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

Annotations already declare readOnlyHint=true, idempotentHint=true, openWorldHint=true and destructiveHint=false, so the safety profile is fully covered by structured data. The description adds only that the tool reports the current value and classification, which is useful but does not disclose freshness, update cadence, or how the classification is derived.

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?

A single short sentence with no filler and the resource name front-loaded. It reads as a noun phrase without a verb, which is mildly telegraphic but efficient.

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 no output schema, the description carries the burden of describing the return, and it does so at a high level ('current value and classification'). It would be stronger if it specified the 0-100 scale or the classification labels, but it is adequate for a no-argument read tool.

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?

The tool takes zero parameters, so the baseline is 4. There is no argument syntax for the description to clarify and nothing is left ambiguous about the call signature.

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?

Names a specific resource (Crypto Fear and Greed index) and states exactly what is returned: the current value and its classification. It is clearly distinguishable from siblings like get_price or get_funding, though it does not explicitly contrast itself with any of them.

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 gives no when-to-use context, no mention of what the index is useful for (e.g. sentiment gauging), and names no alternatives. For a zero-parameter single-purpose tool the cost is low, but no guidance is actually present.

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