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

Annotations already cover the safety profile (readOnly, idempotent, openWorld), so the bar is lower. The description still adds meaningful context beyond them: the cost model ('Free', 'pay for check_figure') and the explicit non-outcome ('Returns NO verdict'), which prevents the agent from misusing the result as a judgment.

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; the pricing note is front-loaded as a one-word hook, followed by the output contract and the explicit exclusion. No sentence is wasted and the ordering prioritizes what the agent needs first.

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?

With no output schema, the description must carry the return contract, and it does: series, extracted value, date, and signals. It does not cover failure modes or input limits (4000 chars, min 4), but for a single-parameter read-only tool the picture is nearly complete.

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?

Only one parameter, and schema description coverage is 100%, so the schema already documents 'claim' fully. The description adds nothing about the claim's syntax or constraints, 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 (route) and resource (claim) plus the concrete output: target series, extracted value and date, and scoring signals. It also explicitly distinguishes itself from the sibling check_figure by declaring it returns no verdict.

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?

Explicit when-to-use vs alternative: this tool is free and returns no verdict, so the agent is told to call check_figure when a verdict is actually needed. The selection condition is stated outright rather than implied.

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