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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description adds no behavioral context beyond that - no indication of ordering, grouping by tradition, or what a 'book' record contains - just marketing copy.

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 body opens by restating the title verbatim and then runs on as a comma-spliced fragment mixing content examples, features (plans, search), and books. Little of it is front-loaded as an actionable statement of what the call 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?

For a no-param, no-output-schema listing tool the description does convey the content scope, but it never clarifies that the return value is a list of books rather than passages or readings, leaving the distinction from lore_list_readings 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?

The tool takes zero parameters, so the schema cannot carry semantic gaps; the baseline of 4 applies. The description adds nothing parameter-related, which is acceptable here.

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 gestures at the resource ('The whole books in the Library') but never uses a clear verb like 'list', and 'Scroll the Lore' is a brand phrase rather than a stated action. It also names content (Greek/Norse myth, Theogony, Iliad, Odyssey, Poetic Edda) and adjacent features (daily readings, search, plans), which blurs the boundary with siblings lore_list_readings and lore_read_book.

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?

There is no when-to-use guidance, no prerequisites, and no named alternative among the lore_* siblings or the parallel gita_list_books / stoics_list_books tools. The agent must infer that this is the catalog-listing entry point.

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