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

The description explains what the tool returns (funding instructions and createEscrow calldata) and its access restrictions. It does not contradict the readOnlyHint and idempotentHint annotations, as it only returns instructions rather than executing transactions.

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 moderately concise, containing essential information in a few sentences. Some phrasing like 'first taste free' is slightly informal, but it does not detract from clarity and keeps the description within reasonable length.

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 description covers the tool's purpose, authentication, endpoint, and output. It does not detail response schemas, but given the lack of an output schema and the simple GET nature, the information is sufficient 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?

The single required parameter session_id is clearly described as a UUID from data_session_open, and the description additionally mentions 'opened data session' in prose. The schema coverage is 100%, so the description adds useful context without redundancy.

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 the tool's purpose: buying per-query access to live data listings and returning funding instructions and createEscrow calldata for an opened data session. It also specifies the REST endpoint, making the function 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 provides practical usage guidance by noting the required agent API key (Bearer or X-API-Key), stating that the tool is not guest-callable, and mentioning the 'first taste free via data_preview' option. It does not explicitly compare with sibling tools, but the context is sufficient for most agents.

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