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

No annotations are present, so the description carries the full burden. It adds meaningful behavioral context: 60-second caching and a $0.001 cost per call, while implying a read-only price lookup. It does not disclose failure modes, unsupported-symbol behavior, or rate limits, but for a simple quote tool the disclosed caching and pricing traits are useful. There is no contradiction with annotations.

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 a single front-loaded sentence with no filler, and the cache and cost details justify their inclusion. It is appropriately sized for a simple price tool. The vague 'etc.' and lack of any structural separation keep it from a perfect score.

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-parameter price lookup with an output schema, the description covers the core resource, caching, and cost. Missing usage guidance and an unexplained optional parameter create clear gaps, but an agent could probably make a successful call using the provided symbol examples. Since an output schema exists, detailed return-value documentation is not necessary.

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 0%, and the description does not explicitly map to the schema's parameters. It does provide concrete symbol examples, which helps the agent understand what 'symbols' likely accepts, but it leaves the optional agent_id parameter completely unexplained and does not clarify the string-or-array flexibility. The cache/cost note is behavioral, not semantic, so parameter meaning remains mostly under-specified.

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 identifies the resource ('USD prices') and the scope of symbols ('eth/usdc/usdt/wbtc/aero/degen etc.'). It lacks an explicit verb like 'gets' or 'returns,' but 'USD prices for' strongly implies retrieval and the tool name reinforces it. It is broadly distinguishable from crypto siblings like portfolio or token metadata, though it does not call out any specific 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?

There is no guidance about when to use this tool versus related tools such as ddg_crypto_portfolio, ddg_token_estimate, or ddg_eth_gas. No contexts, exclusions, prerequisites, or alternatives are mentioned. An agent must infer usage entirely from the tool name and the short description.

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