cmc_fear_greed_historical

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

No annotations are provided, so the description carries the full burden. It does disclose useful behavior beyond the schema: results are paginated and drawn from the provider's daily series, which tells the agent about granularity and page-wise delivery. It says nothing about rate limits, ordering of results, or what happens at the pagination boundary.

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 front-loaded sentence with no filler; the core purpose and the pagination/source qualifier are packed efficiently. Nothing to trim, though it is short enough that it leaves gaps rather than being wasteful.

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?

An output schema exists, so return values need not be explained. However, for a paginated data tool with 0% param coverage and no annotations, the description omits how pagination actually works, leaving the agent to guess at limit/start semantics.

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%, so the description must explain 'limit' and 'start', but it only says 'paginated' without defining what limit caps (default 50, max 500) or what start indexes. The two optional integer parameters remain semantically undocumented in both the schema and the description.

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 ('Get') and resource ('historical CoinMarketCap Crypto Fear and Greed values'), and the word 'historical' implicitly distinguishes it from the cmc_fear_greed_latest sibling. It stops short of naming the sibling or the date granularity explicitly, but an agent can identify what the tool returns.

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?

Usage is only implied by the word 'historical' – the agent can infer this is for past data rather than the current reading, but the description never says when to prefer cmc_fear_greed_latest versus this tool, nor any prerequisites. Adequate but with a clear routing gap.

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