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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the description doesn't need to repeat safety. It adds cost information (0.2 HBAR) and specifies the data categories returned, which are beyond the annotations. No contradiction found.

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 is a single concise line, front-loading the tool's purpose, key data types, and the critical exclusion of execution. Every phrase adds value—the cost and state aspects are all relevant. 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?

For a two-parameter read-only tool with complete schema and clear annotations, the description provides enough context: purpose, what data is returned, cost, and a key usage exclusion. It doesn't detail return structure, but given no output schema, the description's coverage is adequate.

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 input schema covers both parameters with thorough descriptions (contract_id and api_key). The description doesn't add parameter syntax details, but with 100% schema coverage, the baseline of 3 is appropriate. The description's mention of 'state' plus the schema is sufficient.

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 reads Hedera contract state, listing specific aspects (info, bytecode size, recent activity, storage). It explicitly says 'No tx executed', distinguishing it from contract_call and other executory tools. This is a specific verb-like resource scope with sibling differentiation.

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 statement 'No tx executed' provides a clear exclusion, implying this tool is for read-only state inspection and not for executing transactions on the contract. While it doesn't explicitly name contract_call as the alternative, the contrast is clear and sufficient for an agent to choose correctly.

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