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

With no annotations, the description carries the full burden and does substantial work: it discloses the output format (PDF), latency ('under a minute'), asynchronous behaviour (returns a job id rather than the file), quota consumption per tier, a Free-tier exclusion, and where results are persisted ('History > Planners'). It does not say what happens on generation failure or whether credits are refunded, which is the remaining gap for a credit-consuming mutation.

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?

Three dense clauses, front-loaded with the artifact and format, then eligibility/cost, then outcome and storage. Every clause carries distinct information and nothing is repeated from the schema.

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 six-parameter generation tool with no output schema and no annotations, the description supplies the critical missing pieces: cost, tier eligibility, async job-id return with the follow-up tool named, and result location. Only the meaning of the optional parameters remains unaddressed.

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 only 50%, so the description needs to compensate for undocumented parameters. It adds little: 'full-year' weakly implies the year parameter, but colour, orientation, sections and the year default/range are left entirely to the enum and type definitions with no explanation of effect on output.

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 verb ('MAKES') and a precise artifact ('full-year hyperlinked digital planner (PDF, for GoodNotes or Notability)'), which no sibling covers — make_ebook, make_spreadsheet and make_website are clearly different outputs. An agent can identify the resource and format without opening the schema.

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?

Gives concrete eligibility and cost context ('not on Free', allowance 20/40/60 by tier) and points to check_product for job status, which is genuine when-to-use guidance. It does not explicitly exclude or compare against near-neighbours such as make_ebook, but the artifacts are distinct enough that the omission is minor.

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