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

Annotations mark read-only and idempotent, but the description goes further: it discloses that counts only are returned (no identities), that it is always free on the match meter, and that the rate window weighs exactly like a real resolve. It also explains the 'band' semantics, adding valuable behavioral context beyond annotations.

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?

Description is fairly long but every sentence contributes meaning: cost, rate window, constraints, band interpretation, cross-chain caveat. The prose is tightly packed and organized in digestible paragraphs; the only minor issue is that some phrasing ('the band a resolve would bill inside') is dense enough to require rereading.

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 a single simple parameter and no output schema, the description fully compensates: it explains what counts are returned, how to interpret the high/low band, the cost model, and the minimum/ceiling constraints. An agent can select and invoke this tool correctly with no further reference.

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 only parameter, addresses, is fully described in the schema (format, min/max). The description adds nuance by specifying 'distinct addresses' and tying minimum count to aggregate-by-design behavior, giving practical validation guidance beyond the schema.

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?

Description begins with 'A dry run over a list of addresses' followed by explicit output counts, clearly distinguishing it from spending/consuming operations. It names the decision purpose 'decide whether a list is worth resolving, and which tool to spend on', making the tool's unique role unmistakable.

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?

Explicitly states when to use ('Use it to decide whether a list is worth resolving') and points to alternatives: the coverage tool and /v1/stats for per-chain match rates. Also lists constraints (minimum 10 addresses, batch ceiling) and cost behavior, leaving no ambiguity about appropriate invocation.

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