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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=true, but the description adds substantive context beyond them: that the call is free and 'generates nothing', that results include per-account availability with unlock {plan, name, url} ordered Pro first, and that no size is preselected. That account-level locking/unlock behavior is not derivable from the annotations and is exactly the kind of trait worth disclosing.

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?

Nearly every clause carries information that substitutes for the absent output schema, so length is defensible. The problem is structure: two long run-on sentences with fragments ('The show types and season sizes, for when the season size is asked') bury the actionable rule about not defaulting a size in the middle of a return-value catalog rather than front-loading it.

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 no output schema, the description takes on the burden of describing returns and does so thoroughly: show types with format and writing guidance, season sizes across episodes, durations and resolutions, the seedance-2.5 engine, pricing, and per-account lock state with unlock links. What remains thin is the input side, where show_type's role in filtering is left implicit for a two-parameter tool.

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 description coverage is 0%, so the description has to carry parameter meaning. It does explain series_id ('the planned series id (a micro drama already bound to a show)') and effectively enumerates show_type's values (drama_romance, comedy_sitcom, thriller_horror, fantasy_scifi), which partially compensates. However show_type is never explicitly framed as the input that narrows the result set, leaving the caller to infer how the two optional params interact.

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 names the specific resource returned (the four show types and every season size with price and availability) and distinguishes the tool from its sibling: 'A new series starts with series_interview, not here.' It is not a tautology, but the opening fragment 'The show types and season sizes, for when the season size is asked' is grammatically loose enough that an agent must read further to be sure it is a read-only catalog lookup rather than a plan generator.

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?

It gives real triggering conditions: 'after Episode 1 is delivered, or when the customer chose the whole season now', and an explicit exclusion via series_interview. It also states a behavioral rule for the no-default case: 'When the size is asked it has no default: post say and let the customer pick one.' It stops short of naming an explicit alternative for plan authoring (e.g. get_season_plan), so it is clear but not fully routed.

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