List a season's coverage or an episode's subtitles

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

The annotations already mark the tool read-only and idempotent; the description adds useful behavioral detail beyond that: the kind field reports coverage versus subtitles, the season default behavior, and the fact that each record carries the page to open to download it. It also notes in the schema that unknown ids return a page.

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 description is dense but every sentence earns its place: purpose, id source, mode semantics, default behavior, and result interpretation are all covered without fluff. The main behavioral details are front-loaded.

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?

Given an output schema exists and all parameters are documented, the description covers the necessary call-shaping details: how to switch modes, default season behavior, and what the records contain. Nothing critical is missing for an agent to invoke this correctly.

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 100%, so the baseline is 3, but the description goes further by explaining the relationship between season and episode, how the output changes depending on their combination, and what omitting season does. This adds real meaning beyond the individual parameter descriptions.

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 opens with a specific verb and resource: 'List what tvsubtitles.net holds for one series.' It then distinguishes its two modes, season coverage versus episode subtitles, and clearly separates it from siblings like get_subtitle and search_titles by explaining the object being listed.

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 explicit usage context: pass id from search_titles, use season alone for coverage, add episode for subtitle records, and omit season to get the newest season. It does not explicitly exclude alternatives like get_subtitle, but the mode-based guidance is clear and actionable.

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