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

Annotations already declare read-only, open-world, and idempotent behavior. The description adds useful operational context: Base chain, per-call pricing, prepaid header option, free call/day, and no wallet/API key requirement. This goes beyond annotations without contradicting them.

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 core behavior is front-loaded and the access/pricing details are useful. Minor redundancy appears in repeating 'across 1h / 6h / 24h' and 'across 1h, 6h and 24h windows,' but the overall length is justified.

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 simple read-only tool with an output schema, the description covers chain, required input, windows, trend read, pricing, and access requirements. Nothing necessary for correct invocation is missing.

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 already covers the only parameter with 100% coverage, so the deescription doesn't need to explain address syntax. It adds one useful semantic: the token is on Base. Beyond that it mostly restates 'Required input: address,' which is already in 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?

States a specific resource (Base token price/volume) across multiple time windows plus a trend read, which clearly distinguishes momentum from a single 24h number. The purpose is concrete and actionable.

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?

Explains it is for gauging momentum and explicitly notes it is not a single 24h number, which implies use for multi-window trend assessment rather than spot price. It does not name a specific sibling tool or exclusion case, but gives enough context to route correctly.

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