history

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It reveals that the tool returns historical information (first/last seen, count) and implies a read-only query, but it does not explicitly state read-only status, error handling, or any side effects. For a simple query tool, this is acceptable but not exhaustive.

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 zero filler. The first sentence directly states the query, and the second explains the use case. It is front-loaded with the core purpose and efficiently conveys essential information.

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?

Given the tool's simplicity (one required parameter, output schema exists) and the description's coverage of purpose and usage, it is largely complete. It could explicitly mention that the tool is read-only, but that omission is minor given the lack of annotations and the straightforward nature of the operation.

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 defines 'fingerprint' as a plain string with no description (0% coverage). The tool description adds meaning by referring to it as a 'failure fingerprint' and using it in context, clarifying that it identifies a specific failure pattern. This compensates for the lack of schema documentation.

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 explicitly states what the tool returns (first/last seen, count) and identifies the resource (failure fingerprint). It also gives a specific use case—distinguishing new regressions from long-standing breakage—which clearly differentiates it from siblings like verify or explain_failure.

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 a clear when-to-use: when you need to know if a fingerprint is unknown (possible regression) or has been seen across runs/commits (long-standing breakage). It gives a concrete scenario but does not explicitly name alternatives or state when not to use the tool, so it falls just short of a 5.

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