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

Annotations already cover safety (readOnly, idempotent, non-destructive, closed-world). The description adds the meaningful data-scope disclosure that only counts and dates are returned and no wallet addresses are exposed, which tells the agent what it will and will not get back.

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, front-loaded with the core capability, followed by example intents and the output-scope constraint. Every sentence carries distinct information with no padding.

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?

No output schema and no required parameters, so the description carries little extra burden; annotations supply the safety profile. It is nearly complete, missing only a note on the default grouping, which the schema already provides.

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 coverage is 100%, so the baseline is 3. The description restates the breakdown dimensions (coin/blockchain/month/year) that the group_by enum already defines, adding little beyond what the schema documents, and omits the default of 'token'.

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 (counts) and resource (stablecoin blacklistings, freezes, seizures) with the supported breakdown axes. An agent can distinguish it at a glance from row-returning siblings like list_freeze_events.

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 three example questions ('how many wallets has Tether blacklisted', 'which coin is frozen most often', 'how many seizures happened in 2025') give concrete selection cues. However, it never names list_freeze_events as the alternative for individual events, so the routing is implied rather than explicit.

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