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

Annotations already declare readOnly, idempotent, and non-destructive behavior. The description adds meaningful behavioral context by disclosing that the tool accepts three different paragraph reference formats (globalId, standardReferenceId, paperSectionParagraphId), which is useful for correct invocation and not captured by the annotations.

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 exceptionally concise: two sentences with no extraneous information. The first sentence states the core purpose, and the second clarifies input formats. Every word 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?

The tool is simple (one parameter, read-only, output schema present). The description covers the essential behavior and input flexibility. With annotations and an output schema, nothing critical is missing for a getter of this nature.

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?

Although the schema covers the parameter with a description and example, the description goes significantly beyond by providing concrete examples of all three accepted reference formats. This adds valuable meaning and reduces ambiguity for the agent, exceeding the baseline for high schema coverage.

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 clearly states the tool's function: 'Get the audio file URL for a specific paragraph.' It uses a specific verb and resource, and the mention of multiple reference formats distinguishes it from sibling tools like paragraphs.get or bible.verse, which focus on text/content.

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 clear context: use this to retrieve audio for a specific paragraph, and it emphasizes that any paragraph reference format is accepted. However, it does not explicitly mention when not to use it or name alternatives, stopping short of the highest score.

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