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

Annotations already mark it read-only, open-world, non-destructive, and non-idempotent, and the description adds substantial behavior beyond that: live tool selection, structured output fields, sample-without-payment behavior, and the x402 USDC settlement cost of $0.25 per call.

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 front-loaded with the core purpose and alternative routing, and every sentence carries useful information. It is somewhat dense because it also covers payment, samples, and output structure, but there is no obvious filler.

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 paid, open-world analysis tool with an output schema and rich annotations, the description is complete: it explains what is returned, how payment works, that a free sample is available, and which sibling to use for a fixed report.

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 100%, so the required question, optional context, and language enum are already documented. The description reinforces the question parameter with examples but does not add meaning for context or language beyond what the schema provides, so the baseline 3 applies.

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 verb and resource: it answers a user-provided crypto market question rather than a fixed report. It explicitly distinguishes itself from get_market_brief, which is described as the fixed one-coin report 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?

It gives concrete example questions and names the condition for choosing the sibling: use get_market_brief instead for a fixed report on one coin. It also explains the no-payment sample path, which helps an agent decide when calling is appropriate.

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