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

Annotations already declare a safe read (readOnlyHint=true, destructiveHint=false, openWorldHint=false), so the bar is lower. The description nonetheless adds real behavioral context: exports are free, video and cover may come back still rendering, and callers must poll using retryAfterMs until status is 'ready (url)' or 'unavailable'.

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 capability statement is front-loaded and every sentence carries information (format meanings, polling behavior). It runs long across multiple clauses, but there is little filler and no repetition of 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?

With an output schema present, return values need not be explained, yet the description still conveys the async rendering contract (retryAfterMs, ready/unavailable). Combined with cost, input preconditions, and format semantics, an agent has everything needed to call and handle results 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 well beyond the schema's bare enum list by defining each value: no_music = voice+captions without music, clean = voice+music without burned-in captions, srt/vtt = subtitle file as text, cover = opening frame still. This meaningfully disambiguates the single most consequential parameter choice.

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 first sentence states a specific verb and resource: 'Get a posting export of a finished Topic Short,' immediately distinguishing this from generate_topic_short (creation) and get_topic_short (metadata). The 'finished Topic Short' scope plus the format enumeration makes the tool's output unambiguous 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?

'Finished Topic Short' and 'at no cost' imply when the tool is applicable, and the per-format notes hint at intent (e.g., use no_music if you want to 'add a trending sound in the app'). However, there is no explicit when-to-use/when-not guidance, no statement of prerequisites beyond 'finished,' and no routing to a sibling.

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