render_image

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

With readOnlyHint=true already covering safety, the description still adds real behavioral context: modality rescale to HU, display windowing, non-square pixel correction, per-edge patient orientation reporting, and an input fingerprint. It stops short of describing failure behavior for non-DICOM or missing files, so not a 5.

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?

Three short sentences with the core action front-loaded and no filler. Each sentence contributes a distinct piece of information: what it produces, what processing it applies, and what it returns.

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?

No output schema exists, so the description carries the return-value burden and does name the PNG plus orientation and fingerprint outputs. It is nearly complete for a 6-parameter tool, though the exact shape of the orientation/fingerprint metadata is left vague.

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 every parameter including the window presets and max_size is already documented in the schema; baseline is 3. The description only loosely reinforces the windowing concept and adds nothing about frame indexing or the window_width/window_center override precedence beyond what the schema states.

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 and resource ('Render one frame of a local DICOM image as a PNG') and names the output format, which is enough to tell it apart from metadata tools. It does not explicitly differentiate from the sibling render_mpr, leaving the single-frame vs multi-planar distinction implicit.

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?

Usage is implied by 'local DICOM image' and the schema note that the path typically comes from retrieve, so an agent can infer the workflow. However, there is no explicit when-to-use statement, no mention of when to prefer render_mpr or pixel_statistics instead, and no note on preconditions such as the file needing to be DICOM.

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