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

Annotations already declare readOnlyHint, idempotentHint, non-destructive and openWorldHint=false, so safety is covered. The description adds genuine behavioral value by enumerating the response content: report summary, out-of-range values flagged High/Low with interpretation, normal findings, and clinician questions. It does not mention limits (e.g., not medical advice, or handling of unparseable text).

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?

A single front-loaded sentence with the core action first and the output contents after. The eight-item panel list is somewhat dense but earns its place by defining scope. No filler or repetition.

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, the description carries the burden of describing returns and does so thoroughly, which is the main completeness requirement for this tool. The only real gap is the unaddressed optional language parameter and any caveats about interpretation limits.

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 50%: report_text is documented in the schema and reinforced by "pasted as text" plus the panel list. The optional "language" parameter is never mentioned in the description, leaving unclear whether it controls the language of the report or of the explanation, or what the default is.

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?

"Explains a whole lab report pasted as text" gives a specific verb and resource, and the parenthetical enumerates supported panel types (CBC, LFT, KFT, lipid, thyroid, sugar, dengue, urine). The word "whole" implicitly contrasts with the sibling explain_lab_result, but the sibling is never named, so the agent must infer the boundary.

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 input constraint "pasted as text" implies when to use it (raw pasted report content rather than a structured record), but there is no explicit when-not guidance and no routing to explain_lab_result for a single value or explain_prescription for medication sheets. Usage is inferable but not stated.

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