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

Annotations already mark the tool read-only and idempotent; the description adds valuable behavior beyond that: silent omission into a `missing` array instead of failing the batch, the 50-id cap, and default shortcode expansion with a raw escape hatch. These details materially affect how an agent interprets results.

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?

Four dense sentences cover operation+cap, use case, return shape, and failure semantics with no filler. The most decision-relevant facts are front-loaded, and every sentence 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?

Together with the rich schema and output schema, the description gives the agent everything needed to invoke the tool correctly: batch limits, per-page output shape, shortcode behavior, and the distinction between returned pages and missing ids. Nothing relevant is left unexplained.

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 input schema already documents both parameters in detail: Mongo `_id` list, 50-id cap, silent missing behavior, and the raw toggle. The description adds the return-shape relationship to imagine_get_adventure_page, but that is contextual framing rather than new parameter-level semantics. With 100% schema coverage, baseline 3 is appropriate.

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?

States a specific operation and resource: 'Batch read of adventure pages by id.' The 50-per-call cap and the reference to imagine_get_adventure_page clearly distinguish this from the single-page sibling, so an agent can identify it at a glance.

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?

Explicitly recommends this tool when walking an act and reading several scenes' bodies, framing it as one call instead of one tool invocation per page. It doesn't explicitly spell out the reverse case ('use imagine_get_adventure_page for a single page'), but the use context and sibling relationship are clear enough.

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