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

Annotations already declare a safe read-only, idempotent, non-destructive, non-open-world operation, so the description only needs to add context. It adds two useful facts beyond that: the call is free (billing implication) and it is a strict subset/alias of GET /preview, plus the phrase 'one excerpt' discloses that the content is deliberately truncated rather than complete. It omits rate limits or size limits, keeping it below a 5.

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?

A single sentence with the most decision-relevant token ('Free.') front-loaded, followed by the payload inventory. The telegraphic style ('Free.' as a fragment, semicolon-free comma list) is slightly clipped but every clause carries information.

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?

With zero parameters, no output schema, and a full safety annotation set, the description's only remaining job is to characterize the return value, which it does field by field. An agent knows what it will get and that it costs nothing; only the truncation/limits policy is left vague.

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 no parameters, so there is nothing for the description to disambiguate; baseline 4 applies. The description correctly makes no parameter claims rather than inventing any.

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 enumerates exactly what the tool returns (title, description, table of contents, section list with prices, one excerpt, terms summary), which is more informative than a bare verb+resource. It implicitly distinguishes itself from the sibling get_table_of_contents by noting that the TOC is only one component of a larger payload, though it never names that sibling.

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?

'Free.' signals a cost-free alternative and the content list implies when this is sufficient versus needing fuller data, but there is no explicit when-to-use, when-not-to-use, or named alternative among get_checksum, get_master_checklist, and get_table_of_contents. Usage has to be inferred.

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