read_asset_prices

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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint, so the safety profile is covered structurally. The description adds the useful detail that multiple addresses can be batched in one call and that results are keyed by address, but says nothing about behavior on unknown/unsupported addresses, cross-chain price differences, or rate limits — meaningful for an openWorld tool.

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?

Three short sentences, front-loaded with the core purpose and with zero filler. The third sentence about the return shape is slightly redundant given an output schema exists, but it does not bloat the definition.

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 two-param read with rich annotations and a declared output schema, the essentials are present, but the description never mentions that prices are chain-scoped or that chain_id defaults to Base — a real omission given the tool prices assets across four chains. Edge-case behavior (unpriced assets) is also unaddressed.

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 coverage is 100% and both parameters are documented there, including the enumerated chain IDs, so the description is not required to compensate. It restates the comma-separated address format (already in the schema) but adds nothing to clarify chain_id's default of 8453 or its effect on pricing.

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 and resource — 'Get USD prices' for 'asset addresses' — which is concrete and clearly separable from siblings like read_asset_list (enumeration) or read_wallet_balances (holdings). It stops short of naming or contrasting those siblings explicitly, so an agent must infer the boundary itself.

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 implies the usage context (batch price lookup) and explains how to supply multiple addresses, but gives no when-to-use/when-not guidance, no pointer to read_asset_list for discovering addresses, and no mention of when chain_id matters.

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