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

No annotations are provided, so the description carries the full burden, and it does substantial work: it discloses the inputs to the composite, the returned fields (score, classification, 7-day trend, historical comparison, signal summary), and an explicit per-call cost of $0.002 USDC. It does not spell out whether the call is read-only or whether the paid call can fail/retry, but the operational picture is largely there.

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 sentences, each carrying new information, with the core identity front-loaded and cost last where it belongs. Slightly dense, but no 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?

There is no output schema, so the description appropriately enumerates the return contents itself, and it adds pricing context. The main remaining gap is the absence of any guidance on how this differs from the adjacent sentiment tools.

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% and the single optional parameter includeHistory is fully documented in the schema, including its 30-day scope and default. The description adds no parameter-level detail, so 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?

States a specific resource and verb (composite Fear & Greed index) and names the exact data sources aggregated (Alternative.me plus CoinGecko signals), which pins down the semantics precisely. It stops short of differentiating itself from the sibling crypto_sentiment tool, which an agent would need to choose between.

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 explains what the tool returns but never says when to use it instead of crypto_sentiment or crypto_price, nor does it state prerequisites or exclusions. The agent is left to infer selection from name similarity alone.

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