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

Annotations already establish read-only, idempotent, and non-destructive behavior, but the description adds substantial new context: no access prerequisite, no probe trigger, separation of observation scopes, and a warning about over-interpreting results. These disclosures go beyond the structured hints and meaningfully shape how an agent should use and interpret the tool. There is no contradiction with the 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?

Five short sentences each carry distinct information: purpose, access requirements, observation scoping, interpretive caveat, and side-effect behavior. The primary action is front-loaded and no sentence is redundant with the schema or annotations.

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 parameterless read tool with no output schema, the description covers what data is returned, the access model, the separation of observation scopes, and the limits of interpretation. Nothing an agent needs to decide whether to call it or to interpret its result 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?

The schema declares zero parameters and schema description coverage is 100%, so there is no parameter meaning for the description to add. Per the zero-parameter baseline, the description is not penalized and appropriately spends its words on behavioral context instead.

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 first sentence names the action 'Read' and a precise resource ('versioned synthetic probe outcomes') with specific data fields, making the tool's function immediately identifiable. The closing 'This tool does not trigger a probe' further disambiguates it from probe-invoking tools.

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 usage context: no ACTE or registration is required, internal/local/external observations are separated, and the tool does not trigger a probe. It also includes an explicit interpretive exclusion: 'A narrow test is not a general safety certification.' It stops short of naming sibling alternatives for comparison, so it does not reach the top score.

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