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

Annotations already declare readOnlyHint=true, and the description builds on that by detailing the exact data scope (probe outcomes, price/payout changes, on-chain history) and the per-call price. It does not mention pagination or output limits beyond the schema's days parameter, but the disclosed scope is substantial for a read-only history endpoint.

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 compact and well-structured: a rich first sentence defines the output, a second sentence gives usage context, and a third provides pricing. Every sentence earns its place without redundancy or 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?

For a read-only historical query with two well-documented parameters and a clear data-scope statement, the description gives an agent enough to invoke it correctly. It could be slightly more complete by describing the response shape or pagination, but since there is no output schema, the named evidence categories provide reasonable guidance.

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 description coverage is 100%, with both 'resource' and 'days' already explained in the input schema. The tool description adds general context about time-series evidence but does not add new parameter-level meaning beyond what the schema provides, so the baseline score of 3 is appropriate.

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 clearly states what the tool does: it returns 'the full time series behind a score' with specific evidence categories (probe outcomes, price/payout-address changes, on-chain settlement history). This is more specific than the generic title and distinguishes it from the sibling tools by framing itself as 'the evidence itself rather than the summary.'

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: 'Call this when a verdict surprises you, or before committing to a service you plan to depend on.' It contrasts the tool with a summary-style result, but it does not name a specific sibling alternative or state when not to use it, so it falls just short of full alternative routing.

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