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

Annotations already mark this read-only, idempotent, and non-destructive; the description adds useful context by detailing the per-address return fields, the rollup by operator, and the semantic caveat about misses. It also documents a non-MCP HTTP endpoint with the same behavior, though it omits explicit rate-limit or auth details.

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?

The description front-loads a full JSON-RPC invocation for a different tool and then appends an example plus an HTTP alternative. The essential verify_batch semantics are buried under extra instruction text, making the definition longer and harder to scan than necessary.

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?

With no output schema, the description supplies the key missing output details: matching prefix, publishing source, mirror time, and operator rollup. It also covers batch limits, input shape, and result interpretation, so an agent has enough to invoke and interpret the tool correctly despite the noisy preamble.

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 schema already covers the single 'addresses' parameter at 100%, so the baseline is 3. The description adds meaning by explaining the role of the 'claim' field and showing a concrete hit/miss example that goes beyond the schema's type-level 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?

The core operation is clearly stated: 'Check up to 500 addresses against every mirrored operator prefix list in one call.' The verb, resource, and batch scope are specific, though the description never explicitly differentiates it from siblings like verify_my_address or lookup_prefix.

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?

It provides concrete invocation context: batch use, maximum 500 addresses, accepted input formats, and an explicit example with ip/claim pairs. It also cautions that a miss is not evidence of a fake, which helps agents interpret results. The leading 'FIRST CALL' reference to another tool is confusing, but it does not make the main usage conditions unclear.

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