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

The description reveals that the tool is a paid, per-query operation on a specific listing, with a hard cap of 20 queries per session and a price of 0.01 USDC per query — useful behavioral constraints beyond the annotations, which are all false and uninformative. However, it doesn't disclose side effects such as consuming session balance, receipt behavior, or failure modes. The annotations do not contradict the description.

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 compact, front-loads the pay-per-query concept, and packs useful constraints (price, cap, sequence) into three short sentences without fluff. The listing detail is relevant because it tells the agent what data product is being purchased.

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?

The tool has 5 parameters and no output schema, yet the description never explains how to form a query, what k or delivery_receipt mean, or what the response looks like. It does provide the essential funding flow and pricing/limit context, but an agent cannot correctly use advanced parameters or anticipate return values from this definition.

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?

With only 40% of parameters described in the schema (session_id and sandbox_receipt), the description should compensate by explaining query, k, and delivery_receipt. It provides none of that; the only parameter-relevant hints are 'per-query' and the session sequence, which implicitly point to query and session_id. This is insufficient for a 5-parameter tool.

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 frames the tool as 'Buy per-query access to live data listings' and names a specific listing with price and session cap, so an agent can tell this is the paid query step rather than the free preview. The verb is commercial ('buy') rather than explicitly 'run a query', but the sequence ending in data_session_query and the annotations title 'Query Data Session' make the operation unambiguous. It also distinguishes the tool from data_preview as the free alternative.

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 a prerequisite sequence (data_session_open → data_session_fund → data_session_query) and explicitly points to data_preview for a free first taste, so an agent knows when to use this tool and which sibling to try first. It does not spell out exclusions such as 'do not use before funding', but the funded-session context is clearly implied.

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