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

Annotations already cover the safety profile (readOnlyHint, openWorldHint), so the bar is lower. The description adds genuinely useful behavior the annotations don't: what each hit contains (still, tags, deep link to the exact moment) and an explicit cost delta (8 credits with clips vs 2 without), which matters for a paid, open-world search.

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?

Two sentences, front-loaded with the purpose and examples before the output description. The long parenthetical tag list is dense but each item corresponds to a real filter param, so it earns its space; the only mild redundancy is restating what a shot result contains.

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 29-param open-world search with no output schema, the description explains the return shape (still, tags, exact-moment link, optional clip) and cost, which is the critical missing piece. It stops short of saying whether query and filters combine as AND, how results are ranked, or the default limit.

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 69%, so the schema does much of the work, but the description adds meaning beyond it: the query should read as a description of one frame, the tag taxonomy (size, angle, setting, time of day, lighting, mood, people, product/logo) maps the filter params into groups, and clips carries its cost tradeoff.

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?

Opens with a specific verb and resource ('Find individual SHOTS inside commercials') and immediately scopes it to frame content with three concrete query examples. It also makes clear the result unit is a shot, not a commercial, which separates it from search_commercials even though the call accepts commercial-level filters.

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?

The frame-description framing implies when to reach for it, and it gives one real usage rule ('Ask [for clips] only when the user wants to see the shots move'). But it never names an alternative or an exclusion, despite siblings like search_frames, similar_commercial_shots and search_commercials that an agent must choose between.

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