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

Annotations already declare this is a non-read-only, non-idempotent, non-destructive operation. The description adds important behavioral context beyond that: prepaid per-query cost, a maximum of 20 queries per session, and the prerequisite session funding flow. It still omits receipt handling and failure/charge behavior, so it is not fully complete.

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 three tightly structured sentences: what it does, listing-specific pricing/cap details, then the required sequence. It is front-loaded and every sentence carries actionable information.

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 payment-adjacent query tool with no output schema, the description covers cost, session cap, and the prerequisite flow. However, it does not explain the response shape, the meaning of `k` or receipt parameters, or charging behavior on failure, leaving notable gaps for correct invocation.

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 40%, so the description must compensate for five parameters. It does not explain `query`, `k`, `delivery_receipt`, or `sandbox_receipt`, and only indirectly implies `session_id` through the required session sequence. The description adds little parameter-level meaning 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?

The description states a specific action and resource: per-query access to live data listings, with the exact listing (samsungwatch), price (0.01 USDC), and session cap (20 queries/session). It also distinguishes the paid query from the free `data_preview` sibling.

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?

It gives clear usage context by naming the free alternative `data_preview` and the required session sequence `data_session_open → data_session_fund → data_session_query`. It does not explicitly state when not to use the tool beyond the preview alternative, so it falls just short of a full 5.

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