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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, openWorld), and the description adds real behavior beyond them: data is delayed at least one hour, it is a free/limited sample, and each row includes realized forward price outcomes. It does not discuss rate limits or refresh cadence, but the additions are substantive.

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?

Front-loaded with the core value ('FREE sample of the premium decision') followed by the payload contents, then a one-line usage cue. Dense but every clause carries information; minor wordiness in the symbol enumeration.

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 carries the return-shape burden and does so well, enumerating the fields returned and the forward-return horizons. Missing only pagination/refresh details and explicit sibling disambiguation.

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 optional parameter at 100% schema coverage, so the baseline is 3. The description's mention of 'every symbol with live on-chain trading' plus examples reinforces the omit-to-get-all behavior, but adds no format or naming conventions beyond the schema.

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+resource: returns the latest hourly decision (action, direction, conviction, pillar scores) per symbol, delayed an hour, with 1h/4h/24h follow-through. It distinguishes itself as the 'FREE sample' versus a paid/live version, but never names the sibling decision.lite or decision.pre_trade, so sibling routing is left implicit.

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?

Gives a clear intended context: 'Judge the decisions before buying a live one,' which tells the agent this is an evaluation/preview tool rather than a live signal source. It stops short of explicit when-not conditions or naming the alternative live tool.

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