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

Annotations already declare read-only/idempotent/non-destructive, but the description goes well beyond them: the exact read procedure (code, EIP-1967/1822/OZ legacy slots, slot 0, one multicall), the staleness caveat that an upgradeable proxy's implementation can change after the read, the 5xx-and-not-charged behavior on malformed node answers, typical latency (1-4 s), price (USD 0.002) and a free tier (10 reads per IP per UTC day).

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?

Front-loaded with the purpose and the sibling exclusion, then a compact chain of procedural detail, caveats, and pricing. Dense but every sentence earns its place; the long `kind` enumeration is the only borderline element and it materially aids interpretation.

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?

Despite an output schema existing, the description covers everything an agent needs to call this correctly and interpret it: classification kinds, return fields, staleness caveat, failure semantics, cost, rate limits, and a docs link. Nothing material is missing.

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% and the schema documents both `chain` (with enum) and `address` (with pattern/length), so the schema already carries the parameter burden. The description adds no parameter-level detail (no enum values restated, no address format guidance), so the baseline 3 applies.

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+resource ('detect whether a contract is a proxy, and of which kind') and immediately distinguishes itself from the closest sibling: 'For code size and hash use get_contract_code.' An agent can pick it out of the very large sibling list without opening a schema.

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 explicitly routes the code-size/hash use case to get_contract_code and describes the trigger context (you want proxy classification and implementation/admin/beacon). It does not, however, address when this is preferable to siblings like scan_contract_source, check_contract_before_interaction, or get_storage_at, so the guidance is clear but not exhaustive.

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