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

Annotations already declare read-only, idempotent, and non-destructive behavior. The description adds valuable beyond-annotation context: it guarantees no ciphertext is returned, cites GDPR compliance, and states a per-call cost. These are behavioral traits an agent would otherwise not know.

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?

Three concise sentences, each earning its place: the main action and scope, the critical safety guarantee, and the compliance/cost operational details. All essential information is front-loaded in the first sentence, with no filler or repetition of schema content.

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 a full output schema and 100% parameter documentation, the description needs to cover only behavioral and operational context, which it does well (sensitivity, compliance, cost). It could go slightly further by explicitly naming a sibling alternative, but that is a usage-guidance refinement rather than a missing piece.

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%, so the schema fully documents all four required parameters including entity_id, tool_name, owner_wallet, and wallet_signature. The description does not add parameter-level meaning beyond what the schema already provides, so the baseline of 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?

The description opens with the specific verb 'Retrieve' and the resource 'non-sensitive metadata on prior tool invocations for an entity', followed by concrete fields (count, timestamps, last hash). This clearly distinguishes it from memory.read/query, which likely return content, and the phrase 'Never returns ciphertext' reinforces what the tool is and is not.

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 provides clear context: it is a metadata-only retrieval tool, safe in terms of sensitivity, and with a stated cost. It does not explicitly name when to use it over siblings like memory.read, but the 'never returns ciphertext' statement strongly implies it is for non-sensitive metadata access, giving an implicit exclusion.

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