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

With no annotations, the description carries the behavioral burden. It discloses that this is a read-only fetch, names the data sources, states the aggregation (median/spread), and explains the comparison output. It does not mention rate limits or error behavior, but the core behavior is transparent.

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 dense, front-loaded sentence that packs in sources, computation, output, and the reference-price use case. Every clause adds information; 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?

The description explains what data is fetched, from where, and what is reported (median, spread, deviation flag). It does not specify output format or how optional reference params behave when absent, but the schema covers parameter basics and the overall usage is clear.

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%, so the baseline is 3. The description adds a useful example ('e.g. RYO's') for the reference price and situates it in the comparison workflow, but does not substantially elaborate on reference_path or reference_fear_greed beyond schema text.

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 is explicit and specific: 'Fetch independent USD spot prices... from CoinGecko, Coinbase and Kraken', then 'report median and spread', then 'flag how far a reference price deviates'. This clearly distinguishes it from the sibling news/technical/narrative tools.

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 intended use case is clear: cross-check a reference price against independent exchange prices and surface deviation. It doesn't explicitly name alternatives or say when not to use it, but the price-comparison context is evident from the description.

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