render_crop

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

With no annotations, the description carries the full burden of behavioral disclosure. It adds valuable details beyond the schema by stating that coordinates use PDF points (72 per inch) and that the tool returns a path and metadata, never image bytes. This clarifies the output format and coordinate system, though it omits potential side effects or permission requirements.

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 three focused sentences. The first states the purpose, the second provides coordinate units, and the third clarifies the output format. Every sentence earns its place with no redundant details.

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 tool has 7 parameters and an output schema, and the description covers the core rendering purpose, coordinate units, and output behavior. It does not mention when to use the tool or any side effects, which is a minor gap, but the existing information is adequate for a moderately complex render operation.

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 compensate. It adds meaning to the coordinate parameters (x0, y0, x1, y1) by specifying PDF points, but does not explain document_id, page, or dpi further. The parameter names are relatively self-explanatory, but the description only partially fills the gap.

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 starts with a specific verb 'Render' and identifies a precise resource: 'one PDF evidence rectangle to a local PNG artifact.' This clearly distinguishes it from sibling tools like search_evidence or get_document, which handle different 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 gives no guidance about when to use this tool versus alternatives. It does not mention prerequisites, exclusions, or when this rendering operation is preferred over other evidence-related tools. The sibling list provides context but the description itself offers no usage direction.

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