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

The description discloses cost per query, the 20-query session cap, and the dependency on a funded session, which adds meaningful behavioral context beyond the neutral annotations. It does not describe what happens if funds run out or how delivery receipts affect the response, but the commercial, state-consuming nature of the call is clear.

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?

Three short sentences convey the paid nature, price, session limit, free alternative, and required sequence with no filler. The most important constraint, per-query cost, is front-loaded before listing details, making the definition easy to scan.

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 and five parameters, the description should clarify what a successful query returns and how to form the query, but it does not. It offers good commercial and workflow context, but an agent is left guessing about query semantics, k, and receipts when invoking this paid tool.

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 low at 40%, and the description does not explain the central query parameter or the optional k and delivery_receipt parameters. The only parameter-relevant guidance is the implied origin of session_id from data_session_open; an agent still lacks semantics for the required query field and receipt-related options.

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 identifies the tool as paid per-query access to live data listings and names the specific listing, price, and session sequence. It does not explicitly say 'run the query against the funded session,' slightly blurring the execution aspect, but the tool name, title, and sequence make its role distinguishable from data_session_open and data_session_fund.

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 gives an explicit sequence — data_session_open → data_session_fund → data_session_query — and points users to data_preview for a free first taste. It does not state edge-case exclusions such as insufficient balance or when not to use the tool, but the staged flow provides clear when-to-use context.

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