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

Annotations already declare this a safe, idempotent read (readOnlyHint, idempotentHint, destructiveHint=false), so the safety profile is covered. The description adds a genuinely non-obvious behavioral trait: the result is empty until a separate generation step has run, which prevents the agent from misreading an empty response as an error.

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, both front-loaded and information-dense: the first defines scope and payload, the second the dependency. No filler.

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?

No output schema exists, yet the description compensates by enumerating the returned fields per platform. Combined with the prerequisite note and full parameter documentation, an agent has everything needed to call and interpret this 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 coverage is 100% and the single snapshot_id parameter is fully documented in the schema (including its provenance, 'from get_trends'). The description's phrase 'for one trend snapshot' reinforces but does not extend that meaning, so the baseline 3 applies.

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 (Get) and resource (per-platform content for one trend snapshot), then enumerates the actual payload: hashtags, YouTube title/description, Medium title/subtitle. It is clearly distinguishable from the sibling generate_trend_platform_content, which produces rather than retrieves this content.

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?

Names the sibling generate_trend_platform_content and states the condition under which output exists ('Empty until ... has run for it'), which routes the agent to the generator first. It does not, however, contrast against use_trend_platform_content or state when-not-to-use explicitly.

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