render), resource (PDF region), and output (inline PNG and metadata). This clearly distinguishes it from the sibling page_render, which renders a full page, while page_crop targets a region.

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?

Tells the agent when this applies: 'Expand search hit bbox to include surrounding wires/components,' linking it to a search workflow. The note 'Not an upscale of a thumbnail' clarifies it re-renders from source, but no sibling is explicitly named as the alternative.

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