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

With no annotations provided, the description carries full burden. It discloses a 10-minute cache, directs users to check 'meta.cacheAgeSeconds' for freshness, and explains meta fields. This adds useful behavioral context beyond basic operation.

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?

Every sentence adds distinct value: front-loaded with primary action, then sibling differentiation, then technical details (cache, meta fields). No wasted words.

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?

Given no output schema, the description partially compensates by mentioning meta fields and explorer references. However, it could more explicitly describe the structure of each whale transfer entry (e.g., fields like amount, token, chain, explorer link). Still, it's mostly complete for a simple 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?

There are no parameters, so baseline is 4. Description adds no parameter-specific info, but schema coverage is 100% vacuously.

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 states the tool retrieves the latest 3 whale transfers as a live snapshot across 14 chains. It distinguishes itself from siblings 'whale_activity' and 'whale_movements' by specifying their different purposes (counts vs. paginated archive).

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 explicitly advises when to use alternative tools: 'use whale_activity for counts, whale_movements for paginated archive', providing clear usage context and exclusions.

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