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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=true, so the safety profile is covered. The description adds that pricing is live and that no order is created, which is useful reinforcement, but says nothing about rate limits, caching, or how often prices change.

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?

Two tight sentences with the core purpose front-loaded, followed by useful scope detail. The coin enumeration is somewhat dense but earns its place as the only source of valid coin values, since the schema has no enum.

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?

With an output schema present, return values need no explanation, and all parameter provenance is in the schema. The description covers scope, supported coins, and the non-mutating nature, leaving only prerequisite ordering (search_products before this call) to inference.

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 all seven required parameters are already documented with sources (brandSlug from search_products, exact network string, etc.). The description adds the list of supported payment coins, which is mildly useful given there are no enums, but it does not add syntax or format detail 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?

States a specific verb+resource: returns the live crypto price for one product/denomination. It distinguishes itself from get_payment_methods by naming it as the source of the current coin set, but it does not differentiate from get_currencies, which an agent could plausibly confuse it with.

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 routing to get_payment_methods for the current coin set is genuine guidance, and 'Creates no order' implicitly contrasts with create_order. However, there is no explicit when-to-use condition (e.g. must call search_products first to obtain brand_slug/country_code) and no statement of when not to call it.

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