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

The annotations already cover the safety profile (readOnly, idempotent, non-destructive, closed-world), so the description only needs to add context. It adds that the text comes from the site's Armory and lists the categories of prayer available, which helps the agent predict the response. It does not discuss failure behavior when a prayer falls outside the enum, but the output schema and enum largely cover the return shape.

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?

It is three sentences with the trigger first, the content scope second, and a concrete example last. The parenthetical prayer list is long but earns its place by showing the coverage. Nothing is wasted, though the example partially duplicates the trigger sentence.

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?

This is a simple single-enum-parameter read tool with rich annotations and an output schema, so the description needs to cover only when to call it and what content it covers, and it does both. The only gap is the undisclosed relationship to the rosary mystery siblings.

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% and the enum is self-documenting, so the baseline is 3. The description goes further by grouping enum values into meaningful categories (stage prayers, rosary mysteries by day, prayers in temptation, daily examen), which helps map a natural-language request to the correct enum value. It adds no syntax guidance, but none is needed for a closed enum.

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 states a specific verb and resource: it returns the full text of a named traditional Catholic prayer. It also enumerates the content categories it covers, such as stage prayers and the daily examen. It does not distinguish itself from the sibling tools get_rosary_mysteries or list_rosary_mysteries, even though the enum includes a "rosary" value, which creates overlap.

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 trigger is explicit and front-loaded: "Call this when the user asks for the words of a traditional Catholic prayer," and the Memorare example shows how a user request maps to a call. It gives no when-not guidance, so an agent cannot tell from this description whether the rosary entry here overlaps with the dedicated rosary mystery tools.

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