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

Annotations already declare readOnlyHint=true and destructiveHint=false, establishing a safe read operation. The description adds value by detailing the response structure (0-100 score, A-F grade, component breakdown) and noting it is free, which goes beyond annotation coverage. No contradictions with 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?

The description is two sentences with no filler. The first sentence states the action and scope, and the second efficiently communicates the output, cost, and accepted input formats. Every clause earns its place.

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 simple read-only query tool with two parameters, the description covers the purpose, input requirements, and output structure. It could also mention edge cases like behavior for unregistered agents or invalid DIDs, but the provided context is sufficient for the tool's complexity.

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%, with both parameters (api_key and did_or_account_id) well-described in the schema itself. The description reiterates that you can pass a Hedera account ID or full did:hedera DID, but this adds no new meaning beyond what the schema already provides, so a baseline 3 is appropriate.

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 uses 'Query' as a specific verb and clearly identifies the resource as a live Fixatum KYA trust score for any registered agent. It also lists the return values (score, grade, component breakdown), making the purpose unambiguous. It doesn't explicitly differentiate from sibling tools like fixatum_status, but the resource name is distinctive enough.

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 description implies when to use this tool: when you need a live KYA trust score for a Hedera agent. It mentions 'for any registered agent' and includes 'Free' as a practical consideration. However, it provides no explicit when-not-to-use guidance or alternatives among the sibling tools, leaving usage context implicit.

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