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

Annotations already declare readOnlyHint=true and destructiveHint=false, so safety is covered. The description adds valuable behavioral context: it returns a 0-100 risk score, a band, and only the single highest-severity flag (explicitly noting the full breakdown is paid). This explains a non-obvious limitation that the schema doesn't convey.

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?

Three sentences, each earning its place: purpose+signals, return values+paywall clarification, and input source. No fluff, front-loaded with the core purpose. The promotional line about the paid product is embedded naturally and also explains why only one flag is returned.

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 a single parameter with 100% schema coverage and no output schema, the description covers everything an agent needs: what it checks, what it returns, and what input to provide. It even addresses the input format explicitly, making the tool fully self-contained.

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 schema fully documents the 'videos' parameter and its nested properties. The description reinforces the field names (caption/postedAt/durationSeconds/format) and clarifies the data source (TikTok Studio's analytics export), adding marginal context beyond the schema. It doesn't introduce new parameter semantics.

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 states a specific verb ('Spot-check') and resource ('TikTok creator's exported video list') and details the exact risk signals evaluated (repetitive captions, cadence, formats, duration). It clearly distinguishes itself from sibling tools like slopcheck (YouTube) and kdpcheck (manuscripts) by naming TikTok and the Creator Rewards Program.

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 description gives clear context on when to use the tool (when you have a TikTok Studio export of a creator's own videos) and specifies the exact input format. It doesn't explicitly name alternatives or exclusions, but the niche scope makes the intended use obvious. The phrase 'Spot-check' implies a quick assessment rather than a full audit, which is useful guidance.

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