Get mention volume trends

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

The description goes well beyond the annotations by disclosing rate limits per wallet/IP, trial call limits, x402 payment-required behavior after 10 calls, retry requirements (PAYMENT-SIGNATURE or _meta['x402/payment'], Idempotency-Key), the fact that limit is ignored, and that empty windows still succeed. This is rich behavioral context that annotations alone (readOnlyHint, openWorldHint) do not provide. No contradiction with annotations.

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 front-loaded with the core purpose and pricing, then moves to usage guidance and behavioral details. Every sentence adds information, though the length is substantial. It is structured logically: purpose → pricing → usage → parameter behavior → alternatives → rate limits → payment retry. Slightly long but each sentence earns its place.

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 the tool's complexity (pricing, trial limits, payment flow, rate limits, parameter quirks) and the presence of an output schema, the description covers everything an agent needs to invoke it correctly: what it returns, what parameters do, what happens on empty windows, how to handle 402 responses, and which siblings to use instead. No critical gaps.

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. The description adds meaningful semantics beyond the schema: it explains that 'limit is ignored because aggregates stay on the full fused set', that 'platforms still filter which sources feed the series', that 'timeframe chooses lookback and bucket width', and that 'those fields never change the $0.02 USDC price'. This clarifies parameter behavior in ways the schema alone does not, earning a 4.

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: 'Return time-bucketed mention volume and sentiment with no mention rows.' It clearly distinguishes this from sibling tools by naming research_mentions and list_mentions as alternatives for different needs. The tool's purpose as a trend-over-time chart data source is explicit.

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 provides explicit when-to-use guidance: 'Use for trend-over-time charts; for a full brief with mentions use research_mentions instead; for mention-row export use list_mentions instead; to check liveness use get_health instead; to read price or trial terms use get_pricing instead.' It also explains when not to use it and names specific alternatives, which is exactly what an agent needs for tool selection.

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