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

Annotations already declare readOnlyHint, idempotentHint, and non-destructive, so safety is covered. The description adds no further behavioral detail—no mention of return format, pagination, rate limits, or authentication. It's adequate but doesn't go beyond the annotations in any meaningful way.

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 a single, efficient sentence that front-loads the purpose and includes helpful examples. No wasted words, and it reads naturally.

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 array parameter), and annotations cover safety. However, the description lacks the precise format for 'refs' and doesn't explain what the output will look like (though no output schema is given). For a simple recommendation tool, this is moderately complete but leaves a key detail ambiguous.

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% for the sole parameter 'refs', so the description must compensate. It hints that refs are passage references ('one or more passages', 'set of verses') but doesn't specify the expected format (e.g., 'Genesis 1:1' or Sefaria reference conventions). This is a significant gap for correct invocation.

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 recommends topics relevant to passages, with a specific verb and resource. It gives concrete examples (tagging source sheets, finding themes) that help an agent understand the purpose. It doesn't explicitly differentiate from siblings like search_topics or get_topic, but the unique angle (topics for passages) is clear enough.

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 implies use cases through examples ('for tagging a source sheet or finding themes in a set of verses') but doesn't explicitly state when to prefer this over alternatives like search_topics or get_topic. There's no explicit exclusion or comparison to siblings, so an agent must infer the appropriate context.

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