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

Annotations already establish readOnly, non-destructive, closed-world behavior, so the description doesn't need to restate safety. It usefully adds behavioral detail the annotations lack: the ~380-company universe, that tier 3 is 'weekly only' (a data-granularity caveat), the (free) access note, and the exact payload fields.

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, zero filler. The core action and search keys come first, followed by the return shape, with the tier caveat parenthetically attached where it is relevant.

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 takes on responsibility for return values and does so by listing ISIN, ticker, name, tier, and date bounds. The only meaningful gap is the limit/pagination behavior, which remains undocumented in both the description and the schema.

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 only 33% (only query is documented in the schema). The description partially compensates by explaining tier semantics ('1 largest, 3 smallest, weekly only'), which the enum alone cannot convey, but it says nothing about the limit parameter or its 1-400 range and default of 25.

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 and resource ('Search the ~380 US consumer companies') with the searchable keys (name or ticker) and even enumerates the returned fields. It is unambiguous on its own, but never names or contrasts with its siblings (get_sample, get_yoy_growth, quote_sales), so the agent gets no help disambiguating this from the other lookup tools.

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?

Usage is implied rather than stated: searching by name/ticker and the note that an empty query returns the largest companies tell the agent roughly when this tool fits. There is no explicit when-to-use/when-not guidance and no mention of the alternative tools, so the agent must infer routing.

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