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

Annotations already declare readOnlyHint=true, so the safe-read nature is covered. The description adds that the memo is for a memoless transaction and that it is 'registered', but it does not explain the non-idempotent hint or what happens when no memo exists, so it only partially extends the structured behavioral data.

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 short and front-loads the return behavior, but the second sentence largely restates the first ('look up the registered memo for a memoless transaction' vs 'Returns the memoless transaction memo'). One sentence would have sufficed, so there is some redundancy.

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 one-parameter read tool with annotations covering the safety profile and no output schema, the description states what is returned and for which kind of transaction. It omits error/not-found behavior, but otherwise gives enough to invoke the tool correctly.

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 single hash parameter is already documented as 'The transaction hash'. The description refers to it as a 'reference hash', which is a minor terminology variation but adds no format, constraint, or validation detail beyond the schema. 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?

States a specific verb ('Returns') and resource ('memoless transaction memo') and scopes it to a given reference hash. It is clear what the tool does, but it does not explicitly differentiate itself from siblings like get_reference_memo or check_reference_memo.

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 second sentence gives a usage context ('Use this to look up the registered memo for a memoless transaction'), which implies when to use it. However, it offers no exclusions or explicit alternatives among the many sibling tools, leaving the agent to infer the boundary.

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