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

The annotations already mark it as read-only and non-destructive, and the description adds valuable behavioral context: no authentication needed, data refresh cadence (prices every minute, news every ten minutes), and the free/no-cost nature. It also clarifies what content will be included, which goes beyond the structured 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, leading with the most important facts (free, no key, no account) before listing the exact data returned. Every clause adds information about scope, freshness, or usage context, with no wasted words or repetition.

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 parameterless, read-only data-viewing tool with an output schema, the description is complete. It specifies the tickers, news sources, refresh rates, and a clear invocation scenario, leaving no ambiguity about what an agent gets or when to call it.

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?

The tool has zero parameters and 100% schema coverage, so the input schema already fully describes the invocation surface. The description appropriately explains the data payload scope instead, which is exactly what is needed for a parameterless tool. This meets the baseline for no-parameter tools without requiring additional compensation.

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 live prices for specific tickers and today's news from a parsed digest and market wire. It distinguishes itself from sibling tools by emphasizing that it is free, requires no key/account, and is meant as a first look at the swarm's data. Even without an explicit verb, the resource and scope are unambiguous.

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 explicitly says 'Call this first' and frames it as a pre-spending reconnaissance step, giving an unambiguous when-to-use instruction. It does not mention when not to use it or name alternatives, but the guidance is clear enough for an agent to decide to invoke it early.

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